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CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 1 R.M.K COLLEGE OF ENGINEERING AND TECHNOLOGY RSM NAGAR, PUDUVOYAL-601206 DEPARTMENT OF MECHANICAL ENGINEERING CE6451 – FLUID MECHANICS & MACHINERY III SEM Regulation 2013

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CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 1

R.M.K COLLEGE OF ENGINEERING

AND TECHNOLOGY RSM NAGAR, PUDUVOYAL-601206

DEPARTMENT OF MECHANICAL ENGINEERING

CE6451 – FLUID MECHANICS & MACHINERY

III SEM

Regulation 2013

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 2

UNIT - I - FLUID PROPERTIES AND FLOW CHARACTERISTICS Part – A 1.1)What is a fluid? How are fluids classified? 1.2)Define fluid. Give examples. [DEC 10] 1.3)How fluids are classified? [DEC 08, JUN 12] 1.4)Distinguish between solid and fluid. [JUN 06] 1.5)Differentiate between solids and liquids. [JUN 07] 1.6)Discuss the importance of ideal fluid. [MAY 11] 1.7)W h a t is a real fluid? [MAY 03] 1.8)Define Newtonian and Non – Newtonian fluids. [DEC 08] 1.9)What are Non – Newtonian fluids? Give example. [DEC 09] 1.10)Differentiate between Newtonian and Non – Newtonian fluids. [DEC 07] 1.11)What is the difference between an ideal and a real fluid? 1.12)Differentiate between liquids and gases. 1.13)Define Pascal’s law. [DEC – 2005, 2008] 1.14)Define the term density. 1.15)Define mass density and weight density. [DEC 07] 1.16)Distinguish between the mass density and weight density.[JUN 09] 1.17)Define the term specific volume and express its units.[MAY 11] 1.18)Define specific weight. 1.19)Define specific weight and density. [JUN 12] 1.20)Define density and specific gravity of a fluid. [DEC 12] 1.21)Define the term specific gravity. 1.22)What is specific weight and specific gravity of a fluid? [MAY 10] 1.23)What is specific gravity? How is it related to density? [MAY 08] 1.24)What do you mean by the term viscosity? 1.25)What is viscosity? What is the cause of it in liquids and in gases?[DEC 05] 1.26)Define Viscosity and give its unit. [DEC 03] 1.27)Define Newton’s law of viscosity. [DEC 12] 1.28)State the Newton's law of viscosity.[MAY, DEC 05, JUN 07] 1.29)Define Newton’s law of viscosity and write the relationship between shear stress

and velocity gradient?[DEC 06] 1.30)What is viscosity and give its units? [MAY 11] 1.31)Define coefficient of viscosity. [MAY 05] 1.32)Define coefficient of volume of expansion. [DEC 12] 1.33)Define relative or specific viscosity. [JUN 13] 1.34)Define kinematic viscosity. [DEC 09] 1.35)Define kinematic and dynamic viscosity. [JUN 06] 1.36)Mention the significance of kinematic viscosity. [DEC 11] 1.37)What is dynamic viscosity? What are its units? 1.38)Define dynamic viscosity. [DEC 08, JUN 12] 1.39)Define the terms kinematic viscosity and give its dimensions.[JUN 09] 1.40)What is kinematic viscosity? State its units? [JUN 14] 1.41)Differentiate between kinematic viscosity of liquids and gases with respect to

pressure [DEC 13] 1.42)Write the units and dimensions for kinematic and dynamic viscosity.[DEC 05] 1.43)What are the units and dimensions for kinematic and dynamic viscosity of a

fluid? [DEC 06, 12]

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 3

1.44)Differentiate between kinematic and dynamic viscosity.[JUN 07, DEC – 08, 11] 1.45)How does the dynamic viscosity of liquids and gases vary with

temperature?[DEC 07, MAY 08] 1.46)What are the variations of viscosity with temperature for fluids? [DEC 09] 1.47)What is the effect of temperature on viscosity of water and that of air? 1.48)Why is it necessary in winter to use lighter oil for automobiles than in summer?

To what property does the term lighter refer? [DEC 10] 1.49)Define the term pressure. What are its units? [DEC 05] 1.50)Give the dimensions of the following physical quantities[MAY 03]

a) Pressure b) surface tension c) Dynamic viscosity d) kinematic

1.51)Define eddy viscosity. How it differs from molecular viscosity?[DEC 10] 1.52)Define surface tension. [JUN 06] 1.53)Define surface tension and expression its unit. [MAY 11] 1.54)Define capillarity. [DEC 05, JUN 06] 1.55)What is the difference between cohesion and adhesion? 1.56)Define the term vapour pressure. 1.57)What is meant by vapour pressure of a fluid? [MAY 10] 1.58)What are the types of pressure measuring devices? 1.59)What do you understand by terms: (i) Isothermal process ii) adiabatic process 1.60)What do you mean by capillarity? [DEC 09] 1.61)Explain the phenomenon of capillarity. 1.62)What is compressibility of fluid? 1.63)Define compressibility of the fluid.[DEC – 2008, JUN 09] 1.64)Define compressibility and viscosity of a fluid. [MAY 05] 1.65)Define coefficient of compressibility. What is its value for ideal gases? [DEC 10] 1.66)List the components of total head in a steady, incompressible irrotational

flow.[DEC 09] 1.67)Define the bulk modulus of fluid. [DEC 08] 1.68)Define - compressibility and bulk modulus. [DEC – 2011] 1.69)Write short notes on thixotropic fluid. 1.70)What is Thixotropic fluid? [DEC 03] 1.71)One poise’s equal toPa.s. 1.72)Give the types of fluid flow. 1.73)Define steady flow and give an example. 1.74)Define unsteady flow and give an example. 1.75)Differentiate between the steady and unsteady flow. [JUN 06] 1.76)When the flow regarded as unsteady? Give an example for unsteady flow.

MAY03 1.77)Define uniform flow and give an example. 1.78)Define non uniform flow and give an example. 1.79)Differentiate between steady flow and uniform flow.[DEC 07] 1.80)Define laminar and turbulent flow and give an example. 1.81)Differentiate between laminar and turbulent flow.[DEC – 2005, 2008] 1.82)Distinguish between Laminar and Turbulent flow. [MAY 10] [DEC 06] 1.83)State the criteria for laminar flow. [DEC 08] 1.84)State the characteristics of laminar flow. [MAY 10]

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 4

1.85)What are the characteristics of laminar flow? [JUN 14] 1.86)Mention the general characteristics of laminar flow. [JUN 13] 1.87)Define compressible and incompressible flow and give an example. 1.88)Define rotational and irrotational flow and give an example. 1.89)Distinguish between rotation and circularity in fluid flow. [MAY 05] 1.90)Define stream line. What do stream lines indicate? [DEC 07] 1.91)Define streamline and path line in fluid flow. [DEC 05] 1.92)What is stream line and path line in fluid flow? [MAY 10] 1.93)What is a streamline? [DEC 10] 1.94)Define streak line. [MAY 08] 1.95)Define stream function. [MAY – 2010, JUN 12] 1.96)Define control volume. 1.97)What is meant by continuum? [DEC 08] 1.98)Define continuity equation. 1.99)Write down the equation of continuity. [DEC –2008, 2009, 2012] 1.100)State the continuity equation in one dimensional form?[JUN12] 1.101)State the general continuity equation for a 3 - D incompressible fluid flow. [JUN

07, DEC 12] 1.102)State the continuity equation for the case of a general 3-D flow. [DEC 07] 1.103)State the equation of continuity in 3dimensional incompressible flow. [DEC 05] 1.104)State the assumptions made in deriving continuity equation[DEC 11] 1.105)Define Euler's equation of motion. 1.106)Write the Euler's equation. [MAY 11] 1.107)What is Euler’s equation of motion? [DEC 08] 1.108)Define Bernoulli's equation. 1.109)Write the Bernoulli’s equation in terms of head. Explain each term. [DEC07] 1.110)What are the basic assumptions made is deriving Bernoulli’s theorem?[DEC

05,12] 1.111)List the assumptions which are made while deriving Bernoulli’s

equation.[JUN12] 1.112)State at least two assumptions of Bernoulli’s equation. [JUN 09] 1.113)What are the three major assumptions made in the derivation of the Bernoulli’s

equation? [MAY 08] 1.114)State Bernoulli’s theorem as applicable to fluid flow. [DEC 03] 1.115)Give the assumptions made in deriving Bernoulli’s equation.[DEC 12] 1.116)What are the applications of Bernoulli’s theorem?[MAY 10] 1.117)Give the application of Bernoulli’s equation. 1.118)List the types of flow measuring devices fitted in a pipe flow, which uses the

principle of Bernoulli’s equation. [JUN 12] 1.119)Mention the uses of manometer.[DEC 09] 1.120)State the use of venturimeter.[JUN 06] 1.121)Define momentum principle. 1.122)Define impulse momentum equation. 1.123)Write the impulse momentum equation. [JUN 07] 1.124)What do you understand by impulse momentum equation [JUN 13] 1.125)State the momentum equation. When can it applied.[JUN 09] 1.126)State the usefulness of momentum equation as applicable to fluid flow

phenomenon.[JUN – 2007, DEC 12]

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 5

1.127)Define discharge (or) rate of flow. 1.128)Discuss the momentum flux. [MAY 11] 1.129)Find continuity equation, when the fluid is incompressible and Densities are

equal 1.130)What is the moment of momentum equation? [JUN 14] 1.131)Explain classification of fluids based on viscosity. 1.132)State and prove Euler's equation of motion. Obtain Bernoulli's equation from

Euler's equation. 1.133)State and prove Bernoulli's equation. What are the limitations of The Bernoulli's

equation? 1.134)State the momentum equation. How will you apply momentum equation for

determining the force exerted by a flowing liquid on a pipe bend? 1.135)Give the equation of continuity. Obtain an expression for continuity equation for

a three - dimensional flow. 1.136)Calculate the density of one litre petrol of specific gravity 0.7?[MAY 11] 1.137)A soap bubble is formed when the inside pressure is 5 N/m2 above the

atmospheric pressure. If surface tension in the soap bubble is 0.0125 N/m, find the diameter of the bubble formed.[MAY 10]

1.138)The converging pipe with inlet and outlet diameters of 200 mm and 150 mm carries the oil whose specific gravity is 0.8.The velocity of oil at the entry is 2.5 m/s, find the velocity at the exit of the pipe and oil flow rate in kg/sec. [MAY 10]

1.139)Find the height through which the water rises by the capillary action in a 2mm bore if the surface tension at the prevailing temperature is0.075 g/cm.[MAY 03]

1.140)Find the height of a mountain where the atmospheric pressure is 730mm of Hg at normal conditions.[DEC09]

1.141)Suppose the small air bubbles in a glass of tap water MAY be on the order of 50μ m in diameter. What is the pressure inside these bubbles? [DEC 10]

1.142)An open tank contains water up to depth of 2.85m and above it an oil of specific gravity 0.92 for the depth of 2.1m. Calculate the pressures at the interface of two liquids and at the bottom of the tank. [MAY 11]

1.143)Two horizontal plates are placed 12.5mm apart, the space between them is being filled with oil of viscosity 14 poise. Calculate the shear stress in the oil if the upper plate is moved with the velocity of 2.5m/s. Define specific weight.[JUN 12]

1.144)Calculate the height of capillary rise for water in a glass tube of Diameter 1mm.[JUN 12]

PART – B 1.145)What are the various classification of fluids? Discuss [DEC 12] 1.146)State and prove Pascal's law. [JUN, DEC 07] 1.147)What is Hydrostatic law? Derive an expression to show the same.[DEC 09] 1.148)Explain the properties of hydraulic fluid. [DEC 09] 1.149)Discuss the equation of continuity. Obtain an expression for continuity equation in three dimensional forms.[MAY 11] 1.150)Explain in detail the Newton's law of viscosity. Briefly classify the fluids based on the density and viscosity. Give the limitations of applicability of Newton's law of viscosity.[MAY 11] 1.151)State the effect of temperature and pressure on viscosity. [JUN 09] 1.152)Explain the term specific gravity, density, compressibility and vapour pressure.

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 6

[JUN 09] 1.153)Explain the terms Specific weight, Density, Absolute pressure and Gauge pressure.[MAY 11] 1.154)Define Surface tension and also compressibility of a fluid?[DEC 06] 1.155)Explain the phenomenon surface tension and capillarity. [MAY 11] 1.156)Derive an expression for the capillary rise of a liquid having surface tension σ and contact angle θ between two vertical parallel plates at a distance W apart. If the plates are of glass, what will be the capillary rise of water? Assume σ = 0.773N / m, θ= 0° Take W=l mm.[JUN 14] 1.157)What is compressibility of fluids? Give the relationship between compressibility and bulk modulus[DEC09] 1.158)Prove that the relationship between surface tension and pressure inside the droplet of liquid in excess of outside pressure is given by P = 4σ/d.[MAY–10,11,DEC08] 1.159)Explain the following 1. Capillarity 2. Surface tension 3. Compressibility 4. Kinematic viscosity [JUN12] 1.160)Derive the energy equation and state the assumptions made while deriving the equation.[DEC 10] 1.161)Derive Euler's equation of motion.[JUN 14] 1.162)Derive from the first principles, the Euler’s equation of motion for a steady flow along a stream line. Hence derive Bernoulli’ equation. State the various assumptions involved in the above derivation.[JUN 09] 1.163)Derive from basic principle the Euler’s equation of motion in 2D flow in X-Y coordinate system and reduce the equation to get Bernoulli’s equation for unidirectional stream lined flow.[MAY 05] 1.164)State Euler’s equation of motion, in the differential form. Derive Bernoulli’s equation from the above for the cases of an ideal fluid flow.[JUN 07, DEC 12] 1.165)State the law of conservation of man and derive the equation of continuity in Cartesian coordinates for an incompressible fluid. Would it alter if the flow were unsteady, highly viscous and compressible?[MAY 11] 1.166)Derive the equation of continuity for one dimensional flow.[DEC 08, MAY10] 1.167)Derive the continuity equation for 3 dimensional flow in Cartesian coordinates.[JUN 06] 1.168)Derive the general form of continuity equation in Cartesian coordinates. [DEC 12] 1.169)Derive the continuity equation of differential form. Discuss weathers equation is valid for a steady flow or unsteady flow, viscous or in viscid flow, compressible or incompressible flow. [MAY 03] 1.170)Derive continuity equation from basic principles.[DEC 09] 1.171)Derive Bernoulli’s equation along with assumptions made.[JUN 07] 1.172)State Bernoulli’s theorem for steady flow of an in compressible fluid. [DEC – 04, 05, MAY – 10, JUN 13] 1.173)State Bernoulli’s theorem for steady flow of an in compressible fluid. 1.174)Derive an expression for Bernoulli equation and state the assumptions made.[JUN 09] 1.175)State the assumptions in the derivation of Bernoulli’s equation.[JUN, DEC 07] 1.176)Derive an expression for Bernoulli’s equation for a fluid flow.[DEC – 04, 05, MAY 10] 1.177)Derive Bernoulli’s equation from the first principles? State the assumptions made while deriving Bernoulli’s equation.[JUN 12]

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 7

1.178)Derive from basic principle the Euler’s equation of motion in Cartesian co -ordinates system and deduce the equation to Bernoulli’s theorem steady irrotational flow.[MAY 04] 1.179)Derive the Euler’s equation of motion and deduce the expression to Bernoulli’s equation.[DEC 12] 1.180)Develop the Euler equation of motion and then derive the one dimensional form of Bernoulli’s equation.[DEC 11] 1.181)Show that for a perfect gas the bulk modulus of elasticity equals its pressure for 1. An isothermal process 2. γ times the pressure for an isentropic process[MAY 03] 1.182)State and derive impulse momentum equation. [MAY 05] 1.183)Derive momentum equation for a steady flow. [JUN 12] 1.184)Derive the linear momentum equation using the control volume approach and determine the force exerted by the fluid flowing through a pipe bend. [DEC 11] 1.185)With a neat sketch, explain briefly an orifice meter and obtain an expression for the discharge through it.[DEC 12] 1.186)Draw the sectional view of Pitot’s tube and write its concept to measure velocity of fluid flow? [MAY 05]

PROBLEMS 1.187)A soap bubble is 60mm in diameter. If the surface tension of the soap film is 0.012 N/m. Find the excess pressure inside the bubble and also derive the expression used in this problem.[DEC 09] 1.188)A spherical water droplet of 5 mm in diameter splits up in the air into 16 smaller droplets of equal size. Find the work involved in splitting up the droplet. The surface tension of water MAY be assumed as 0.072 N/m [DEC 12] 1.189)A liquid weighs 7.25N per litre. Calculate the specific weight, density and specific gravity of the liquid. 1.190)One litre of crude oil weighs 9.6N. Calculate its specific weight, density and specific gravity.[DEC 08] 1.191)Determine the viscosity of a liquid having a kinematic viscosity 6 stokes and specific gravity 1.9.[DEC 08, MAY 10] 1.192)Determine the mass density; specific volume and specific weight of liquid whose specific gravity 0.85.[MAY 10] 1.193)If the volume of a balloon is to reach a sphere of 8m diameter at an altitude where the pressure is 0.2 bar and temperature -40°C. Determine the mass hydrogen to be charged into the balloon and volume and diameter at ground level. Where the pressure is 1bar and temperature is 25°C. [DEC 09] 1.194)A pipe of 30 cm diameter carrying 0.25 m3/s water. The pipe is bent by 135° from the horizontal anti-clockwise. The pressure of water flowing through the pipe is 400 kN. Find the magnitude and direction of the resultant force on the bend. [DEC 11] 1.195)A liquid has a specific gravity of 0.72. Find its density and specific weight.

Find also the weight per litre of the liquid. 1.196)A 1.9mm diameter tube is inserted into an unknown liquid whose density is 960kg/m3, and it is observed that the liquid raise 5mm in the tube, making a contact angle of 15°. Determine the surface tension of the liquid.[MAY 08] 1.197)A 0.3m diameter pipe carrying oil at 1.5m/s velocity suddenly expands to 0.6m diameter pipe. Determine the discharge and velocity in 0.6m diameter pipe.[JUN12] 1.198)Explain surface tension. Water at 20°C (σ = 0.0.73N/m, γ = 9.8kN/m3 and angle of contact = 0°) rises through a tube due to capillary action. Find the tube diameter requires, if the capillary rise is less than 1mm.[DEC 10]

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 8

1.199)A Newtonian fluid is filled in the clearance between a shaft and a concentric sleeve. The sleeve attains a speed of 50cm/s, when a force of 40N is applied to the sleeve parallel to the shaft. Determine the speed of the shaft, if a force of 200N is applied.[DEC 06] 1.200)An oil film thickness 10mm is used for lubrication between the square parallel plate of size 0.9 m * 0.9 m, in which the upper plate moves at 2m/s requires a force of 100 N to maintain this speed. Determine the

Dynamic viscosity of the oil in poise and Kinematic viscosity of the oil in stokes. The specific gravity of the oil is 0.95.[DEC – 2003]

1.201)The space between two square flat parallel plates is filled with oil. Each side of the plate is 60cm. The thickness of the oil film is 12.5mm. The upper plate, which moves at 2.5 meter per sec, requires a force of 98.1N to maintain the speed. Determine the 1. Dynamic viscosity of the oil in poise and 2. Kinematic viscosity of the oil in stokes.

3. The specific gravity of the oil is 0.95. [DEC 12] 1.202)What is the bulk modulus of elasticity of a liquid which is compressed in a cylinder from a volume of 0.0125m3 at 80N/cm2 pressure to a volume of 0.0124m3 at pressure 150N/cm2 [DEC 04] 1.203)Determine the bulk modulus of elasticity of elasticity of a liquid, if the pressure of the liquid is increased from 7MN/m2 to 13MN/m2, the volume of liquid Decreases by 0.15%.[JUN 09] 1.204)The measuring instruments fitted inside an airplane indicate the pressure 1.032 *105Pa, temperature T0 = 288 K and density ρ0 = 1.285 kg/m3 at takeoff. If a standard temperature lapse rate of 0.0065° K/m is assumed, at what elevation is the plane when a pressure of 0.53*105 recorded? Neglect the variations of acceleration due gravity with the altitude and take airport elevation as 600m. A person must breathe a constant mass rate of air to maintain his metabolic process. If he inhales 20 times per minute at the airport level of 600m, what would you except his breathing rate at the calculated altitude of the plane? [JUN 09] 1.205)The space between two square parallel plates is filled with oil. Each side of the plate is 75 cm. The thickness of oil film is 10 mm. The upper plate which moves at 3 m/s requires a force of 100 N to maintain the speed. Determine the

Dynamic viscosity of the oil Kinematic viscosity of the oil, if the specific gravity of the oil is 0.9.

1.206)A rectangular plate of size 25cm* 50cm and weighing at 245.3 N slides down at 30° inclined surface with uniform velocity of 2m/s. If the uniform 2mm gap between the plates is inclined surface filled with oil. Determine the viscosity of the oil. [MAY – 2004, DEC 12] 1.207)A space between two parallel plates 5mm apart, is filled with crude oil of specific gravity 0.9. A force of 2N is require to drag the upper plate at a constant velocity of 0.8m/s. the lower plate is stationary. The area of upper plate is 0.09m2. Determine the dynamic viscosity in poise and kinematic viscosity of oil in strokes. [JUN 09]

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 9

1.208)The space between two large flat and parallel walls 25mm apart is filled with liquid of absolute viscosity 0.7 Pa.sec. Within this space a thin flat plate 250mm * 250 mm is towed at a velocity of 150mm/s at a distance of 6mm from one wall, the plate and its movement being parallel to the walls. Assuming linear variations of velocity between the plates and the walls, determine the force exerted by the liquid on the plate.[JUN 12] 1.209)A jet issuing at a velocity of 25 m/s is directed at 35° to the horizontal. Calculate the height cleared by the jet at 28 m from the discharge location? Also determine the maximum height the jet will clear and the corresponding horizontal location. [DEC 11] 1.210)A flat plate of area 0.125m2 is pulled at 0.25 m/sec with respect to another parallel plate 1mm distant from it, the space between the plates containing water of viscosity 0.001Ns/ m2. Find the force necessary to maintain this velocity. Find also the power required. 1.211)Lateral stability of a long shaft 150 mm in diameter is obtained by means of a 250 mm stationary bearing having an internal diameter of 150.25 mm. If the space between bearing and shaft is filled with a lubricant having a viscosity 0.245 N s/m2, what power will be required to overcome the viscous resistance when the shaft is rotated at a constant rate of 180 rpm? [DEC 10] 1.212)Find the kinematic viscosity of water whose specific gravity is 0.95 and Viscosity is 0.0011Ns/m2. 1.213)The dynamic viscosity of oil, used for lubrication between a shaft and sleeve is6poise. The shaft is of diameter 0.4m and rotates at 190 rpm. Calculate the power lost in the bearing for a sleeve length of 90mm. The thickness of the oil film is 1.5mm.[DEC 07, JUN 12] 1.214)A 200 mm diameter shaft slides through a sleeve, 200.5 mm in diameter and 400 mm long, at a velocity of 30 cm/s. The viscosity of the oil filling the annular space is m = 0.1125 NS/ m2. Find resistance to the motion. [A.U. DEC 08] 1.215)A 0.5m shaft rotates in a sleeve under lubrication with viscosity 5 Poise at 200rpm. Calculate the power lost for a length of 100mm if the thickness of the oil is 1mm. [DEC 09] 1.216)A 15 cm diameter vertical cylinder rotates concentrically inside another cylinder of diameter 15.10 cm. Both cylinders are 25 cm high. The space between the cylinders is filled with a liquid whose viscosity is unknown. If a torque of 12.0 Nm is required to rotate the inner cylinder at 100 rpm, determine the viscosity of the fluid. [JUN 13] 1.217)A400 mm diameter shaft is rotating at 200 r.p.m. in a bearing of length 120 mm. If the thickness of film is 1.5 mm and the dynamic viscosity of the oil is 0.7 N.s/m2, determine (i) Torque required to overcome friction in bearing (ii) Power utilized to overcoming viscous friction. Assume linear velocity profile.[JUN 14] 1.218)Calculate the gauge pressure and absolute pressure within (i) a droplet of water 0.4cm in diameter (ii) a jet of water 0.4cm in diameter. Assume the surface tension of water as 0.03N/m and the atmospheric pressure as 101.3kN/m2. 1.219)What do you mean by surface tension? If the pressure difference between the inside and outside of air bubble of diameter, 0.01 mm is 29.2kPa, what will be the surface tension at air water interface? Derive an expression for the surface tension in

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 10

the air bubble and from it, deduce the result for the given conditions. [DEC 05] 1.220)At the depth of 2km in ocean the pressure is 82401kN/m2. Assume the specific gravity at the surface as 10055 N/m3 and the average bulk modulus of elasticity is 2.354 * 109 N/m2 for the pressure range. Determine the change in specific volume between the surface and 2km depth and also determine the specific weight at the depth?[MAY – 04, DEC 12] 1.221)At the depth of 8km from the surface of the ocean, the pressure is stated to be 82MN/m2. Determine the mass density, weight density and specific volume of water at this depth. Take density at the surface ρ = 1025kg/m3 and bulk modulus K = 2350MPa for indicated pressure range.[JUN 09] 1.222)Eight kilometers below the surface of ocean pressure is 81.75MPa. Determine the density of sea water at this depth if the density at the surface is 1025 kg/m3 and the average bulk modulus of elasticity is 2.34GPa. [JUN 12]

1.223)A liquid is compressed in a cylinder having a volume of 0.012 m3 at a pressure of 690 N/cm2. What should be the new pressure in order to make its volume 0.0119 m3? Assume bulk modulus of elasticity (K) for the liquid = 6.9 x 104 N/cm2. [JUN 13] 1.224)Calculate the capillary rise in glass tube of 3 mm diameter when immersed in mercury; take the surface tension and the angle of contact of mercury as 0.52 N/m and 130° respectively. Also determine the minimum size of the glass tube, if it is immersed in water, given that the surface tension of water is 0.0725 N/m and capillary rise in the tube is not to exceed 0.5mm.[DEC 03] 1.225)The capillary rise in a glass tube is not to exceed 0.2mm of water. Determine its minimum size, given that the surface tension for water in contact with air = 0.0725N/m.[DEC07, JUN 12] 1.226)Calculate the capillary effect in millimeters in a glass tube of 4mm diameter when immersed in (i) water and (ii) mercury. The temperature of the liquid is 20°C and the values of surface tension of water and mercury at 20°C in contact with air are 0.0735N/m and 0.51N/m respectively. The contact angle for water u=0° and for mercury u=130°.Take specific weight of water at 20°C as equal to 9780 N/m3.[DEC 07] 1.227)Derive an expression for the capillary rise at a liquid in a capillary tube of radius r having surface tension σ and contact angle θ. If the plates are of glass, what will be the capillary rise of water having σ = 0.073 N/m, θ = 0°? Take r = 1mm. [DEC 11] 1.228)A pipe containing water at 180kN/m2 pressure is connected to differential gauge to another pipe 1.6m lower than the first pipe and containing water at high pressure. If the difference in height of 2 mercury columns of the gauge is equal to 90mm, what is the pressure in the lower pipe? [DEC 08] 1.229)Determine the minimum size of glass tubing that can be used to measure water level. If the capillary rise in the tube is not exceed 2.5mm. Assume surface tension of water in contact with air as 0.0746 N/m. [DEC – 2004, 2012] 1.230)Calculate the capillary effect in millimeters in a glass tube of 4 mm diameter, when immersed in (i) water and (ii) mercury. The temperature of the liquid is 20°C and the values of surface tension of water and mercury at 20°C in contact with air are

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 11

0.0735 N/m and 0.51 N/m respectively. The contact angle for water u = 0 and for mercury u = 130°. Take specific weight of water at 20°C as equal to 9790N/ m3. [DEC – 05, 07] 1.231)A Capillary tube having inside diameter 6 mm is dipped in CCl4at 20o C. Find the rise of CCl4 in the tube if surface tension is 2.67 N/m and Specific gravity is1.594 and contact angle u is 60° and specific weight of water at 20° C is 9981 N/m3.[DEC 08] 1.232)Two pipes A & B are connected to a U – tube manometer containing mercury of density 13,600kg/m3. Pipe A carries a liquid of density 1250kg/m3 and a liquid of density 800kg/m3 flows through a pipe B, The center of pipe A is 80mm above the pipe B. The difference of mercury level manometer is 200mm and the mercury surface on pipe a side is 100mm below the center. Find the difference of pressure between the two connected points of the pipes. [DEC 10] 1.233)A crude oil of viscosity 0.9 poise and relative density 0.9 is flowing through a horizontal circular pipe of diameter 120 mm and length 12 m. Calculate the difference of pressure at the two ends of the pipe, if 785 N of the oils collected in a tank in 25 seconds. [JUN 14] 1.234)A simple U tube manometer containing mercury is connected to a pipe in which a fluid of specific gravity 0.8 and having vacuum pressure is flowing. The other end of the manometer is open to atmosphere. Find the vacuum pressure in the pipe, if the difference of mercury level in the two limbs is 40cm and the height of the fluid in the left from the center pipe is 15cm below. Draw the sketch for the above problem. [MAY 11, JUN 12] 1.235)A U-tube is made of two capillaries of diameter 1.0 mm and 1.5 mm respectively. The tube is kept vertically and partially filled with water of surface tension 0.0736 N/m and zero contact angles. Calculate the difference in the levels of the menisci caused by the capillary.[DEC 10] 1.236)Define the terms gauge pressure and absolute pressure. A U tube containing mercury has its right limb open to atmosphere. The left limb is full of water and is connected to a pipe containing water under pressure, the Centre of which is in the level with the free surface of mercury. If the difference in the levels of mercury in the limbs id 5.1cm, calculate the water pressure in the pipe. [DEC 12] 1.237)The barometric pressure at sea level is 760 mm of mercury while that on a mountain top is735 mm. If the density of air is assumed constant at 1.2 kg/m3, what is the elevation of the mountain top? [DEC 07] 1.238)The barometric pressure at the top and bottom of a mountain are 734mm and 760mm of mercury respectively. Assuming that the average density of air = 1.15kg/m3, calculate the height of the mountain. [DEC 09] 1.239)The maximum blood pressure in the upper arm of a healthy person is about 120 mmHg. If a vertical tube open to the atmosphere is connected to the vein in the arm of the person, determine how high the blood will rise in the tube.Take the density of the blood to be 1050 kg/ m3.[MAY 08] 1.240)When a pressure of 20.7 MN/m2 is applied to 100 L of a liquid, its volume decreases by one L. Find bulk modulus of the liquid and identify this liquid. [DEC 07]

1.241)Determine the minimum size of the glass tubing that can be used to measure

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 12

water level. If the capillary rise in the tube is not to exceed 2.5mm. Assume surface tension of water in contact with air as 0.0746 N/m[MAY 04] 1.242)A cylinder of 0.6m3 in volume contains air at 50oC and 0.3N/mm2 absolute pressure. The air is compressed to 0.3m3. Find the (i) pressure inside the cylinder assuming isothermal process and (ii) pressure and temperature assuming adiabatic process. Take k = 1.4. 1.243)A 30cm dia pipe, conveying water branches into two pipes of diameters 20cm and 15cm respectively. If the average velocity in the 30cm diameter pipe is 2.5m/sec, find the discharge in this pipe. Also determine the velocity in the 15cm diameter pipe if the average velocity in the 20cm diameter pipe is 2m/sec. [DEC 08,MAY 10]

1.244)Water flows through a pipe AB 1.2m diameter at 3m/second then passes through a pipe BC 1.5m diameter. At C, the pipe branches. Branch CD is 0.8m in diameter and carries one - third of the flow in AB. The flow velocity in branch CE is 2.5m/sec. Find the volume rate of flow in AB, the velocity in BC, the velocity in CD and the diameter of CE. 1.245)Water is flowing through a pipe having diameters 20cm and 10cm at sections 1 and 2 respectively. The rate of flow, through the pipe is 35litre/sec. The section 1 is 6m above datum and section 2 is 4m above datum. If the pressure at section 1 is 39.24N/cm2, find the intensity of pressure at section 2. [DEC 08] 1.246)A pipe of diameter 400mm carries water at a velocity of 25m/sec. The pressures at the points A and B are given as 29.43N/cm2 and 22.563 N/cm2 respectively, while the datum head at A and B are 28m and 30m. Find the loss of head between A and B. 1.247)A drainage pipe is tapered in a section running with full of water.The pipe diameters at the inlet and exit are 1000 mm and 50 mm respectively. The water surface is 2 m above the center of the inlet and exit is 3 m above the free surface of the water. The pressure at the exit is250 mm of Hg vacuum. The friction loss between the inlet and exit of the pipe is 1/10 of the velocity head at the exit. Determine the discharge through the pipe.[MAY 10] 1.248)A pipeline 60 cm in diameter bifurcates at a Y- junction into two branches 40 cm and 30 cm in diameter. If the rate of flow in the main pipe is 1.5 m3/s, and the mean velocity of flow in the 30 cm pipe is 7.5 m/s, determine the rate of flow in the 40 cm pipe.[DEC 10] 1.249)A pipeline of 175 mm diameter branches into two pipes which delivers the water at atmospheric pressure. The diameter of the branch 1 which is at 35° counter-clockwise to the pipe axis is 75mm. and the velocity at outlet is 15 m/s. The branch 2 is at 15° with the pipe center line in the clockwise direction has a diameter of 100 mm. The outlet velocity is 15 m/s. The pipes lie in a horizontal plane. Determine the magnitude and direction of the forces on the pipes. [DEC 11] 1.250)A pipeline conveys 10 lit/s of water from an overhead tank to a building. The pipe is 2km long and 15cm diameter, the friction factor is 0.03. It is planned to increase the discharge by 30% by installing another pipeline in parallel with this over half the length. Find the suitable diameter of pipe to be installed. Is there any upper limit on discharge augmentation by this arrangement?[DEC 12] 1.251)The water is flowing through a taper pipe of length 100 m having diameters 600 mm at the upper end and 300 mm at the lower end, at the rate of 50 litres/s. The pipe has a slope of 1 in 30. Find the pressure at the lower end if the pressure at the

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 13

higher level is 19.62 N/cm2.[JUN 13] 1.252)A 45° reducing bend is connected in a pipe line, the diameters at the inlet and outlet of the bend being 600mm and 300mm respectively. Find the force exerted by water on the bend if the intensity of pressure at the inlet to the bend is 8.829N/cm2 and rate of flow of water is600 litre / sec. 1.253)Gasoline (specific gravity = 0.8) is flowing upwards through a vertical pipe line which tapers from300mm to 150mm diameter.A gasoline mercury differential manometer is connected between 300 mm and 150 mm pipe sections to measure the rate of flow. The distance between the manometer tappings is 1meter and the gauge heading is 500 mm of mercury. Find the (i) differential gauge reading in terms of gasoline head (ii) rate of flow. Assume frictional and other losses are negligible.[JUN – 2007, 2014, DEC 12] 1.254)Water enters a reducing pipe horizontally and comes out vertically in the downward direction. If the inlet velocity is 5 m/s and pressure is 80 kPa (gauge) and the diameters at the entrance and exit sections are 30 cm and 20 cm respectively, calculate the components of the reaction acting on the pipe. [JUN – 07, DEC 12] 1.255)A horizontal pipe has an abrupt expansion from 10 cm to 16 cm. The water velocity in the smaller section is 12 m/s, and the flow is turbulent. The pressure in the smaller section is 300 kPa. Determine the downstream pressure, and estimate the error that would have occurred if Bernoulli’s equation had been used. [DEC 11] 1.256)Air flows through a pipe at a rate of 20 L/s. The pipe consists of two sections of diameters20 cm and 10 cm with a smooth reducing section that connects them. The pressure difference between the two pipe sections is measured by a water manometer. Neglecting frictional effects, determine the differential height of water between the two pipe sections. Take the air density to be 1.20 kg/m3.[MAY 08]

1.257)A horizontal venturimeter with inlet diameter 200 mm and throat diameter 100 mm is employed to measure the flow of water.The reading of the differential manometer connected to the inlet is 180 mm of mercury. If Cd = 0.98, determine the rate of flow. [MAY 10] 1.258)A horizontal venturimeter of specification 200mm * 100mm is used to measure the discharge of an oil of specific gravity 0.8. A mercury manometer is used for the purpose. If the discharge is 100 litres per second and the coefficient of discharge of meter is 0.98, find the manometer deflection. [JUN 07] 1.259)Determine the pressure difference between inlet and throat of a vertical venturimeter of size 150 mm x 75 mm carrying oil of S = 0.8 at flow rate of 40 lps. The throat is 150 mm above the inlet. 1.260)A pipe of 300 mm diameter inclined at 30° to the horizontal is carrying gasoline (specific gravity = 0.82). A venturimeter is fitted in the pipe to find out the flow rate whose throat diameter is 150 mm. The throat is 1.2 m from the entrance along its length. The pressure gauges fitted to the venturimeter read 140 kN/m2and

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 14

8 0 k N /m2respectively. Find o u t t h e c o -efficient o f d i s c h a r g e o f venturimeter if the flow is 0.20 m3/s. [MAY 10] 1.261)A venturimeter of throat diameter 0.085m is fitted in a 0.17m diameter vertical pipe in which liquid a relative density 0.85 flows downwards. Pressure gauges ate fitted at the inlet and to the throat sections. The throat being 0.9m below the inlet. Taking the coefficient of the meter as 0.95 find the discharge when the pressure gauges read the same and also when the inlet gauge reads 15000N/m2 higher than the throat gauge. [MAY 11] 1.262)A Venturimeter having inlet and throat diameters 30 cm and 15 cm is fitted in a horizontal diesel pipe line (Sp. Gr. = 0.92) to measure the discharge through the pipe. The venturimeter is connected to a mercury manometer. It was found that the discharge is 8 litres /sec. Find the reading of mercury manometer head in cm. Take Cd =0.96.[DEC 11] 1.263)A venturimeter is inclined at 60° to the vertical and its 150 mm diameter throat is 1.2 m from the entrance along its length. It is fitted to a pipe of diameter 300 mm. The pipe conveys gasoline of S = 0.82 and flowing at 0.215 m3/s upwards. Pressure gauges inserted at entrance and throat show the pressures of 0.141 N/mm2and 0.077 N/mm2respectively. Determine the co-efficient of discharge of the venturimeter. Also determine the reading in mm of differential mercury column, if instead of pressure gauges the entrance and the throat of the venturimeter are connected to the limbs of a U tube mercury manometer.[MAY 04] 1.264)A horizontal venturimeter with inlet and throat diameter 300mm and 100mm respectively is used to measure the flow of water. The pressure intensity at inlet is 130 kN/m2 while the vacuum pressure head at throat is 350 mm of mercury. Assuming 3% head lost between the inlet and throat. Find the value of coefficient of discharge for venturimeter and also determine the rate of flow. [DEC – 04, 05, MAY 10] 1.265)A vertical venturimeter carries a liquid of relative density 0.8 and has inlet throat diameters of 150mm and 75mm. The pressure connection at the throat is 150mm above the inlet. If the actual rate of flow is 40litres/sec and Cd = 0.96, find the pressure difference between inlet and throat in N/m2.[JUN 06] 1.266)A 300 mm x 150 mm venturimeter is provided in a vertical pipeline carrying oil of relative density 0.9, the flow being upwards. The differential U tube mercury manometer shows a gauge deflection of 250 mm. Calculate the discharge of oil, if the co-efficient of meter is 0.98.[DEC 07] 1.267)In a vertical pipe conveying oil of specific gravity 0.8, two pressure gauges have been installed at A and B, where the diameters are 160mm a 80mm respectively. A is 2m above B. The pressure gauge readings have shown that the pressure at B is greater than at A by 0.981 N/cm2. Neglecting all losses, calculate the flow rate. If the gauges at A and B are replaced by tubes filled with the same liquid and connected to a U – tube containing mercury, calculate the difference in the level of mercury in the two limbs of the U – tube.[JUN12] 1.268)Determine the flow rate of oil of S = 0.9 through an orifice meter of size 15 cm diameter fitted in a pipe of 30 cm diameter. The mercury deflection of U tube differential manometer connected on the two sides of the orifice is 50 cm. Assume Cd of orifice meter as 0.64.

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 15

1.269)A submarine moves horizontally in sea and has its axis 15 m below the surface of water. A pitot static tube properly placed just in front of the submarine along its axis and is connected to the two limbs of a U - tube containing mercury. The difference of mercury level is found to be170 mm. Find the speed of submarine knowing that the sp. gr of sea water is 1.026. 1.270)A submarine fitted with a Pitot tube move horizontally in sea. Its axis is 20m below surface of water. The Pitot tube placed in front of the submarine along its axis is connected to a differential mercury manometer showing the deflection of 20cm. Determine the speed of the submarine.[MAY 05] 1.271)A pitot-static probe is used to measure the velocity of an aircraft flying at 3000 m. If the differential pressure reading is 3 kPa, determine the velocity of the aircraft. [MAY 08] 1.272)A 15 cm diameter vertical pipe is connected to 10 cm diameter vertical pipe with a reducing socket. The pipe carries a flow of 1001/s. At point 1 in 15 cm pipe gauge pressure is 250 kPa. At point 2 in the 10 cm pipe located 1.0 m below point 1 the gauge pressure is 175 kPa. Find whether the flow is upwards / downwards and Head loss between the two points. 1.273)Water enters a reducing pipe horizontally and comes out vertically in the downward direction. If the inlet velocity is 5 m/sec and pressure is 80 kPa (gauge) and the diameters at the entrance and exit sections are 300 mm and 200 mm respectively. Calculate the components of the reaction acting on the pipe.

UNIT - II - FLOW THROUGH CIRCULAR CONDUCTS PART - A

2.1)How are fluid flows classified? [JUN 12] 2.2)Write down Hagen Poiseuille’s equation for viscous flow through a pipe. 2.3)Write down Hagen Poiseuille’s equation for laminar flow.[MAY 05, DEC 12] 2.4)Write the Hagen – Poiseuille’s Equation and enumerate its importance.[MAY 11] 2.5)State Hagen – Poiseuille’s formula for flow through circular tubes.[JUN 12] 2.6)Write down the Darcy - Weisbach’s equation for friction loss through a pipe [DEC 09, MAY 11] 2.7)What is the relationship between Darcy Friction factor, Fanning Friction Factor and Friction coefficient?[JUN12] 2.8)Mention the types of minor losses.[MAY 10] 2.9)List the minor losses in flow through pipe.[MAY 05, JUN 07] 2.10)What are minor losses? Under what circumstances will they be negligible?[JUN12] 2.11)Distinguish between the major loss and minor losses with reference to flow through pipes. [JUN 09] 2.12)List the causes of minor energy losses in flow through pipes.[DEC09] 2.13)What are the losses experienced by a fluid when it is passing through a pipe? 2.14)What is a minor loss in pipe flows? Under what conditions does a minor loss become a major loss? 2.15)What do you understand by minor energy losses in pipes?[DEC 08] 2.16)List out the various minor losses in a pipeline

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 16

2.17)What are ‘major’ and ‘minor losses’ of flow through pipes? [JUN 07, DEC 07, 12, MAY 10] 2.18)List the minor and major losses during the flow of liquid through a pipe. [MAY 08] 2.19)Enlist the various minor losses involved in a pipe flow system.[DEC 08] 2.20)What factors account in energy loss in laminar flow. [JUN 12] 2.21)Differentiate between pipes in series and pipes in parallel.[DEC 06] 2.22)What is Darcy's equation? Identify various terms in the equation.[MAY 11] 2.23)What is the relation between Darcy friction factor, fanning friction factor and friction coefficient?[DEC 10] 2.24)When is the pipe termed to be hydraulically rough?[DEC 09] 2.25)What is the physical significance of Reynold's number?[JUN, DEC 07] 2.26)Define Reynolds Number.[DEC 12] 2.27)Write the Navier's Stoke equations for unsteady 3 - dimensional, viscous, incompressible and irrotational flow. [MAY 08] 2.28)Define Moody’s diagram 2.29)What are the uses of Moody’s diagram? [DEC08, 2012] 2.30)Write down the formulae for loss of head due to (1). sudden enlargement in pipe diameter (2). Sudden contraction in pipe diameter and (3). Pipe fittings. 2.31)Define (i) relative roughness and (ii) absolute roughness of a pipe inner surface. 2.32)How does surface roughness affect the pressure drop in a pipe if the flow is turbulent? [DEC 13] 2.33)A piping system involves two pipes of different diameters (but of identical length, material, and roughness) connected in parallel. How would you compare the flow rates and pressure drops in these two pipes?[DEC 13] 2.34)What do you mean by flow through parallel pipes?[JUN 13] 2.35)What is equivalent pipe? 2.36)What is the use of Dupuit’s equations? 2.37)What is the condition for maximum power transmission through a pipe line? 2.38)Give the expression for power transmission through pipes?[DEC 08] 2.39)Write down the formula for friction factor of pipe having viscous flow. 2.40)Define boundary layer and boundary layer thickness.[DEC – 2007, 2012] 2.41)Define boundary layer thickness.[JUN 06, DEC 09] 2.42)What is boundary layer? Give its sketch of a boundary layer region over a flat plate. [MAY 03] 2.43)What is boundary layer? Why is it significant? [DEC 09] 2.44)Define boundary layer and give its significance. [MAY 10] 2.45)What is boundary layer and write its types of thickness?[DEC – 2005, 2006] 2.46)What do you understand by the term boundary layer? [DEC 08] 2.47)Define the following (i) laminar boundary layer (ii) turbulent boundary layer

(iii) Laminar sub layer.

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 17

2.48)What is a laminar sub layer? [DEC 10] 2.49)Define momentum thickness and energy thickness. [JUN – 2007, 2012] 2.50)Define the term boundary layer.[JUN 09] 2.51)Define the terms boundary layer, boundary thickness. [DEC 08] 2.52)What is boundary layer separation?[DEC 12] 2.53)Define the following:

(i) Displacement thickness ( ii) Momentum thickness (iii) Energythickness. 2.54)What do you mean by displacement thickness and momentum thickness?[DEC08] 2.55)What do you understand by hydraulic diameter? [DEC 11] 2.56)What is hydraulic gradient line? [JUN 09] 2.57)Define hydraulic gradient line and energy gradient line. 2.58)Brief on HGL. [MAY 11] 2.59)Differentiate between Hydraulic gradient line and total energy line. [DEC 03, MAY 05, 2010, JUN–2007, 2009] 2.60)What is T.E.L?[DEC 09] 2.61)Distinguish between hydraulic and energy gradients. [DEC 11] 2.62)Differentiate hydraulic gradient line and energy gradient line.[JUN 14] 2.63)What are stream lines, streak lines and path lines in fluid flow?[DEC –2006, 2009] 2.64)What do you mean by Prandtl’s mixing length? 2.65)Draw the typical boundary layer profile over a flat plate. 2.66)Define flow net.[DEC 08] 2.67)What is flow net and state its use?[MAY 11] 2.68)Define lift. [DEC 05] 2.69)Define the terms: drag and lift.[DEC – 2007, JUN 09] 2.70)Define drag and lift co-efficient. 2.71)Give the expression for Drag coefficient and Lift coefficient.[MAY 11] 2.72)Considering laminar flow through a circular pipe, draw the shear stress and velocity distribution across the pipe section. [DEC 10] 2.73)Considering laminar flow through a circular pipe, obtain an expression for the velocity distribution. [DEC 12] 2.74)A circular and a square pipe are of equal sectional area. For the same flow rate, determine which section will lead to a higher value of Reynolds number.[DEC 11] 2.75)A 20cm diameter pipe 30km long transport oil from a tanker to the shore at 0.01m3/s. Find the Reynolds number to classify the flow. Take the viscosity μ = 0.1 Nm/s2 and density ρ = 900 kg/m3 for oil.[MAY 03] 2.76)Find the loss of head when a pipe of diameter 200 mm is suddenly enlarged to a diameter 0f 400 mm. Rate of flow of water through the pipe is 250 litres/s.[MAY 10]

PART - B 2.77)What are the various types of fluid flows? Discuss [DEC 10] 2.78)Define minor losses. How they are different from major losses?[JUN 09] 2.79)Discuss on various minor losses in pipe flow. [DEC 13]

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 18

2.80)Which has a greater minor loss co-efficient during pipe flow: gradual expansion or gradual contraction? Why?[MAY 08] 2.81)Derive Chezy’s formula for loss of head due to friction in pipes.[DEC 12] 2.82)What is the hydraulic gradient line? How does it differ from the total energy line? Under what conditions do both lines coincide with the free surface of a liquid? [MAY 08] 2.83)Write notes on the following: (1) Concept of boundary layer. 2. Hydraulic gradient 3. Moody diagram. 2.84)Briefly explain Moody’s diagram regarding pipe friction [JUN 14] 2.85)For a flow of viscous fluid flowing through a circular pipe under laminar flow conditions, show that the velocity distribution is a parabola. And also show that the average velocity is half of the maximum velocity. [JUN 13] 2.86)For flow of viscous fluids through an annulus derive the following expressions: 1. Discharge through the annulus. 2. Shear stress distribution. [JUN – 2007, 2012] 2.87)For a laminar flow through a pipe line, show that the average velocity is half of the maximum velocity. 2.88)Prove that the Hagen-Poiseuille’s equation for the pressure difference between two sections 1 and 2 in a pipe is given by with usual notations. 2.89)Derive Hagen – Poiseuille’s equation and state its assumptions made.[DEC 05] 2.90)Derive Hagen – Poiseuille’s equation [DEC 08] 2.91)Obtain the expression for Hagen – Poiseuille’s flow. Deduce the condition of maximum velocity.[DEC 07] 2.92)Give a proof a Hagen – Poiseuille’s equation for a fully – developed laminar flow in a pipe and hence show that Darcy friction coefficient is equal to 16/Re, where Re is Reynold’s number. [JUN 12] 2.93)Derive an expression for head loss through pipes due to friction.[MAY 10] 2.94)Explain Reynold’s experiment to demonstrate the difference between laminar flow and turbulent flow through a pipe line. 2.95)Derive Darcy - Weisbach formula for calculating loss of head due to friction in a pipe. [DEC 11] 2.96)Derive Darcy - Weisbach formula for head loss due to friction in flow through pipes. [DEC 05] 2.97)Obtain expression for Darcy – Weisbach friction factor f for flow in pipe. [JUN 12] 2.98)Explain the losses of energy in flow through pipes.[DEC 09] 2.99)Derive an expression for Darcy – Weisbach formula to determine the head loss due to friction. Give an expression for relation between friction factor ‘f’ and Reynolds’s number ‘Re’ for laminar and turbulent flow.[MAY 03] 2.100)Prove that the head lost due to friction is equal to one third of the total head at inlet for maximum power transmission through pipes.[DEC 08] 2.101)Show that for laminar flow, the frictional loss of head is given by

hf= 8 fLQ2/gπ2D5 [DEC 09] 2.102)Derive Euler’s equation of motion for flow along a stream line. What are the

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 19

assumptions involved. [DEC09] 2.103)A uniform circular tube of bore radius R1 has a fixed co axial cylindrical solid core of radius R2. An incompressible viscous fluid flows through the annular passage under a pressure gradient (-∂p/∂x). Determine the radius at which shear stress in the stream is zero, given that the flow is laminar and under steady state condition. [JUN 09] 2.104)If the diameter of the pipe is doubled, what effect does this have on the flow rate for a given head loss for laminar flow and turbulent flow.[MAY 11] 2.105)Derive an expression for the variation of jet radius r with distance y downwards for a jet directed downwards. The initial radius is R and the head of fluid is H. [DEC 11] 2.106)Distinguish between pipes connected in series and parallel.[DEC 05] 2.107)Determine the equivalent pipe corresponding to 3 pipes in series with lengths and diameters l1, l2, l3, d1, d2, d3 respectively. [DEC09] 2.108)For sudden expansion in a pipe flow, work out the optimum ratio between the diameter of before expansion and the diameter of the pipe after expansion so that the pressure rise is maximum.[JUN12] 2.109)Obtain the condition for maximum power transmission through a pipe line. 2.111) Explain stream lines, path lines and flow net.[DEC 12] 2.110)What are the uses and limitations of flow net? [JUN 09] 2.111)Briefly explain about boundary layer separation. [DEC 08] 2.112)Explain on boundary layer separation and its control. 2.113)Considering a flow over a flat plate, explain briefly the development of hydrodynamic boundary layer.[DEC 10] 2.114)Discuss in detail about boundary layer thickness and separation of boundary layer. [MAY 11] 2.115)What is boundary layer and write its types of thickness?[MAY 03] 2.116)Explain in detail 1. Drag and lift coefficients 2. Boundary layer thickness 3. Boundary layer separation 4. Navier’s – strokes equation.[JUN12] 2.117)In a water reservoir flow is through a circular hole of diameter D at the side wall at a vertical distance H from the free surface. The flow rate through an actual hole with a sharp-edged entrance (k= 0.5) will be considerably less than the flow rate calculated assuming frictionless flow. Obtain a relation for the equivalent diameter of the sharp-edged hole for use in frictionless flow relations.[DEC 11] 2.118)Define: Boundary layer thickness (δ); Displacement thickness (δ*); Momentum thickness (θ) and energy thickness (δ**). [MAY 10] 2.119)Briefly explain the following terms

1. Displacement thickness 2. Momentum thickness 3. Energy thickness [JUN 14] 2.120)Find the displacement thickness momentum thickness and energy thickness for the velocity distribution in the boundary layer given by (u/v) = (y/δ), where ‘u’ is the velocity at a distance ‘y’ from the plate and u=U at y=δ, where δ = boundary layer

CE6451 – FLUID MECHANICS AND MACHINERY QUESTION BANK 20

thickness. Also calculate (δ*/θ). [DEC07, MAY 10] 2.121)Explain the concept of boundary layer in pipes for both laminar and turbulent flows with neat sketches.[DEC 13] 2.122)Derive an expression for the velocity distribution for viscous flow through a circular pipe. [JUN 07] 2.123)Write a brief note on velocity potential function and stream function. [JUN09] 2.127) Derive an expression for the velocity distribution for viscous flow through a circular pipe. Also sketch the distribution of velocity cross section of the pipe. [DEC11]

PROBLEMS 2.124)A 20 cm diameter pipe 30 km long transports oil from a tanker to the shore at 0.01m3/s. Find the Reynold’s number to classify the flow. Take viscosity and density for oil. 2.125)A pipe line 20cm in diameter, 70m long, conveys oil of specific gravity 0.95 and viscosity 0.23 N.s/m2. If the velocity of oil is 1.38m/s, find the difference in pressure between the two ends of the pipe. [JUN 12] 2.126)Oil of absolute viscosity 1.5 poise and density 848.3kg/m3 flows through a 300mm pipe. If the head loss in 3000 m, the length of pipe is 200m, assuming laminar flow, find (i) The average velocity, (ii) Reynolds’s number and (iii) Friction factor.[JUN12] 2.127)An oil of specific gravity 0.7 is flowing through the pipe diameter 30cm at the rate of 500litres/sec. Find the head lost due to friction and power required to maintain the flow for a length of 1000m. Take γ = 0.29 stokes.[DEC – 2008, JUN09] 2.128)A pipe line 10km, long delivers a power of 50kW at its outlet ends. The pressure at inlet is 5000kN/m2 and pressure drop per km of pipeline is 50kN/m2. Find the size of the pipe and efficiency of transmission. Take 4f = 0.02. [DEC 05] 2.129)A lubricating oil flows in a 10 cm diameter pipe at 1 m/s. Determine whether the flow is laminar or turbulent. 2.130)For the lubricating oil 2 μ = 0.1Ns /m and ρ = 930 kg/m3. Calculate also transition and turbulent velocities.[MAY 11]

2.131)Oil of ,mass density 800kg/m3 and dynamic viscosity 0.02 poise flows through 50mm diameter pipe of length 500m at the rate of 0.19 L/ sec. Determine 1. Reynolds number of flow 2. Center line of velocity 3. Pressure gradient 4. Loss of pressure in 500m length 5. Wall shear stress 6. Power required to maintain the flow. [JUN 12] 2.132)In fully developed laminar flow in a circular pipe, the velocity at R/2 (midway between the wall surface and the center line) is measured to be 6m/s. Determine the velocity at the center of the pipe.[MAY 08] 2.133)A pipe 85m long conveys a discharge of 25litres per second. If the loss of head is 10.5m. Find the diameter of the pipe take friction factor as 0.0075.[DEC 09] 2.134)A smooth pipe carries 0.30m3/s of water discharge with a head loss of 3m per

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100m length of pipe. If the water temperature is 20°C, determine diameter of the pipe. [JUN 12] 2.135)Water is flowing through a pipe of 250 mm diameter and 60 m long at a rate of 0.3 m3/sec. Find the head loss due to friction. Assume kinematic viscosity of water 0.012 stokes. 2.136)Consider turbulent flow (f = 0.184 Re-0.2) of a fluid through a square channel with smooth surfaces. Now the mean velocity of the fluid is doubled. Determine the change in the head loss of the fluid. Assume the flow regime remains unchanged. What will be the head loss for fully turbulent flow in a rough pipe? [DEC 13] 2.137)A pipe of 12cm diameter is carrying an oil (μ = 2.2 Pa.s and ρ = 1250 kg/m3) with a velocity of 4.5 m/s. Determine the shear stress at the wall surface of the pipe, head loss if the length of the pipe is 25 m and the power lost.[DEC 11] 2.138)Find the head loss due to friction in a pipe of diameter 30cm and length 50cm, through which water is flowing at a velocity of 3m/s using Darcy’s formula.[DEC 08] 2.139)For a turbulent flow in a pipe of diameter 300 mm, find the discharge when the center-line velocity is 2.0 m/s and the velocity at a point 100 mm from the center as measured by pitot-tube is 1.6 m/s.[MAY 10] 2.140)A laminar flow is taking place in a pipe of diameter 20cm. The maximum velocity is 1.5m/s. Find the mean velocity and radius at which this occurs. Also calculate the velocity at 4cm from the wall pipe.[JUN09] 2.141)Water is flowing through a rough pipe of diameter 60 cm at the rate of 600litres/second. The wall roughness is 3 mm.Find the power loss for 1 km length of pipe. 2.142)Water flows in a 150 mm diameter pipe and at a sudden enlargement, the loss of head is found to be one-half of the velocity head in 150 mm diameter pipe. Determine the diameter of the enlarged portion. 2.143)A 150mm diameter pipe reduces in diameter abruptly to 100mm diameter. If the pipe carries water at 30 liters per second, calculate the pressure loss across the contraction. The coefficient of contraction as 0.6.[DEC 12] 2.144)A pipe line carrying oil of specific gravity 0.85, changes in diameter from 350mm at position 1 to 550mm diameter to a position 2, which is at 6m at a higher level. If the pressure at position 1 and 2 are taken as 20N/cm2 and 15N/cm2

respectively and discharge through the pipe is 0.2m3/s. Determine the loss of head. [JUN 07]

2.145)A pipe line carrying oil of specific gravity 0.87, changes in diameter from 200mm at position A to 500mm diameter to a position B, which is at 4m at a higher level. If the pressure at position A and B are taken as 9.81N/cm2 and 5.886N/cm2 respectively and discharge through the pipe is 200 litres/s. Determine the loss of head and direction of flow.[DEC 08] 2.146)A 30cm diameter pipe of length 30cm is connected in series to a 20 cm

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diameter pipe of length 20cm to convey discharge. Determine the equivalent length of pipe diameter 25cm, assuming that the friction factor remains the same and the minor losses are negligible.[MAY 03] 2.147)A pipe of 0.6m diameter is 1.5 km long. In order of augment the discharge, another line of the same diameter is introduced parallel to the first in the second half of the length. Neglecting minor losses. Find the increase in discharge, if friction factor f= 0.04. The head at inlet is 40m.[DEC – 2004, 2005, 2012] 2.148)A pipe of 10 cm in diameter and 1000 m long is used to pump oil of viscosity 8.5 poise and specific gravity 0.92 at the rate of1200 L/min. The first 30 m of the pipe is laid along the ground sloping upwards at 10° to the horizontal and remaining pipe is laid on the ground sloping upwards 15° to the horizontal. State whether the flow is laminar or turbulent? Determine the pressure required to be developed by the pump and the power required for the driving motor if the pump efficiency is 60%. Assume suitable data for friction factor, if required. [DEC 10] 2.149)Oil with a density of 900 kg/m3and kinematic viscosity of 6.2×10-4m2is being discharged by a 6 mm dia, 40 m long horizontal pipe from a storage tank open to the atmosphere. The height of the liquid level above the center of the pipe is 3 m. Neglecting the minor losses, determine the flow rate of oil through the pipe.[DEC 11] 2.150)The velocity of water in a pipe 200mm diameter is 5m/s. The length of the pipe is 500m. Find the loss of head due to friction, if f = 0.008.[DEC 05] 2.151)A 200mm diameter (f = 0.032) 175m long discharges a 65mm diameter water jet into the atmosphere at a point which is 75m below the water surface at intake. The entrance to the pipe is reentrant with ke = 0.92 and the nozzle loss coefficient is 0.06. Find the flow rate and the pressure head at the base of the nozzle. [MAY 11] 2.152)A pipe line 2000m long is used for power transmission 110kW is to be transmitted through a pipe in which water is having a pressure of 5000kN/m2 at inlet is flowing. If the pressure drop over a length of a pipe is 1000kN/m2 and coefficient of friction is 0.0065, find the diameter of the pipe and efficiency of transmission. [JUN12] 2.153)A horizontal pipe of 400 mm diameter is suddenly contracted to a diameter of 200 mm. The pressure intensities in the large and small pipe are given as 15 N/cm2 and 10 N/cm2 respectively. Find the loss of head due to contraction, if Cc = 0.62, determine also the rate of flow of water. 2.154)A horizontal pipe line 40 m long is connected to a water tank at one end and discharges freely into the atmosphere at the other end. For the first 25 m of its length from the tank, the pipe is 150 mm diameter and its diameter is suddenly enlarged to 300 mm. The height of water level in the tank is 8 m above the centre of the pipe. Considering all losses of head which occur, determine the rate of flow. Take f = 0.01 for both sections of the pipe. [JUN 13] 2.155)A 15cm diameter vertical pipe is connected to 10cm diameter vertical pipe with a

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reducing socket. The pipe carries a flow of 100 l/s. At a point 1 in 15cm pipe gauge pressure is 250kPa. At point 2 in the 10cm pipe located 1m below point 1 the gauge pressure is 175kPa. Find weather the flow is upwards /downwards & Head loss between the two points[DEC08] 2.156)The rate of flow of water through a horizontal pipe is 0.25 m3/sec. The diameter of the pipe, which is 20 cm, is suddenly enlarged to 40 cm. The pressure intensity in the smaller pipe is 11.7 N/cm2. Determine the loss of head due to sudden enlargement and pressure intensity in the larger pipe, power loss due to enlargement. [JUN 0 9 ] 2.157)A 45° reducing bend is connected to a pipe line. The inlet and outlet diameters of the bend being 600mm and 300mm respectively. Find the force exerted by water on the bend, if the intensity of pressure at inlet to bend is 8.829N/cm2 and the rate of flow of water is 600 liters/s. [DEC 07] 2.158)Horizontal pipe carrying water is gradually tapering. At one section the diameter is 150mm and the flow velocity is 1.5m/s. If the drop pressure is 1.104bar is reduced section, determine the diameter of that section. If the drop is 5kN/m2, what will be the diameter – Neglect the losses? [DEC 09] 2.159)The rate of flow of water through a horizontal pipe is 0.3m3/sec. The diameter of the pipe, which is 25cm, is suddenly enlarged to 50 cm. The pressure intensity in the smaller pipe is 14N/cm2. Determine the loss of head due to sudden enlargement, pressure intensity in the larger pipe power lost due to enlargement. [DEC 03] 2.160)Water at 15°C ( ρ =999.1 kg/m3and μ = 1.138 x 10-3kg/m. s) is flowing steadily in a30-m-long and 4 cm diameter horizontal pipe made of stainless steel at a rate of 8 L/s. Determine (i) the pressure drop, (ii) the head loss, and (iii) the pumping power requirement to overcome this pressure drop. Assume friction factor for the pipe as 0.015. [MAY 08] 2.161)The discharge of water through a horizontal pipe is 0.25m3/s. The diameter of above pipe which is 200mm suddenly enlarges to 400mm at a point. If the pressure of water in the smaller diameter of pipe is 120kN/m2, determine loss of head due to sudden enlargement; pressure of water in the larger pipe and the power lost due to sudden enlargement. [JUN 09] 2.162)A pipe of varying sections has a sectional area of 3000, 6000 and 1250 mm2 at point A, B and C situated 16 m, 10 m and 2 m above the datum. If the beginning of the pipe is connected to a tank which is filled with water to a height of 26 m above the datum, find the discharge, velocity and pressure head at A, B and C. Neglect all losses. Take atmospheric pressure as 10 m of water. 2.163)An existing 300mm diameter pipeline of 3200m length connects two reservoirs having 13m difference in their water levels. Calculate the discharge Q1. If a parallel pipe 300mm in diameter is attached to the last 1600m length of the above existing pipe line, find the new discharge Q2. What is the change in discharge? Express it as a % of

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Q1. Assume friction factor f = 0.14 in Darcy – Weisbach formula.[JUN 09] 2.164)Two reservoirs with a difference in water surface elevation of 15 m are connected by a pipe line ABCD that consists of three pipes AB, BC and CD joined in series. Pipe AB is 10 cm in diameter, 20 m long and has f = 0.02. Pipe BC is of 16 cm diameter, 25 m long and has f = 0.018. Pipe CD is of 12 cm diameter, 15 m long and has f = 0.02. The junctions with the reservoirs and between the pipes are abrupt. (a) Calculate the discharge (b) What difference in reservoir elevation is necessary to have a discharge of 20 litres/sec? Include all minor losses. 2.165)Two tanks of fluid ( ρ = 998 kg/m3 and µ = 0.001 kg/ms.) at 20°C are connected by a capillary tube 4 mm in diameter and 3.5 m long. The surface of tank 1 is 30 cm higher than the surface of tank 2. Estimate the flow rate in m3/h. Is the flow laminar? For what tube diameter will Reynolds number be 500?[DEC 13] 2.166)Three pipes of 400mm, 350mm and 300mm diameter connected in series between two reservoirs. With difference in level of 12m. Friction factor is 0.024, 0.021 and 0.019 respectively. The lengths are 200m, 300m and 250m. Determine flow rate neglecting the minor losses.[DEC 09] 2.167)Three pipes of diameters 300 mm, 200 mm and 400 mm and lengths450 m, 255 m and 315 m respectively are connected in series. The difference in water surface levels in two tanks is 18 m. Determine the rate of flow of water if coefficients of friction are 0.0075, 0.0078and 0.0072 respectively considering: the minor losses and by neglecting minor losses.[DEC 11] 2.168)Three pipes of diameters 300 mm, 200 mm and 400 mm and lengths 300 m, 170 m and 210 m respectively are connected in series. The difference in water surface levels in two tanks is 12 m. Determine the rate of flow of water if coefficients of friction are 0.005, 0.0052 and 0.0048 respectively considering: the minor losses and by neglecting minor losses[JUN– 2012] 2.169)Three pipes connected in series to make a compound pipe. The diameters and lengths of pipes are respectively, 0.4m, 0.2m, 0.3m and 400m, 200m, 300m. The ends of the compound pipe are connected to 2 reservoirs whose difference in water levels is 16m. The friction factor for all the pipes is same and equal to 0.02. The coefficient of contraction is 0.6. Find the discharge through the compound pipe if, minor losses are negligible. Also find the discharge if minor losses are included. [DEC 10] 2.170)A compound piping system consists of 1800 m of 0.5 m, 1200 m of 0.4 m and 600 m of 0.3 m new cast-iron pipes connected in series. Convert the system to (i) an equivalent length of0.4 m diameter pipe and (ii) an equivalent size of pipe of 3600 m length. [MAY 03] 2.171)A pipe line of 600 mm diameter is 1.5 km long. To increase the discharge, another line of the same diameter is introduced parallel to the first in the second half of the length. If f = 0.01 and head at inlet is 30 m, calculate the increase in discharge.

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2.172)A pipe line of 0.6m diameter is 1.5Km long. To increase the discharge, another line of same diameter is introduced in parallel to the first in second half of the length. Neglecting the minor losses, find the increase in discharge if 4f = 0.04. The head at inlet is 30cm. [MAY 11] 2.173)Two pipes of 15cm and 30cm diameters are laid in parallel to pass a total discharge of 100 litres per second. Each pipe is 250m long. Determine discharge through each pipe. Now these pipes are connected in series to connect two tanks 500m apart, to carry same total discharge. Determine water level difference between the tanks. Neglect the minor losses in both cases, f=0.02 fn both pipes.[JUN07] 2.174)Two pipes of diameter 40 cm and 20 cm are each 300 m long. When the pipes are connected in series and discharge through the pipe line is0.10 m3/sec, find the loss of head incurred. What would be the loss of head in the system to pass the same total discharge when the pipes are connected in parallel? Take f = 0.0075 for each pipe. [JUN – 2007, 2012, DEC 10] 2.175)A main pipe divides into two parallel pipes, which again forms one pipe. The length and diameter for the first parallel pipe are 2000m and 1m respectively, while the length and diameter of second parallel pipe are 200m and 0.8m respectively. Find the rate of flow in each parallel pipe, if total flow in the main is 3m3/s. The coefficient of friction for each parallel pipe is same and equal to 0.005.[JUN 07] 2.176)The main pipe is divided into two parallel pipes which again forms one pipe, the first parallel pipe has length of 1000 m and diameter of 0.8 m. The second parallel pipe has length of 1000 m and diameter of 0.6 m. The coefficient friction for each parallel pipe is 0.005. If the total rate of flow in the main pipe is 2 m3 /sec, find the rate of flow in each parallel pipe.[JUN 14] 2.177)For a town water supply, a main pipe line of diameter 0.4 m is required. As pipes more than 0.35m diameter are not readily available, two parallel pipes of same diameter are used for water supply. If the total discharge in the parallel pipes is same as in the single main pipe, find the diameter of parallel pipe. Assume co- efficient of discharge to be the same for all the pipes.[MAY 10] 2.178)Two pipes of identical length and material are connected in parallel. The diameter of pipe A is twice the diameter of pipe B. Assuming the friction factor to be the same in both cases and disregarding minor losses, determine the ratio of the flow rates in the two pipes.[MAY 08] 2.179)A pipe line 30cm in diameter and 3.2m long is used to pump up 50Kg per second of oil whose density is 950 Kg/m3 and whose kinematic viscosity is 2.1 strokes, the center of the pipe line at the upper end is 40m above than the lower end. The discharge at the upper end is atmospheric. Find the pressure at the lower end and draw the hydraulic gradient and total energy line. [MAY 11] 2.180)Two water reservoirs A and B are connected to each other through a 50 m long, 2.5 cm Φ C.I pipe with a sharp-edged entrance. The pipe also involves a swing check valve and a fully open gate valve. The water level in both reservoirs is the same, but

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reservoir A is pressurized by compressed air while reservoir B is open to the atmosphere. If the initial flow rate through the pipe is 1.5l/s, determine the absolute air pressure on top of reservoir A Take the water temperature to be 25°C. [DEC11] 2.181)When water is being pumped is a pumping plant through a 600mm diameter main, the friction head was observed as 27m. In order to reduce the power consumption, it is proposed to lay another main of appropriate diameter along the side of existing one, so that the two pipes will work in parallel for the entire length and reduce the friction head to 9.6m only. Find the diameter of the new main if with the exception of diameter; it is similar to the existing one in all aspects.[DEC 07] 2.182)Determine the Pressure gradient The shear stress at the two horizontal parallel plates and Discharge per meter width for the laminar flow of oil with maximum velocity 2m/s

between two horizontal parallel fixed plates which are 10cm apart. Given μ = 2.4525 Ns/m2 [MAY 11]

2.183)In fully developed laminar flow in a circular pipe, the velocity at R/2 (midway between the wall surface and the centerline) is measured to be 6 m/s. Determine the velocity at the center of the pipe.[MAY 08] 2.184)A smooth two –dimensional flat plate is exposed to a wind velocity of 100 km/h. If laminar boundary layer exists up to a value of Rexequal to 3 x 105, find the maximum distance up to which laminar boundary layer exists and find its maximum thickness. Assume kinematic viscosity of air as 1.49 x 10-5m2/s. [MAY 03] 2.185)Air is flowing over a flat plate with a velocity of 5 m/s. The length of the plate is 2.5 m and width 1 m. The kinematic viscosity of air is given as 0.15 x 10-4m2/s.

Find the (i) boundary layer thickness at the end of plate (ii) shear stress at 20 cm from the leading edge (iii) shear stress at 175 cm from the leading edge (iv) Drag force on one side of the plate. (v) Take the velocity profile over a plate as and the density of air1.24

kg/m3. 2.186)A plate of 600mm length and 400mm wide is immersed in a fluid of specific gravity 0.9 and kinematic viscosity of = 10-4 m2/s. The fluid is moving with velocity of 6m/s. Determine

Boundary layer thickness Shear stress at the end of the plate

2.187)Drag force on one side of the plate. [DEC 12] 2.188)Water at 20° C enters a pipe with a uniform velocity (U) of 3m/s. What is the distance at which the transition (x) occurs from a laminar to a turbulent boundary

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layer? If the thickness of this initial laminar boundary layer is given by 4.91√(vx/U) what is its thickness at the point of transition?(v – kinematic viscosity).[MAY 11] 2.189)A flat plate 1.5 m x 1.5 m moves at 50 km/h in stationary air of density 1.15 kg/m3. If the co-efficient of drag and lift are 0.15 and 0.75 respectively, determine The Lift force, Drag force, the resultant force and the power required to set the plate in motion. [DEC 07]

2.190)A jet plane which weighs 29430 N and has the wing area of 20m2 flies at the velocity of 250km/hr. When the engine delivers 7357.5kW. 65% of power is used to overcome the drag resistance of the wing. Calculate the coefficient of lift and coefficient of drag for the wing. Take density of air = 1.21 kg/m3[JUN09]

2.191)For the velocity profile in laminar boundary layer as u/U = 3/2 (y/δ)-1/2(y/δ) 3. Find the thickness of the boundary layer and shear stress, 1.8m from the leading edge of a plate. The plate is 2.5 m long and 1.5 m wide is placed in water, which is moving with a velocity of 15 cm/sec. Find the drag on one side of the plate if the viscosity of water is 0.01 poise.[DEC 03] 2.192)Consider flow of oil through a pipe of 0.3m diameter. The velocity distribution is parabolic with maximum velocity of 3 m/s at the pipe centre. Estimate the shear stress at the pipe wall and within the fluid 50mm from the pipe wall. The viscosity of the oil is 1.7Pa.s.[DEC 12] 2.193)The velocity distribution for flow over a plate is given by u = 2y – y2 where u is the velocity in m/sec at a distance y meters above the plate. Determine the velocity gradient and shear stress at the boundary and 0.15m from it. Dynamic viscosity of the fluid is 0.9Ns/m2 [MAY 10] 2.194)The velocity distribution in the boundary layer is given by u/U = y/δ, where u is the velocity at the distance y from the plate u = U at y = δ, δ being boundary layer thickness. Find the displacement thickness, momentum thickness and energy thickness. [MAY 10] 2.195)The flow rate in a 260mm diameter pipe is 220 litres/sec. The flow is turbulent, and the centerline velocity is 4.85m/s. Plot the velocity profile, and determine the head loss per meter of pipe.[MAY 11]

2.196)The velocity distribution over a plate is given by u = (3/4) * y – y2 where u is velocity in m/s and at depth y in m above the plate. Determine the shear stress at a distance of 0.3m from the top of plate. Assume dynamic viscosity of the fluid is taken as 0.95 Ns/m2[MAY 05]

2.197)The velocity distribution over a plate is given by a relation, where y is the vertical distance above the plate in meters. Assuming a viscosity of 0.9Pa.s, find the shear stress at y = 0 and y = 0.15m.[DEC 12]

2.198)An oil of viscosity 0.9Pa.s and density 900kg/m3 flows through a pipe of

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100mm diameter. The rate of pressure drop for every meter length of pipe is 25kPa. Find the oil flow arte, drag force per meter length, pumping power required to maintain the flow over a distance of 1km, velocity and shear stress at 15, from the pipe wall. [DEC 10] 2.199)Consider the flow of a fluid with viscosity m through a circular pipe. The velocity profile in the pipe is given as where is the maximum flow velocity, which occurs at the centerline; r is the radial distance from the centerline; is the flow velocity at any position r; and R is the Reynold's number. Develop a relation for the drag force exerted on the pipe wall by the fluid in the flow direction per unit length of the pipe. [MAY 08]

2.200)Velocity components in flow are given by U = 4x, V = -4y. Determine the stream and potential functions. Plot these functions for φ 60, 120, 180, and 240 and Ф 0, 60, 120, 180, +60, +120, +180. Check for continuity. [DEC 09] 2.201)A fluid of specific gravity 0.9 flows along a surface with a velocity profile given by v = 4y - 8y3m/s, where y is in m. What is the velocity gradient at the boundary? If the kinematic viscosity is 0.36S, what is the shear stress at the boundary? [A.U. DEC 08] 2.202)In a two dimensional incompressible flow the fluid velocities are given by u = x – ay and v = - y – 4x. Show that the velocity potential exists and determine its form. Find also the stream function.[JUN09] 2.203)A smooth flat plate with a sharp leading edge is placed along a free stream of water flowing at 3m/s. Calculate the distance from the leading edge and the boundary thickness where the transition from laminar to turbulent- flow MAY commence. Assume the density of water as 1000 kg/m3 and viscosity as 1centipoise. [MAY 11] 2.204)A smooth two dimensional flat plate is exposed to a wind velocity of 100 km/hr. If laminar boundary layer exists up to a value of RN = 3 x105, find the maximum distance up to which laminar boundary layer persists and find its maximum thickness. Assume kinematic viscosity of air as 1.49x10-5 m2/s.[DEC 08] 2.205)A power transmission pipe 10 cm diameter and 500 m long is fitted with a nozzle at the exit, the inlet is from a river with water level 60 m above the discharge nozzle. Assume f = 0.02, calculate the maximum power which can be transmitted and the diameter of nozzle required. [DEC 08]

\ 4

UNIT - III - DIMENSIONAL ANALYSIS

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PART - A 3.1)What do you understand by fundamental units and derived units?[MAY 10] 3.2)Differentiate between fundamental units and derived units. Give examples.[DEC 11] 3.3)Define dimensional analysis. 3.4)What do you mean by dimensional analysis?[DEC 09] 3.5)Define dimensional homogeneity. 3.6)What is dimensional homogeneity and write any one sample equation?[DEC 06] 3.7)Explain the term dimensional homogeneity.[DEC 11] 3.8)Give the methods of dimensional analysis. 3.9)State a few applications, usefulness of ‘dimensional analysis’.[JUN 07] 3.10)What is a dimensionally homogenous equation? Give example.[DEC 03] 3.11)Cite examplesfordimensionallyhomogeneousandnon-homogeneous equations. [DEC 10] 3.12)Check whether the following equation is dimensionally homogeneous. Q =Cd .a √ (2 gh). [MAY 11] 3.13)Define Rayleigh's method. 3.14)Give the Rayleigh method to determine dimensionless groups.[DEC 11] 3.15)State any two choices of selecting repeating variables in Buckingham π theorem. [MAY 11] 3.16)State Buckingham’s π theorem.[DEC – 2008, 2012] 3.17)What is Buckingham's π theorem? 3.18)The excess pressure Δp inside a bubble is known to be a function of the surface tension and the radius. By dimensional reasoning determine how the excess pressure. Will vary if we double the surface tension and the radius.[DEC 13] 3.19)Distinguish between Rayleigh's method and Buckingham's π- theorem.[MAY 11] 3.20)Under what circumstances, will Buckingham’s π theorem yield incorrect number of dimensionless group? 3.21)State a few applications / usefulness of dimensional analysis. 3.22)Define Euler's number. [JUN 09] 3.23)List out any four rules to select repeating variable. 3.24)Define similitude. 3.25)Give the three types of similarities. 3.26)What are the types of similarities?[DEC 12] 3.27)Define geometric similarity. 3.28)Define kinematic similarity. 3.29)Define dynamic similarity. 3.30)What is meant by dynamic similarity? [DEC08] 3.31)What is dynamic similarity?[DEC 09] 3.32)What is similarity in model study? [MAY 05] 3.33)What is scale effect in physical model study?[DEC – 2005, 2006, JUN– 2012] 3.34)If two systems (model and prototype) are dynamically similar, is it implied that they are also kinematically and geometrically similar? [JUN12]

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3.35)Distinguish between a control and differential control volume.[MAY 11] 3.36)Mention the circumstances which necessitate the use of distorted models.[DEC 10] 3.37)Give the types of forces in a moving fluid. 3.38)Give the dimensions of power and specific weight.[DEC 09] 3.39)Define inertia force. 3.40)Define viscous force. 3.41)Define gravity and pressure force. 3.42)Define surface tension force. 3.43)Define dimensionless numbers. 3.44)Give the types of dimensionless numbers. 3.45)Give the dimensions of the following physical quantities: surface tension and dynamic viscosity.[JUN 13] 3.46)Define Reynolds number. What its significance? [DEC 10] 3.47)Define Reynolds number and Froude’s numbers. [DEC – 2007,2011] 3.48)Define the Froude's dimensionless number. [JUN 14] 3.49)Define Froude's number.[DEC – 2005, 2009, 2008, MAY – 2010, JUN 12] 3.50)State Froude's model law. [JUN 13] 3.51)Define Euler number and Mach number. [JUN 07] 3.52)Define Reynold’s number and Mach number. [DEC 12] 3.53)Define Mach number. [JUN 09] 3.54)What is Mach number? Mention its field of use. [MAY 03] 3.55)Define Mach's number and mention its field of use. 3.56)Write down the dimensionless number for pressure.[DEC 11]

PART - B 3.57)What is repeating variables? How are these selected? [JUN 07] 3.58)State the similarity laws used in model analysis. [MAY 10] 3.59)State and explain the various laws of similarities between model and its prototype. 3.60)What is meant by geometric, kinematic and dynamic similarities? [JUN –07, 2014] 3.61)What is meant by geometric, kinematic and dynamic similarities? Are these similarities truly attainable? If not, why? [JUN 09] 3.62)Explain the different types of similarities exist between a proto type and its model. [DEC 03] 3.63)What is distorted model and also give suitable example?[MAY 04] 3.64)What are distorted models? State merits and demerits. [JUN 14] 3.65)Define dimensional h o m o g e n e i t y and a l s o g i v e e x a m p l e f o r homogenous equation.[MAY 05] 3.66)Classify Models with scale ratios.[DEC 09] 3.67)Derive on the basis of dimensional analysis suitable parameters to present the thrust developed by a propeller. Assume that the thrust P depends upon the angular velocity ω , speed of advance V, diameter D, dynamic viscosity μ, mass density ρ , elasticity of the fluid medium which can be denoted by the speed of sound in the

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medium C. [DEC – 2011, 2012] 3.68)Check the following equations are dimensionally homogenous Drag force = ½ ( Cd ρU2A) where Cd is coefficient of drag which is

constant F = γQ ( U1 – U2) / g – ( P1A1 – P2A2)

Total energy per unit mass = v2/2 + gz + P/ρ Q = δ / 15Cd tan(θ/2) √(2g) * (H)5/2where Cd is coefficient of discharge

constant [MAY 04, 10, DEC 05] 3.69)Define and explain Reynolds number, Froude’s number, Euler’s number and Mach’s number.[DEC03] 3.70)What are the significance and the role of the following parameters?

Reynolds number Froude number Mach number Weber number. [MAY 11]

3.71)Define the following dimensionless numbers and state their significance for fluid flow problems. [JUN 14]

Reynolds number & Mach number 3.72)Explain the Reynolds model law and state its applications. 3.73)Use dimensionless analysis to arrange the following groups into dimensionless parameters; ∆p, V, γ, g and f, ρ, L, V use MLT system.[MAY 11] 3.74)Use dimensional analysis and the MLT system to arrange the following into a dimensionless number: L, ρ, µ and a.[DEC 13] 3.75)Consider force F acting on the propeller of an aircraft, which depends upon the variable U, ρ, μ, D and N. Derive the non – dimensional functional form F/(ρU2D2) = f ((UDρ/μ), (ND/U)) [DEC 03] 3.76)The frictional torque T of a disc diameter D rotating at a speed N in a fluid of viscosity μ and density ρ in a turbulent flow is given by T = D5 N2 ρ Ф[μ/D2Nρ]. Prove this by Buckingham’s π theorem. [DEC03] 3.77)Resistance R, to the motion of a completely submerged body is given by R = ρv2l2φ (VL/γ), where ρ and γ are the mass density and kinematic viscosity of the fluid; v– velocity of flow; l length of the body. If the resistance of a one – eighth scale air - ship model when tested in water at 12m/s is 22N, what will be the resistance of the air –ship at the corresponding aped, in air? Assume kinematic viscosity of air is 13times that of water and density of water is 810 times of air. [DEC 07, MAY 10] 3.78)The resisting force R to a supersonic plane during flight can be considered as dependent upon the length of the aircraft l, velocity V, air viscosity m, air density and bulk modulus of air K. Express the functional relationship between these variables and the resisting force. 3.79)The resisting force F of a plane during flight can be considered as dependent

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upon the length of aircraft (l), velocity (v), air viscosity (μ), air density (ρ) and bulk modulus of air (K). Express the functional relationship between these variables using dimensional analysis. Explain the physical significance of the dimensionless groups arrived. [DEC 10] 3.80)Derive anexpressionfortheshearstress atthepipewall when an incompressible fluid flows through a pipe under pressure. Use dimensional analysis with the following significant parameters: pipe diameter D, flow velocity V, and viscosity µ and density ρ of the fluid. [DEC 13] 3.81)The resistance R, to the motion of a completely submerged body depends upon the length of the body (L), velocity of flow (V), mass density of fluid (ρ), kinematic viscosity (γ). Prove by dimensional analysis that R = ρV2L2φ(VL/γ) [JUN 09] 3.82)The power developed by hydraulic machines is found to depend on the head h, flow rate Q, density ρ, speed N, runner diameter D, and acceleration due to gravity g. Obtain suitable dimensionless parameters to correlate experimental results.[DEC 11] 3.83)Show that the power P developed in a water turbine can be expressed as:

Where, r = Mass density of the liquid, N = Speed in rpm, D = Diameter of the runner, B = Width of the runner and m = Dynamic viscosity[DEC 11] 3.84)The capillary rise h is found to be influenced by the tube diameter D, density ρ, gravitational acceleration g and surface tension σ. Determine the dimensionless parameters for the correlation of experimental results.[DEC 11] 3.85)Using dimensional analysis, obtain a correlation for the frictional torque due to rotation of a disc in a viscous fluid. The parameters influencing the torque can be identified as the diameter, rotational speed, viscosity and density of the fluid.[DEC 11] 3.86)The drag force on a smooth sphere is found to be affected by the velocity of flow, u, the diameter D of the sphere and the fluid properties density ρ and viscosity μ. Find the dimensionless groups to correlate the parameters.[DEC 11] 3.87)State Buckingham's π - theorem. What do you mean by repeating variables? How are the repeating variables selected in dimensional analysis? 3.88)State Buckingham's π - theorem. What are the considerations in the choice of repeating variables?[MAY 10] 3.89)Express efficiency in terms of dimensionless parameters using density, viscosity, angular velocity, dia of rotor and discharge using Buckingham π theorem.[DEC 09] 3.90)State the Buckingham π theorem. What are the criteria for selecting repeating variable in this dimensional analysis?[DEC09] 3.91)State Buckingham – π theorem. Mention the important principle for selecting the repeating variables.[JUN 09] 3.92)State and prove Buckingham π theorem.[DEC – 2009, MAY 10] 3.93)Using Buckingham’s π- theorem show that the velocity through a circular orifice is given by V = √(2gH) φ [(D/H), (μ/ρVH) Where H is the head causing the flow, D is

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the diameter of the orifice, μ is the coefficient of velocity, ρ is the mass density & g is the acceleration due to gravity[DEC 08, MAY 10] 3.94)Using Buckingham's π- theorem, show that the pressure difference DP in a pipe of diameter D and length l due to turbulent flow depends on the velocity V, viscosity m, density and roughness k. 3.95)The efficiency (η) of a fan depends on ρ (density), μ (viscosity) of the fluid, ω (angular velocity), d (diameter of rotor) and Q (discharge). Express η in terms of non-dimensional parameters. Use Buckingham's theorem.[MAY 10, 2011] 3.96)The pressure difference Δp in a pipe of diameter D and length L due to viscos flow depends on the velocity V, viscosity µ and density ρ. Using Buckingham's π theorem, obtain an expression for Δp.[JUN 14] 3.97)The power required by the pump is a function of discharge Q, head H, acceleration due to gravity g, viscosity μ, mass density of the fluid ρ, speed of rotation N and impeller diameter D. Obtain the relevant dimensionless parameters.[JUN 12] 3.98)State Buckingham's π -theorem. The discharge of a centrifugal pump (Q) is dependent on N (speed of pump), d (diameter of impeller), g (acceleration due to gravity), H (manometric head developed by pump) and ρ and µ (density and dynamic viscosity of the fluid). Using the dimensional analysis and Buckingham's π -theorem,

prove that it is given by [JUN 13] 3.99)Consider viscous flow over a very small object. Analysis of the equations of motion shows that the inertial terms are much smaller than viscous and pressure terms. Fluid density drops out, and these are called creeping flows. The only important parameters are velocity U, viscosity µ, and body length scale d. For three-dimensional bodies. Like spheres, creeping flow analysis yields very good results. It is uncertain, however, if creeping flow applies to two-dimensional bodies, such as cylinders, since even though the diameter MAY be very small, the length of the cylinder is infinite. Let us see if dimensional analysis can help. (1) Apply the Pi theorem to two-dimensional drag force F2-D, as a function of the other parameters. Be careful: two-dimensional drag has dimensions of fake per unit length, not simply force. (2) Is your analysis in part (1) physically plausible? If not, explain why not. (3) It turns out that fluid density ρ cannot be neglected in analysis of creeping flow over two dimensional bodies. Repeat the dimensional analysis, this time including ρ as a variable, and find the resulting non dimensional relation between the parameters in this problem. [DEC 13] 3.100)When fluid in a pipe is accelerated linearly from rest, it begins as laminar flow and then undergoes transition to turbulence at a time t, which depends upon the pipe diameter D, fluid acceleration a, density ρ and viscosity µ. Arrange this into a dimensionless relation between t and D.[DEC 13] 3.101)What are thesimilarities betweenmodelandprototype? Mention the applications of model testing.[JUN 13]

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PROBLEMS 3.102)Find the discharge through a weir model by knowing the discharge over the actual (proto type) weir is measured as 1.5m3/s. The horizontal dimension of the model = 1/50 of the horizontal dimensions of the proto type and the vertical dimension of the model = 1/10 of the vertical dimension of the proto type. (Hint: Apply Froude model law) [MAY 04] 3.103)Model of an air duct operating with water produces a pressure drop of 10 kN/m2 over 10 m length. If the scale ratio is 1/50. Density of water is 1000 kg/m3

and density of air is 1.2 kg/m3. Viscosity of water is 01.001 Ns/m2 and viscosity of air 0.00002 Ns/m2. Estimate corresponding drop in a 20m long air duct.[DEC04, 05,MAY10] 3.104)A model of a hydroelectric power station tail race is proposed to build by selecting vertical scale 1 in 50 and horizontal scale 1 in 100. If the design pipe has flow rate of 600m3/s and allow the discharge of 800m3/s. Calculate the corresponding flow rates for the model testing. [MAY 05] 3.105)A pipe of diameter 1.5 m is required to transport an oil of specific gravity 0.90 and viscosity 3 * 10-2 poise at the rate 3000 litre / sec. Test where conducted on a 15cm diameter pipe using water at 20º C. Find the velocity and the rate of flow in model. Viscosity of water at 20ºC = 0.01poise. [DEC12] 3.106)In order to predict the pressure in a large air duct model is constructed with linear dimensions 1/10th that of the prototype and the water was used as the testing fluid. If water is 1000 times denser than that of air and has 100 times the viscosity of air, determine the pressure drop in the prototype, for the conditions corresponding to a pressure drop of 70kPa, in the model.[JUN 09] 3.107)In an aero plane model of size 1/10 of its prototype, the pressure drop is 7.5kN/m2. The model is tested in water; find the corresponding drop in prototype. Assume density of air = 1.24kg/m3; density of water = 1000kg/m3; viscosity of air = 0.00018 poise; viscosity of water = 0.01 poise. [JUN 07] 3.108)A geometrically similar model of an air duct is built to 1/25 scale and tested with water which is 50 times more viscous and 800 times denser than air. When tested under dynamically similar conditions, the pressure drop is 200 kN/m2 in the model. Find the corresponding pressure drop in the full scale prototype and express in cm of water. [DEC – 2010, JUN 14] 3.109)Model tests have conducted to study the energy losses in a pipe line of 1m diameter required to transport kerosene of specific gravity 0.80 and dynamic viscosity 0.02 poise at the rate of 2000 litre/sec. Tests were conducted on a 10cm diameter pipe using water at 20°C. What is the flow rate in the model? If the energy head loss in 30m length of the model is measured as 44cm of water, what will be the corresponding head loss in the prototype? What will be the friction factor for the prototype pipe?[JUN 12]

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3.110)In a geometrically similar model of spillway the discharge per meter length is 0.2m3/sec. if the scale of the model is 1/36, find the discharge per meter run of the prototype. [JUN 14] 3.111)A spillway model is to be built to a geometrically similar scale of 1/50 across a flume of 600 mm width. The prototype is 15 m high and maximum head on it is expected to be 1.5 m.

What height of model and what head on the model should be used? If the flow over the model at a particular head is 12 L per second,

what flow per meter length of the prototype is expected? If the negative pressure in the model is 200 mm, what is the

negative pressure in prototype? Is it practicable? [JUN 13] 3.112)An agitator of diameter D rotates at a speed N in a liquid of density ρ and viscosity μ. Show that the power required to mix the liquid is expressed by a functional

form [MAY 11] UNIT – IV – PUMPS

PART - A 4.1)Define centrifugal pump. 4.2)Mention the main parts of the Centrifugal pump. [DEC 12] 4.3)How centrifugal pumps are classified based on casing? [JUN 06] 4.4)Define impeller. 4.5)Define casing. 4.6)List the commonly used casings in centrifugal pumps. [DEC 10] 4.7)What is the role of a volute chamber of a centrifugal pump?[DEC 05] 4.8)What precautions are to be taken while starting and closing the centrifugal pump? [JUN12] 4.9)Define priming of centrifugal pump. 4.10)What is priming? [DEC 10] 4.11)Why priming is necessary in a centrifugal pump?[JUN 07, MAY 10] 4.12)What is meant by priming of pumps? [MAY 08] 4.13)What is priming? Why is it necessary? [DEC 11] 4.14)Define cavitation. [DEC 08] 4.15)Define cavitation in a pump. [JUN 07] 4.16)What is the effect of cavitation in pump?[MAY 11] 4.17)What are the effectsof cavitation? Givenecessary precautions against cavitation’s? [JUN12] 4.18)What is cavitation? What causes it? [DEC 13] 4.19)Define the characteristic curves of centrifugal pump. 4.20)List out the types of characteristic curves. 4.21)Define multistage centrifugal pump and give its function. 4.22)What are the advantages of centrifugal pump over reciprocating pumps?[JUN 09] 4.23)What is a delivery pipe?

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4.24)Define manometric efficiency and mechanical efficiency of a centrifugal pump. 4.25)What is the maximum theoretical suction head possible for a centrifugal pump? [MAY 08] 4.26)Define suction head and manometric head of a centrifugal pump.[DEC 12] 4.27)Define - manometric head and write its mathematical equation.[DEC 13] 4.28)What do you mean by ‘Net Positive Suction Head’ (NPSH)?[JUN 14] 4.29)How does the specific speed of a centrifugal pump differ from that of a turbine? 4.30)Write the equation for specific speed for pumps and also for turbine.[DEC 05] 4.31)Define specific speed as applied to pumps. [JUN 09] 4.32)Define specific speed. [DEC 07 4.33)What is specific speed of a pump? How are pumps classified based on this number? [DEC 09] 4.34)What is a type number? 4.35)Give examples of machines handling gases with high pressure rise. 4.36)What do you mean by manometric efficiency and mechanical efficiency of a centrifugal pump? [DEC 07] 4.37)Define pump. 4.38)What is the principle of pump?[DEC 09] 4.39)Give the classification of pumps. 4.40)What is a positive displacement pump? 4.41)Define non - positive displacement pump (or) roto dynamic pump. 4.42)List the types of positive displacement pumps. 4.43)Under what conditions would you suggest use of double-suction pump and a multistage pump?[DEC 10] 4.44)What are roto dynamic pumps? Give examples.[DEC 09] 4.45)List the types of roto dynamic pumps. 4.46)What is a reciprocating pump? 4.47)Why the reciprocating pump is called a positive displacement pump?[MAY 11] 4.48)How are reciprocating pumps classified? [DEC 11] 4.49)Define a single acting reciprocating pump. 4.50)Define a double acting reciprocating pump. 4.51)Brief the working of double acting reciprocating pump.[MAY 11] 4.52)When will you select a reciprocating pump? [DEC 05] 4.53)Draw the relationship between discharge and crank angle for a single acting pump. [DEC 13] 4.54)What is the function of non – return valve in a reciprocating pump?[JUN12] 4.55)Distinguish between centrifugal pump and reciprocating pump.[DEC – 05, 12] 4.56)Mention the significance of 'back leakage'. [DEC 13] 4.57)Define slip of a reciprocating pump. What is negative slip? When does negative slip occur? 4.58)Define slip of reciprocating pump. [MAY 10, DEC 12] 4.59)When does negative slip occur? [DEC 08]

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4.60)What is negative slip in a reciprocating pump? What are the causes for it? [JUN13] 4.61)Define slip of a pump. When does negative slip occur? [DEC 03] 4.62)Define slip and percentage of slip of a reciprocating pump.[DEC – 2008, 2010] 4.63)Define slip, negative slip in reciprocating pump. [JUN 14] 4.64)Define slip and percentage slip. [DEC 11] 4.65)What is the % of slip in reciprocating pump? [JUN– 2012] 4.66)Discuss – slip and volumetric efficiency. [MAY 11] 4.67)Define slip in reciprocating machines. [DEC 11] 4.68)Distinguish between pumps in series and pumps in parallel.[MAY 05] 4.69)What is percentage slip in reciprocating pump?[DEC 06] 4.70)Can actual discharge be greater than theoretical discharge in a reciprocating pump? [DEC 09] 4.71)Which factors determine the maximum speed of reciprocating pump?[DEC 09] 4.72)What factors govern the speed of reciprocating pump?[JUN12] 4.73)Define co-efficient of discharge. 4.74)Brief on acceleration head. [DEC 11] 4.75)Define rotary pump. 4.76)What are rotary pumps? Give examples [MAY 03] 4.77)What is a rotary pump? Give its classification. [MAY 11] 4.78)Define gear pump. 4.79)What is an air vessel? 4.80)What is the function of air vessel?[DEC – 2008, JUN 09, MAY 10] 4.81)What is an air vessel in reciprocating pump? [JUN 06] 4.82)Mention the working principle of an Air-vessel. [MAY 10] 4.83)What is an air vessel? List the objectives that would be fulfilled by the use of air vessels. [DEC 10] 4.84)What is an air vessel? What are its uses? [JUN 12] 4.85)What are the uses of air vessels? [JUN 14] 4.86)What are the advantages of air vessel? [JUN 13] 4.87)State the advantages of fitting air vessels in reciprocating pumps.[JUN 09] 4.88)Define indicator diagram. State its uses. [JUN, DEC 07] 4.89)What is indicator diagram?[JUN 09] 4.90)Draw the ideal indicator diagram. [MAY 10] 4.91)Write down the formula for discharge, work done and power required for a double acting reciprocating pump.

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4.92)What is the main difference between a single acting and double acting reciprocating pump? 4.93)Give the types of rotary pumps. 4.94)What is the formula for work done by a reciprocating pump? 4.95)Give the formula for discharge through a double acting reciprocating pump. 4.96)A single acting reciprocating pump, running at 50rpm. The diameter of piston = 20cm and length = 40cm. Find the theoretical discharge of the pump.[MAY 11] 4.97)A centrifugal pump delivers 20 L/s of water against a head of 850 mm at 900 rpm. Find the specific speed of pump.[MAY 10] 4.98)The following data refer to a centrifugal pump which is designed to run at 1500 rpm. D1 = 100 mm, D2 = 300 mm, B1 = 50 mm, B2 = 20 mm, Vf1= 3 m/s. Find the velocity of flow at outlet. [MAY 10] 4.99)A pump is to discharge 0.82 m3/s at a head of 42 m when running at 300 rpm. What type of pump will be required? [DEC 11]

PART - B 4.100)Draw typical velocity triangles for fluid motion along a series of moving curve vanes and derive Euler’s equation of energy transfer.[DEC 09] 4.101)Explain the construction and working of a centrifugal pump with a neat sketch. 4.102)Explain the operation of centrifugal pump with the help of a neat sketch. Write short notes on different types of casing used in centrifugal pumps.[JUN 07] 4.103)What is the role of volute chamber of a centrifugal pump? Define manometric head. [DEC 09] 4.104)Sketch and briefly describe the volute diffusion type pumps. What function is served by volute chamber in a centrifugal pump?[JUN12] 4.105)Compare the advantages and disadvantages of centrifugal, submersible and jet pumps. [MAY 08] 4.106)What is priming in a centrifugal pump? Why is it necessary?[DEC 05] 4.107)Obtain the expression for work done by impeller of a centrifugal pump on water per second per unit weight of water.[DEC – 2008, JUN 09] 4.108)Describe multi-stage pump with impeller in series and impellers in parallel. [JUN 14] 4.109)Define the manometric efficiency of a centrifugal pump?[DEC 06] 4.110)Define cavitation and discuss its causes, effects and prevention. [MAY 08] 4.111)Define cavitation. What are the effects of cavitation? Give the necessary precaution against cavitation. [JUN – 2009, 2014] 4.112)Define cavitation and explain the various effects of cavitation. [MAY 11] 4.113)Draw the velocity triangle for a centrifugal pump and obtain the expression for the work done.[MAY 11] 4.114)What is specific speed of pump?[MAY – 2004, JUN 09] 4.115)Define speed of a centrifugal pump. How does it differ from that of turbine?

[JUN– 07, 12] 4.116)State the expression for the specific speed of a pump. What is its use? DEC 07, 12

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4.117)What do you understand by characteristics curves of a centrifugal pump? Explain them with neat sketches.[DEC 08] 4.118)Explain in detail about the performance curves for pumps and turbines.[MAY 11] 4.119)Determine the minimum speed for starting a centrifugal pump.[DEC 09] 4.120)Explain briefly the following efficiencies of a centrifugal pump (i) Manometric efficiency (ii) Volumetric efficiency[JUN 14] 4.121)Discuss - characteristics of centrifugal pump at constant speed.[DEC 13] 4.122)Explain the characteristics curves of a centrifugal pump.[DEC09] 4.123)Define specific speed of a centrifugal pump. Derive expression for the same in the terms of head ‘H’, discharge ‘Q’ and speed ‘N’ [JUN 07] 4.124)Enumerate the losses that occur during the operation of the centrifugal pump. [JUN 09] 4.125)Distinguish between roto dynamic pump and positive displacement pump with simple sketch.[MAY 05] 4.126)How rotary pumps are classified. Explain the working principles of any one type of rotary pump with the aid of a neat sketch.[DEC – 2008, JUN– 2012] 4.127)Discuss the working of rotary positive displacement pumps.[MAY 11] 4.128)Discuss in detail about rotary positive displacement pumps.[DEC 11] 4.129)With neat sketches, discuss about the rotary positive displacement pump. DEC 13 4.130)With an example, explain in detail the working principle and construction of rotary pumps with neat diagram. [JUN12] 4.131)Classify pumps. Explain the working of double acting reciprocating pump with a neat diagram.[DEC 09, MAY 10] 4.132)Describe the working and principles of a reciprocating pump.[DEC 05, MAY 11] 4.133)What is a reciprocating pump? Describe the principle and working of a reciprocating pump with a neat sketch. 4.134)Draw a neat sketch of reciprocating pumps. List the components and briefly explain their functions.[DEC 03] 4.135)Describe the principle and working of a reciprocating pump with a neat sketch. [DEC 08] 4.136)Explain the working principle of reciprocating pump with neat sketch.[DEC 08] 4.137)Explain the working principle of a reciprocating pump with neat diagram in detail and state its advantages and disadvantages over centrifugal pump.[JUN 12] 4.138)With a neat sketch explain the working of double acting reciprocating pump with its performance characteristics.[DEC 11] 4.139)Derive an expression for acceleration head developed in a reciprocating pump. 4.140)Explain the working principle of single and double acting reciprocating pumps with neat diagram in detail. Also explain the effects of inertia pressure and friction on the performance of the pump using indicator diagrams with and without air vessel. [DEC 10] 4.141)Sketch and describe the working principle of double acting reciprocating pump with indicator diagram.[DEC 09]

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4.142)Differentiate between single acting and double acting pump.[DEC 09] 4.143)Discuss on the following: Working of double acting pump, indicator diagram, acceleration head, friction head.[DEC 13] 4.144)Define indicator diagram. Prove that the area of the indicator diagram is proportional to the work done by the reciprocating pump. [JUN 14] 4.145)Prove that work done by the pump is proportional to the area of the indicator diagram. [JUN 09] 4.146)Show that the work done by a reciprocating pump is equal to the area of the indicator diagram.[DEC 09, MAY 10] 4.147)Write briefly on the following.

Rotary pumps and their classifications. Indicator diagram for reciprocating pump.[MAY 11]

4.148)Define slip, percentage slip and negative slip of a reciprocating pump.[JUN 09] 4.149)Define: slope, % of slip and negative slop with respect to reciprocating pump. [JUN 09] 4.150)Define % of slip and indicator diagram, with respect to reciprocating pump. [JUN07] 4.151)What is % of slip in reciprocating pump? [MAY 10] 4.152)What is an air vessel? Describe the function of the air vessel for reciprocating pumps. 4.153)What is an air vessel? What are the uses/advantages of fitting air vessel in a reciprocating pump? [JUN 07] 4.154)What is air vessel and write the expression for work done by reciprocating pump fitted with air vessel.[MAY 05] 4.155)What is an air vessel? Derive the expression for the percentage work saved by using an air vessel.[DEC 12] 4.156)What is an air vessel? What are the advantages of fitting air vessel in a reciprocating pump? [DEC 07] 4.157)Calculate the work saved by fitting an air vessel for a double acting single cylinder reciprocating pump. [MAY – 2008, JUN 13] 4.158)Describe the function of the air vessel.[DEC 08, JUN– 2012] 4.159)What are the functions of air vessel in a positive displacement pump?[DEC 09] 4.160)Determine the % of work saved in one cycle when air vessel is provided on the delivery side of a single cylinder single acting reciprocating pump.[JUN 12] 4.161)Explain the working principle of Gear pump with neat sketch.[DEC 08] 4.162)With a neat sketch, explain the working of a gear pump.[DEC 10] 4.163)Explain the construction and working of the following rotary pumps with neat sketches. (a)Gear pump(b)Vane pump [DEC – 2007, JUN 14] 4.164)Explain in detail the working principle and construction of rotary pumps with neat sketch. [JUN 13] 4.165)Explain the working of the following pumps with the help of neat sketches and mention two applications of each. (i) External gear pump(ii) Lobe pump(iii) Vane pump

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(iv) Screw pump. [MAY 10] 4.166)Explain in detail the working of a gear pump with a neat sketch.[MAY, DEC 11] 4.167)Explain the working of vane pump with neat diagram.[JUN12] 4.168)Discuss briefly the working principle of vane pump with a schematic diagram. [DEC 12] 4.169)Explain the working principle of screw pump and gear pump with neat diagram in detail. [DEC 10] 4.170)Draw and explain the indicator diagram for a reciprocating pump including the effect of friction and acceleration. 4.171)Derive an expression for the percentage work saved by using an air vessel with

(i) Single acting and (ii) double acting reciprocating pump. PROBLEMS

4.172)A centrifugal pump is provided at a height of 5m above the sump water level and the outlet of the delivery pipe is 10m above the sump. The vane angle at outlet is 50°. The velocity of flow through the impeller is constant at 1.6m/s. Find : [DEC 08]

The pressure head at inlet to the wheel The pressure head at outlet of the wheel. Assume that the velocity

of water in the pipes is equal to the velocity of flow through the impeller. Ignore losses

4.173)The following observations are made while conducting a performance test on centrifugal pump. Determine the overall efficiency of the pump. Discharge of water is 1.8m3/s. Diameter of suction and delivery pipe are 15cm and 10cm respectively. The suction and delivery gauge readings are 25cm of mercury and 175 kN/m2 respectively. The height of delivery gauge over suction gauge is 0.5m. The output of driving motor is 9.555kW. [MAY 05] 4.174)The head — discharge characteristics of a centrifugal pump is given below. The pump delivers fresh water through a 500 m long, 15 cm diameter pipe line having friction coefficient of f = 0.025. The static lift is 15 m. neglecting minor losses in the pipe flow, find (i) the discharge of the pump under the above conditions (ii) driving power of the pump motor. Assume a pump efficiency of 72%. [DEC 10] 4.175)The internal and external diameters of the impeller of a centrifugal pump are 200mm and 400mm respectively. The pump is running at 1200 rpm. The vane angles of the impeller at inlet and outlet are 20°and 30° respectively. The water enters the impeller radically and the velocity of flow is constant. Determine the work done by the impeller per unit weight of water.[DEC – 08, 12] 4.176)The internal and external diameter of an impeller of a centrifugal pump which is running at 1000 r.p.m, are 200 mm and 400 mm respectively. The discharge through pump is 0.04 m3/s and velocity of flow is constant and equal to 2.0 m/s. The diameters of the suction and delivery pipes are 150mm and 100mm respectively and suction and delivery heads are 6 m (abs.) and 30 m (abs.) of water respectively. If the outlet vane angle is 45º and power required to drive the pump is 16. 186 kW, determine:

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(i) Vane angle of the impeller at inlet, (ii) The overall efficiency of the pump, and (iii) Manometric efficiency of the pump.[JUN 13]

4.177)A centrifugal pump with backward-curved blades has the following measured performance when tested with water at 20°C: Estimate the best efficiency point and the maximum efficiency. Also, estimate the most efficient flow rate, and the resulting head and brake power, if the diameter is doubled and the rotation speed is increased by 50%. [DEC 11] 4.178)The impeller of a centrifugal pump is 300mm outside diameter and 150mm inside diameter. The impeller vane angles are 30° and 25° at the inner and outer peripheries respectively and the speed is 1450rpm. The velocity of the flow through the impeller is constant. Find the work done by the impeller per N of water.[DEC 09] 4.179)A centrifugal pump running at 800rpm is working against a total head of 20.2m. The external diameter of impeller is 480mm and the outlet width is 60mm. If the vane angle at outlet is 40° and manometric efficiency is 70%, determine

Flow velocity at outlet Absolute velocity of water leaving the vane

Angle made by the absolute velocity at outlet with direction of motion Rate of flow through the pump [DEC 09, MAY 10]

4.180)A centrifugal pump running at 1440rpm has an impeller diameter of 0.42m. The backward curved blade outlet angle is 35° to the tangent. The flow velocity at outlet is 10m/s. Determine the static head through which water will be lifted. In case a diffuser reduces the outlet velocity to 40% of the velocity at the impeller outlet, what will increase in the static head? [MAY 11]

4.181)A centrifugal pump running at 1200rpm has a discharge of 13m3/min. The pump has manometric efficiency of 85% and working against a head of 22m. The impeller has an outlet vane angle of 40º. If the velocity of the flow at the outlet is 2.6m/s. Determine the diameter of the impeller and width of the impeller at the outlet. [DEC 12] 4.182)A centrifugal pump is to discharge 0.12 m3/s at a speed of 1400rpm with a head of 30m. The impeller diameter is 275mm, its width at outlet is 50mm. The manometric efficiency is 78%. Calculate the vane angle at the outer periphery of the impeller. [MAY 11] 4.183)A Centrifugal pump impeller runs at 80 rpm and has outlet vane angle of 60°. The velocity of flow is 2.5 m/s throughout and diameter of the impeller at exit is twice that at inlet. If the manometric head is 20 m and the manometric efficiency is 75 percent, determine the diameter of the impeller at the exit and the inlet vane angle. [DEC 11] 4.184)A pump has to supply water which is at 70°C water at 90 m3/min and 1800 rpm. Find the type of pump needed, the power required, and the impeller diameter if the required pressure rise for one stage is 200 kPa; and 1250 kPa.[DEC 11]

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4.185)A centrifugal pump with an impeller diameter of 0.4 m runs at 1450 rpm. The angle at outlet of the backward curved vane is 25º with tangent. The flow velocity remains constant at 3 m/s. If the manometric efficiency is 84% determine the fraction of the kinetic energy at outlet recovered as static head.[DEC 13] 4.186)The impeller of a centrifugal pump is 300mm in diameter and having a width of 50mm at the periphery. It has blades whose tip angles are inclined backwards at 60° from the radius. The pump delivers 17m3/min of water and the impeller rotates at 1000rpm. Assuming that the pump is designed to admit liquid radially, calculate

Speed and direction of water as it leaves impeller Torque exerted by the impeller on water Shaft power required Lift of the pump Assume the mechanical efficiency = 95%

and the hydraulic efficiency = 75% [JUN – 07, 12] 4.187)A centrifugal pump discharges 2000 l/s of water per second developing a head of 20m when running at 300rpm. The impeller diameter at the outlet ant the outflow velocity is 1.5m and 3m/s respectively. It vanes are set back at an angle of 30° at the outlet, determine

Manometric efficiency & Power required by the pump If inner diameter is 750mm, find the minimum speed to start the pump. [JUN 12] 4.188)The impeller of a centrifugal pump has an external diameter of 450mm and internal diameter of 200mm and it runs at 1440rpm. Assuming a constant radial flow through the impeller at 2.5m/s and the vanes at exit are set back at an angle of 25°. Determine

Inlet vane angle The angle, absolute velocity of water at exit makes with the

tangent and The work done per N of water. [DEC 06]

4.189)A centrifugal pump has 30 cm and 60 cm diameters at inlet and outlet. The inlet and outlet vane angles are 30° and 45° respectively. Water enters at a velocity of 2.5 m/s radially. Find the speed of impeller in rpm and the power of the pump if the flow is 0.2 m3/s.[MAY 08] 4.190)A centrifugal pump delivers water against a net head of 14.5 meters and a design speed of1000 rpm. The vanes are curved back to an angle of 30° with the periphery. The impeller diameter is 300 mm and outlet width 50 mm. Determine the discharge of the pump if the manometric efficiency is 95%. [DEC07] 4.191)A centrifugal pump with 1.2m diameter runs at 200rpm and discharge 1880 litres/s, against an average lift of 6m. The angle which the vanes make at exit with the tangent to the impeller is 26° and the radial velocity of the flow is 2.5m/s. Find the manometric efficiency and at least speed to start the pump against the head of 6m. Assume the inner diameter of the impeller as 0.6m. [JUN 09] 4.192)A single stage centrifugal pump with impeller diameter of 30cm rotates at

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2000rpm and lifts 3m3 of water per second to a height of 30m with an efficiency of 75%. Find the number of stages and diameter of each impeller of a similar multistage pump to lift 5m3 of water per second to a height of 300m when rotating at 1500rpm. [JUN 09] 4.193)A centrifugal pump having an outer diameter equal to two times the inner diameter and running at 1000 rpm. Works against a total head of 40m. The velocity of flow through the impeller is constant and equal to 2.5m/sec. The vanes are set back at an angle of 40° at outlet. If the outer diameter of the impeller is 500mm and width at outlet is 50mm, determine the

i) Vane angle at inlet ii) Manometric efficiency iii) Work done by impeller on water per second.

4.194)The outer diameter of an impeller of a centrifugal pump is 400mm and outlet width is 50mm. The pump is running at 800rpm and working against a total head of 15m. The vanes angle at outlet is 40° and the manometric efficiency is 75%. Determine the velocity of flow at inlet, velocity of water leaving the vane, angle made by the absolute velocity at outlet with direction of motion at outlet, and the discharge. [DEC – 2007, 2012] 4.195)The centrifugal pump has the following characteristic. Outer diameter of impeller = 800mm; width of the impeller vane at outlet = 100mm; angle of the impeller vanes at outlet = 40°. The impeller runs at 550 rpm and delivers 0.98 m3/s under an effective head of 35m. A 500 kW motor is used to drive the pump. Determine the manometric, mechanical and overall efficiencies of the pump. Assume waters enter impeller vanes radially at inlet. [MAY – 2003, 2010] 4.196)A centrifugal pump delivers water against a net head of 14.5m and design speed of 1000rpm. The vanes are curved back angle of 30° with the periphery. The impeller diameter is 300mm and the outlet width 50mm. Determine the discharge of the pump if manometric efficiency is 95%. [DEC 07] 4.197)A centrifugal pump, in which water enters radially, delivers water to a head of 165m. The impeller has a diameter of 360mm and width 180mm at inlet and the corresponding dimensions at the outlet are 720mm and 90mm respectively. Its rotational speed is 1200 rpm. The blades are curved backward at 30° to the tangent at exit and discharge is 0.389 m3/s. Determine [JUN 07]

Theoretical head developed Manometric efficiency Pressure rise across the impeller assuming losses equal to 12% of

velocity head at exit. Pressure rise and the loss of head in the volute casing The vane angle at inlet and Power required to drive the pump assuming an overall efficiency

of 70%. What would be the corresponding mechanical efficiency?

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4.198)Compute the overall efficiency of a centrifugal pump from the following test data. Suction gauge reading = 27.5kPa(vaccuum) and delivery gauge reading = 152(gauge) height of the delivery gauge over suction gauge is 0.4m, discharge is 2100mm. Diameter of the suction pipe is 15cm and diameter of delivery pipe is 10cm. the motor power = 12MHP and fluid water.[DEC 09] 4.199)A centrifugal pump id to discharge 0.118m3/s at a speed of 1450rpm against a head of 25m. The impeller diameter is 25cm, its width at outlet is 5cm and manometric efficiency is 75%. Determine the vane angle at the outer periphery of the impeller and draw its velocity triangle. [MAY 11] 4.200)A centrifugal pump delivers 400 litres/s of water to a height of 20m through a pipe diameter 15cm and length 100m. The pump has an overall efficiency of 70% and the friction coefficient is 0.15. Determine the power required to drive the pump. [DEC 10] 4.201)A single acting reciprocating pump, running at 50rpm, delivers 0.01m3/sec of water. The diameter of the piston is 200mm and stroke length 400mm. Determine the 1. Theoretical discharge of the pump 2. Co-efficient of discharge 3. Slip and the percentage slip of the pump [DEC – 07, 08, JUN– 12] 4.202)For a single acting reciprocating pump, piston diameter is 150 mm, stroke length is 300 mm, and rotational speed is 50 r.p.m. The pump is required to lift water to a height of 18 m. Determine the theoretical discharge. If the actual discharge is 4.0 lit/sec, and the mechanical efficiency is 80% determine the volumetric efficiency, slip, theoretical power and the actual power required. [DEC 10] 4.203)A single – acting reciprocating pump has a plunger diameter of 250mm and stroke of 150mm. It is driven at 60rpm and undergoes SHM. The length and diameter of the delivery pipe are 60m and 100mm respectively. Determine the power saved in overcoming the friction in the delivery pipe, due to fitting of an air vessel on the delivery side of the pump. Assume the friction factor f = 0.01 the pipe friction formula hf=(flv2/2gd)[DEC 07]

4.204)A single acting reciprocating pump is to raise a liquid of density 1200kg/m3 through a vertical height of 11.5m, from 2.5m below pump axis to 9m above it. The plunger which moves in SHM, has diameter 125mm and stroke 225mm. The suction and delivery side pipes are 75mm diameter and 3.5 and 1.5m long, respectively. There is a large air vessel fitted on the delivery pipe near to the pump axis. But there is no air vessel on the suction pipe. If separation takes place at 8.829 N/cm2 below atmospheric pressure, find the maximum speed at which the pump can run without separation taking place and the power required to drive the pump. Assume there is no slip in the pump and f = 0.08 the pipe friction formula hf=(flv2/2gd) [DEC 07] 4.205)A single acting reciprocating pump has a plunger of diameter 30 cm and stroke of 20 cm. If the speed of the pumps is 30 rpm and it delivers to6.5 lit/s of water, find the coefficient of discharge and the percentage slip of the pump. [MAY 11]

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4.206)The piston area of a single acting reciprocating pump 0.15 m2 and stroke is 30 cm. The water is lifted through a total head of 15 m. The area of delivery pipe is 0.03 m2. If the pump is running at 50rpm, find the percentage slip, coefficient of discharge and the power required to derive the pump. The actual discharge is 350 litres per second. Take mechanical efficiency is 0.85.[DEC 11] 4.207)A single acting reciprocating pump has a diameter (piston) of 150mm and stroke length 350 mm. The center of the pump is 3.5 m above the water surface in the sump and 22 m below the delivery water level. Both the suction and delivery pipes have the same diameter of 100 mm and are 5 m and 30 m long respectively. If the pump is working at 30 rpm determine the pressure heads on the piston at the beginning, middle and end of both suction and delivery strokes. [DEC 11] 4.208)Calculate the rate of flow in and out of the air vessel on the delivery side in a single acting reciprocating pump of 220 mm bore and 330 mm stroke running at 50 rpm. Also find the angle of crank rotation at which there is no flow into or out of the air vessel. [DEC 11] 4.209)In a single acting reciprocating pump the bore and stroke are 100 and 150 mm. respectively. The static head requirements are 4 m suction and 18 m delivery. If the pressure at the end of delivery is atmospheric calculate the operating speed. The diameter of the delivery pipe is 75 mm and the length of the delivery pipe is 24 m. Determine the acceleration head at θ = 33 from the start of delivery.[DEC 11] 4.210)A double - acting reciprocating pump, running at 40rpm is discharging 1m3 of water per minute. The pump has a stroke of 400mm. The diameter of the piston is 200mm. The delivery and suction heads are 20m and 5m respectively. Find the slip of the pump and the power required to drive the pump. 4.211)The cylinder bore diameter of a single acting reciprocating pump is150mm and its stroke length is 300mm. The pump runs at 50 rpm and lifts water through a height of 25m. The delivery pipe is 22m long and 100mm in diameter. Find the theoretical discharge and the theoretical power required to run the pump. If the actual discharge is 4.2 litres/s. Find the percentage of slip.[MAY 04, DEC 05, 2012] 4.212)The diameter and stroke of a single acting reciprocating pump are 120 mm and 300 mm respectively. The water is lifted by a pump through a total head of 25 m. The diameter and length of delivery pipe are 100 mm and 20 m. respectively. Find out:

(i) Theoretical discharge and theoretical power required to run the pump if its speed is60 rpm.

(ii) Percentage slip, if the actual discharge is 2.95 1/s and (iii) The acceleration head at the beginning and middle of the

delivery stroke.[MAY 10] 4.213)The length and diameter of a suction pipe of a single acting reciprocating pump are 5 m and 10 cm respectively. The pump has a plunger of diameter 150 mm and a stroke length of 300 mm. The center of the pump is 4 m above the water surface in the sump. The atmospheric pressure head is 10.3m of water and the pump runs at 40 rpm.

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Determine the i) Pressure head due to acceleration at the beginning of the suction stroke. ii) Maximum pressure head due to acceleration. iii) Pressure head in the cylinder at the beginning and at the end of the

stroke. 4.214)Consider a double acting reciprocating pump running at 40rpm. The pump delivers 1m3/min of water. The piston diameter is 20cm and the stroke length is 40cm. The delivery and the suctions heads are 20m and 5m respectively. Calculate the % slip and the power required to drive the pump. [DEC 10] 4.215)The diameter and the stroke of a single acting reciprocating pump are 200mm and 400mm respectively, the pump runs at 60 rpm and lifts 12 litres of water per second through a height of 25m. The delivery pipe is 20m long and 150mm in diameter. Find (i) theoretical power required to run the pump (ii) % of slip and (iii) acceleration head at the beginning and middle of the delivery stroke.[DEC 03] 4.216)The diameter and stroke length of a single acting reciprocating pump are 75 mm and 150 mm respectively. Supply of water to the pump is from a sump 3 m below the pump through a pipe of 5 m long and 40 mm in diameter. The pump delivers water to a tank located at 12 m above the pump through a pipe 30 mm in diameter and 15 m long. Assuming that a separation of flow occurs at 75 kN/m2 (below the atmospheric pressure), find the maximum speed at which the pump MAY be operated without any separation.[JUN 07] 4.217)The cylinder of a single- acting reciprocating pump is 15 cm in diameter and 30 cm in stroke. The pump is running at 30 r.p.m. and discharge water to a height of 12 m. The diameter and length of the delivery pipe are 10 cm and 30 m respectively. If a large air vessel is fitted in the delivery pipe at a distance of 2 m from the centre of the pump, find the pressure head in the cylinder.

(i) At the beginning of the delivery stroke, and (ii)In the middle of the delivery stroke. Take f = 0.01.[JUN 13]

4.218)A double acting pump with 35 cm bore and 40 cm stroke runs at 60 strokes per minute. The suction pipe is 10m long and delivery pipe is 200m long. The diameter of the delivery pipe is 15 cm. The pump is situated at a height of 2.5 m above the sump; the outlet of the delivery pipe is 70 m above the pump. Calculate the diameter of the suction pipe for the condition that separation is avoided. Assume separation to occur at an absolute pressure head is 2.5m of water. Find the Horsepower required to drive the pump neglecting all losses other than friction in the pipes assuming friction factor f as 0.02. [DEC 08] 4.219)A double acting reciprocating pump is running at 30rpm. Its bore and stroke are 250mm and 400mm respectively. The pump lift water from sump 3.8m below and delivers it to a tank located at 65m above the axis of the pump. The lengths of suction and delivery pipes are 6m and 150m respectively. The diameter of the delivery pipe is 100mm. if an air vessel of adequate capacity has been fitted on the delivery side of

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the pump, determine The minimum diameter of the suction pipe to prevent separation

of flow, assuming the minimum head to prevent occurrence of separation is 2.5m

4.220)The maximum gross head against which the pump has to work and the corresponding power of motor. Assume the mechanical efficiency = 78% and slip = 1.5%; Hatm = 10m; F=0.012. [JUN 07] 4.221)The plunger diameter and the stroke length of a single acting reciprocating pump are 300mm and 500mm respectively. The speed of the pumps is 50rpm. The diameter and length of the delivery pipe are 150mm and 55m respectively. If the pump is equipped with an air vessel at delivery side at the center line of the pump, find the power saved in overcoming friction in delivery pipe. Assume Darcy’s friction factor as 0.01.[JUN 09] [JUN 14] 4.222)The diameter and length of a single acting reciprocating pump are 100mm and 200mm respectively. The pump is used to deliver water to the tank 14m above the pump through a pipe of 30mm in diameter and 18m long by taking its supply from the sump am below the pump, through a pipe 40mm in diameter and 6m long. If separation occurs at 78.48kN/m2, below the atmospheric pressure find the maximum speed at which the pump can be operated without separation. Assume 1 atm pressure = 10.3m of water column and the plunger undergoes simple harmonic motion. [JUN 09] 4.223)Determine the maximum operating speed in rpm and the maximum capacity in LPs of a single acting reciprocating pump with the following details. Plunger diameter = 25cm, stroke = 50cm, suction pipe diameter = 15cm, length = 9cm, delivery pipe diameter = 10cm, length = 36cm, static suction head = 3m, static delivery head = 20m, atmospheric pressure = 76cm of mercury, vapour pressure of water = 25kPa. [DEC 09] 4.224)A reciprocating pump handling water with a bore of 110mm and stroke of 205mm runs at 38rpm. The delivery pipe is of 90mm diameter and 30m long. An air vessel of sufficient volume is added at a distance of 2.5m from the pump. Determine the acceleration head with and without air vessel. [MAY 11] 4.225)A single cylinder double acting reciprocating pump has a piston diameter of 300mm and stroke length of 400mm. When the pump runs at 45rpm, it discharges 0.039m3/s under a total head of 15m. What will be the volumetric efficiency, work done per second and power required if the mechanical efficiency of the pump is 75%. [JUN12] 4.226)The indicator diagram of a single acting reciprocating pump gives effective delivery head of 5m and 23m with crank at inner and outer dead center respectively. What is the static delivery head of reciprocating pump? [MAY 05]

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UNIT – V – TURBINES PART - A

5.1)Define turbo machines. 5.2)Define turbine. 5.3)Classify fluid machines. [MAY 10] 5.4)Give the classification of turbines. 5.5)How are hydraulic turbines classified [JUN 09, 2014, DEC 09 MAY 11] 5.6)What are high head turbines? Give example. [DEC 09] 5.7)State the principles on which turbo-machines are based. [DEC 10] 5.8)Explain specific speed. [DEC 05] 5.9)Define specific speed. [DEC 09] 5.10)Define specific speed of a turbine. [DEC 03, 08, 09, JUN–07, 09, MAY –10, 11] 5.11)Define specific speed of a turbine. What is its usefulness?[DEC 07] 5.12)How is specific speed of a turbine defined? [JUN 06] 5.13)What is meant by specific speed of a turbine? [MAY 10] 5.14)Write the equation for specific speed for pumps and also for turbine.[DEC 12] 5.15)What is hydraulic turbine? [JUN 06] 5.16)Classify turbines according to flow. [DEC 05] 5.17)Define impulse turbine and give examples. 5.18)Explain the working of impulse turbine. [MAY 11] 5.19)Define reaction turbine and give examples. 5.20)What is reaction turbine? Give examples [MAY 03] 5.21)Differentiate b/w reaction turbine and impulse turbine.[DEC03,MAY08,JUN 12] 5.22)What is a ‘breaking jet’ in Pelton wheel/turbine?[JUN 07, DEC – 2007, 2012] 5.23)Draw velocity triangle diagram for Pelton wheel turbine.[DEC08] 5.24)Define tangential flow turbine. 5.25)Define radial flow - turbine. 5.26)Define axial flow turbine. 5.27)Define mixed flow turbine. 5.28)Define the flow ratio of reaction radial flow turbine. [DEC 12] 5.29)Draw a sketch of a Francis turbine and name its components.[MAY 05] 5.30)List the main parts of Kaplan turbine.[DEC 12] 5.31)What is draft tube? [DEC 12] 5.32)What is a draft tube? Explain why it is necessary in reaction turbine. 5.33)What is draft tube? In which type of turbine is mostly used?[DEC 03] 5.34)Write the function of draft tube in turbine outlet?[MAY 05, 2008, DEC 11] 5.35)What is the function of draft tube?[JUN– 2007, DEC 09] 5.36)What are the different types of draft tubes? [DEC 09] 5.37)Why does a Pelton wheel not possess any draft tube? [JUN12] 5.38)Mention the importance of Euler turbine equation. [DEC 11] 5.39)What are the different efficiencies of turbine to determine the characteristics of turbine? [JUN– 2012]

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5.40)Define hydraulic efficiency of turbine 5.41)Define hydraulic efficiency and jet ratio of a Pelton wheel. [DEC 10] 5.42)Define hydraulic e f f i c i e n c y and a x i a l t h ru s t o f a r o t o -dynamic h y d r a u l i c machine. [JUN 13] 5.43)What is meant by hydraulic efficiency of turbine?[DEC – 2012, 2013] 5.44)Define hydraulic efficiency and overall efficiency of a turbine.[DEC 12] 5.45)What are the different efficiencies of turbine to determine the characteristics of turbine? [DEC 06] 5.46)Define overall efficiency and plant efficiency of turbines.[JUN– 2007, 2012] 5.47)Draw the characteristics curves of a turbine with head variation.[MAY 05] 5.48)What is the difference between a turbine and a pump?[DEC – 2010, JUN 12] 5.49)Differentiate between pumps and turbines.[JUN, DEC – 2007, 2008] 5.50)A shaft transmits 150 Kw at 600 rpm. What is the torque in N.m?[MAY 11] 5.51)The mean velocity of the buckets of the Pelton wheel is 10 m/s. The jet supplies water at 0.7 m3/s at a head of 30 m. The jet is deflected through an angle of 160° by the bucket. Find the hydraulic efficiency. Take CV = 0.98.[MAY 10] 5.52)A water turbine has a velocity of 8.5m/s at the entrance of draft tube and velocity of 2.2m/s at exit. The frictional loss is 0.15m and the tail race water is 4m below the entrance of draft tube. Calculate the pressure head at entrance.[MAY 11]

PART – B 5.53)Derive the general equation of turbo machines and draw the inlet and outlet triangles. [MAY 11] 5.54)How will you classify the turbines? [DEC 08] 5.55)Describe briefly the function of the various main components of a Pelton wheel turbine with neat sketches. 5.56)Describe briefly the functions of various components of Pelton turbine with neat sketches. [DEC 08] 5.57)Explain the component parts and working of a Pelton wheel turbine.[MAY 10] 5.58)Define and derive an expression for specific speed of a turbine. 5.59)Explain the terms unit power, unit speed and unit discharge with reference to a turbine. 5.60)Explain the hydraulic efficiency of a turbine.[DEC 09] 5.61)Sketch the velocity triangles at inlet and outlet of a Pelton wheel. 5.62)What is breaking jet in Pelton wheel turbine?[MAY – 2004, DEC05, JUN– 2012] 5.63)Differentiate Pelton wheel turbine with Francis turbine.[MAY 05] 5.64)Distinguish between reaction turbine and impulse turbine.[JUN 13] 5.65)Give the comparison between impulse and reaction turbine.[DEC 05] 5.66)With the help of neat diagram explain the construction and working of a Pelton wheel turbine.[DEC 05] 5.67)With a neat sketch, explain the working of a Pelton wheel. [MAY 08] 5.68) with a neat sketch, explain the working of a Pelton wheel. Also obtain the expression of the work done.[DEC 12]

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5.68)Obtain an expression for power developed in a reaction turbine.[DEC 11] 5.69)What is the condition for hydraulic efficiency of a Pelton wheel to be maximum? [DEC 05] 5.70)Explain the construction and working of the following turbines with neat sketches. (i) Pelton wheel turbine (ii) Francis turbine(iii) Kaplan turbine 5.71)Compare radial flow and axial flow turbo machines. 5.72)Draw the inlet and outlet velocity triangles for an inward flow reaction turbine indicating the various components.[DEC 09] 5.73)Derive an expression for the maximum hydraulic efficiency of an impulse turbine. 5.74)Obtain an expression for the work done per second by water on the runner of a Pelton wheel. Hence derive an expression for maximum efficiency of the Pelton wheel giving the relationship between the jet speed and bucket speed.[DEC 07] 5.75)Obtain the expression for the work done per second by water on the runner of a Pelton wheel and draw inlet and outlet velocity triangles for a Pelton turbine and indicates the direction of various velocities. [JUN 09] 5.76)Derive the velocity triangle for Pelton wheel and obtain the expression for the work done. [DEC 10, MAY 11] 5.77)Sketch the velocity triangles at inlet and outlet of Pelton wheel.[DEC 06] 5.78)Derive the expression for efficiency and work done for a Pelton wheel and draw the velocity triangles.[JUN12] 5.79)Explain how the net head on the reaction turbine is increased with the use of draft tube. [MAY 08] 5.80)Derive Euler’s equation of motion for turbines and obtain the components of energy transfer with a construction of velocity triangles. [JUN 12] 5.81)An inward flow reaction turbine has inlet and outlet vane angles φ and Ф are both equal to 90°. If H = head of the machine, α = guide vane angle and C = ratio of velocity of flow at outlet and inlet, show that the peripheral velocity and

hydraulic efficiency are given by [DEC 09] 5.82)Show that the hydraulic efficiency for a Francis turbine having velocity flow through runner as constant given by relation.[MAY 11] 5.83)An inward flow reaction turbine discharges radially and the velocity of flow is

constant, show that the hydraulic efficiency can be expressed byWhere α and θ are the guide and vane angles at inlet.[JUN 12] 5.84)Write a short note on Governing of Turbines. [DEC 08] 5.85)Classify hydraulic machines and give one example for each.[DEC 08] 5.86)Explain the working principle of Kaplan turbine and derive the working

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proportion of its design.[DEC 08] 5.87)Draw a neat sketch of Kaplan turbine, name the parts and briefly explain the working. [JUN 07] 5.88)Draw a schematic diagram of a Kaplan turbine and explain its construction and Working. [JUN 14] 5.89)Explain with help of a diagram, the essential features of Kaplan turbine.[DEC 09] 5.90)Draw a schematic diagram of a Kaplan turbine and explain briefly its construction and working. Obtain an expression for work done by the runner. [DEC 11] 5.91)What is function draft tube in Francis turbine?[MAY – 03, 2010] 5.92)Derive an expression for the efficiency of draft tube.[DEC 06] 5.93)Derive an expression for specific speed. What is the significance of specific speed of turbine?[JUN 09] 5.94)How is a specific speed of the turbine, defined? [JUN 09] 5.95)Write a note on performance curves of turbine.[MAY 10] 5.96)Show that the overall efficiency of a hydraulic turbine is the product of volumetric, hydraulic and mechanical efficiencies.[JUN 07] 5.97)Define: Hydraulic and overall efficiency with respect to turbines.[DEC 07] 5.98)Explain the different types of the efficiency of a turbine.[DEC 08] 5.99)Explain the load efficiency characteristics of hydraulic turbines with a diagram. [DEC 13] 5.100)A Pelton wheel supplied water from reservoir under a gross head of 112m and the friction losses in pen stock amounts to 20m of head. The water from pen stock is discharged through a single nozzle of diameter of 100mm at the rate of 0.30m3/s. Mechanical losses due to friction amounts to 4.3kW of power and the shaft power available is 208kW. Determine velocity of jet, water power at inlet to runner, power losses in nozzles, power lost in runner due to hydraulic resistance.[JUN 07] 5.101)A Pelton wheel is having a mean bucket diameter of 1 m and is running at 1000 rpm. The net head on the Pelton wheel is 700 m. If the side clearance angle is 15°and the discharge through the nozzle is 0.1m3/sec, find the i) power available at the nozzle and ii) hydraulic efficiency of the turbine. Take CV=1.[DEC07] 5.102)A Pelton turbine is required to develop 9000 kW when working under a head of 300m the impeller may rotate at 500 rpm. Assuming a jet ratio of 10 and overall efficiency of 85% calculate [DEC 03] 1. Quantity of water required 2. Diameter of the wheel 3. Number of jets 4. Number and size of the bucket vanes on the runner 5.103)The nozzle of a Pelton wheel gives a jet of 9cm diameter and velocity 75m/s. Coefficient of velocity is 0.978. The pitch circle diameter is 1.5m and the deflection angle of the buckets is 170°. The wheel velocity is 0.46 times the jet velocity. Estimate the speed of the Pelton wheel turbine in rpm, theoretical power developed and also the efficiency of the turbine.[MAY 05, DEC 09]

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5.104)A Pelton turbine having 1.6m bucket diameter develops a power of 3600kW at 400rpm, under a net head of 275m. If the overall efficiency is 88%, and the coefficient of velocity is 0.97, find speed ratio, discharge, diameter of the nozzle and specific speed. [JUN 07] 5.105)A Pelton wheel has a mean bucket speed of 12m/s and supplied with water at the rate of 0.7m3/s under a head of 300m. If the buckets deflect the jet through an angle of 160° find the power developed and hydraulic efficiency of the turbine.[MAY 08] 5.106)A Pelton turbine is to produce 18MW under a head of 450 m when running at 480 rpm. If D/d ratio is 10, determine the number of jets required.[DEC 11] 5.107)Consider an impulse wheel with a pitch diameter of 2.75m and a bucket angle of 170°. If the velocity is 58m/s, the jet diameter is 100mm, and the rotational speed is 320rpm, find the force on the buckets, the torque on the runner, and the power transferred to the runner. Assume v2 = 0.9v1.[MAY 11] 5.108)A gas turbine operates between 1000k and 650 k temperature limits taking in air 20 kg/s at 125 m/s and discharging at 300 m3/s. Estimate the power developed by the turbine. Given Cp=995 J / Kg.K.[MAY 11] 5.109)A reaction turbine at 450rpm, head 120m, diameter at inlet 120cm flow area 0.4m2 has angles made by absolute and relative velocities at inlet 20° and 60° respectively. Find volume flow rate, H.P and efficiency.[DEC 09] 5.110)An inward flow reaction turbine has internal and external dia. as 0.85m and 1m respectively. The hydraulic efficiency of turbine is 0.92 under a head of 60m. The velocity of flow at outlet is 3m/s and discharge at outlet is radial. The vane angle at the outlet is 18° and width of the wheel is 75mm. Calculate the guide blade angle, turbine speed, vane angle at inlet and power developed by the turbine. [MAY 11] 5.111)An inward flow reaction turbine has external and internal diameters as 0.9m and 0.45m respectively. The turbine is running at 200 rpm and width of the turbine at inlet is 200mm. The velocity of flow through the runner is constant and is equal to 1.8m/sec. The guide blades make an angle of 10° to the tangent of the wheel and the discharge at the outlet of the turbine is radial. Determine the 1. Absolute velocity of water at inlet of runner 2. Velocity of whirl at inlet 3. Relative velocity at inlet 4. Runner blade angles 5. Width of the runner at outlet 6. Mass of water flowing through the runner per second 7. Head at the inlet of the turbine 8. Power developed and hydraulic efficiency of the turbine. 5.112)An inward flow reaction turbine having an overall efficiency of 80% is required to deliver 136 kW. The head H is 16 m and the peripheral velocity is 3.3 √H. The radial velocity of flow at inlet is 1.1√H. The runner rotates at 120 rpm. The hydraulic losses in the turbine are 15% of the flow available energy. Determine (i) diameter of the runner, (ii) guide vane angle, (iii) the runner blade angle at inlet and (iv) the discharge through the turbine.[DEC 10] 5.113)In an outward flow reaction turbine, the internal and external diameters are 2m and 2.7m respectively. The turbine speed is 275rpm and the water flow rate is

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5.5m3/s. The width of the runner is constant at the inlet and outlet and equal to 250mm. The head acting on the turbine is 160m. The vanes have negligible thickness and the discharge at the outlet is radial. Determine the vane angles and velocity of the flow at inlet and outlet.[DEC 12] 5.114)In a hydroelectric station, water is available at the rate of 175m3/s under head of 18m. The turbine run at a speed of 150 rpm, with overall efficiency of 82%. Find the number of turbines required, if they have the maximum specific speed of 460. [DEC 05] 5.115)A radial flow impeller has a diameter 25 cm and width 7.5 cm at exit. It delivers 120 liters of water per second against a head of 24 m at 1440 rpm. Assuming the vanes block the flow area by 5% and hydraulic efficiency 0.8, estimate the vane angle at exit. Also calculate the torque exerted on the driving shaft in the mechanical efficiency is 95%[DEC 03] 5.116)A 50m/s velocity jet of water strikes without shock, a series of vanes moving at 15m/s. The jet is inclined at an angle of 20° to the direction of motion of vanes. The relative velocity of jet at outlet is 0.9 times of the values at inlet and the absolute velocity of water exit is to be normal to the motion of vanes. Determine the vane angle at entrance and exit. Also determine work done on vanes per second N of water supplied by the jet.[MAY 05] 5.117)In an inward radial flow turbine, water enters at an angle of 22° to the wheel tangent to the outer rim and leaves at 3 m/s. The flow velocity is constant through the runner. The inner and outer diameters are 300 mm and 600 mm respectively. The speed of the runner is 300 rpm. The discharge through the runner is radial. Find the (i) Inlet and outlet blade angles. (ii) Taking inlet width as 150 mm and neglecting the thickness of the blades, find the power developed by the turbine.[MAY 10] 5.118)The velocity of the whirl at the inlet to the runner of an inward flow reaction turbine is 3.15√H m/s and the velocity of flow at inlet is 1.05√H m/s. The velocity of whirl at exist is 0.22√H m/s in the same direction as at inlet and the flow at exist is 0.83√H m/s, where H is head of water 30m. The inner diameter of the runner is 0.6 times the outer diameter. Assuming hydraulic efficiency of 80%. Compute angles of the runner vanes at inlet and exist.[MAY – 2003, 2010] 5.119)Design a Francis Turbine runner with the following data: Net head = 70m speed N = 800 rpm. Output power 400 Kw Hydraulic efficiency = 95% Overall efficiency = 85% Flow ratio = 0.2 Breadth ratio = 0.1 Inner diameter is 1/3 outer diameter. Assume 6% circumferential area of the runner to be occupied by the thickness of the vanes. The flow is radial at exit and remains constant throughout. [DEC 08] 5.120)The following data is given for a Francis Turbine Net head = 60m speed N = 700 rpm. Shaft power 294.3 Kw Hydraulic efficiency = 93% Overall efficiency = 84% Flow ratio = 0.2 Breadth ratio = 0.1 Inner diameter is 1/2 outer diameter. Assume 5% circumferential area of the runner to be occupied by the thickness of the

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vanes. Velocity of flow is constant at inlet and outlet and discharge is radial outlet. Determine1. Guide blade angle 2. Runner vane angle at inlet and outlet 3. Diameter of the runner at inlet and outlet 4. Width of the wheel at inlet [DEC 12] 5.121)The inner and outer diameters of an inward flow reaction turbine are 50 cm and 100 cm respectively. The vanes are radial at inlet and discharge is also radial. The inlet guide vanes angle is 10°. Assuming the velocity of flow as constant and equal to 3 m/s, find the speed of the runner and the vane angle at the outlet.[MAY 08] 5.134) A reaction turbine works at 450rpm under a head of 120metres. Its diameter at inlet is 120cm and the flow area is 0.4m2. The angles made by absolute and relative velocities at inlet are 20° and 60° respectively with the tangential velocity. Determine the 1. Volume flow rate 2. Power developed 3. Hydraulic efficiency.[DEC 07] 5.122)A turbine is to operate under a head of 25m at 200rpm. The discharge is 9cumec. If the efficiency is 90%, determine the

(i) Specific speed of the turbine (ii) Power generated (iii) Type of turbine 5.123)A Francis turbine with overall efficiency of 75% is required to produce 149.26kN. It is working against a head of 7.62m. The peripheral velocity is 0.26√ (2gH) and the radial velocity of flow at inlet is 0.96√ (2gH). The wheel runs at 150rpm and the hydraulic losses in the turbine account for 22% of the available energy. Assume radial discharge; determine the guide blade angle, the wheel vane angle at inlet, diameter of the wheel at inlet and width of the wheel at inlet.[JUN09, 13] 5.124)A Francis turbine with overall efficiency of 76% and hydraulic efficiency of 80% is required to produce 150kW. It is working against a head of 8m. The peripheral velocity is 0.25√(2gH) and the radial velocity of flow at inlet is 0.95√(2gH). The wheel runs at 150rpm. Assume radial discharge; determine the guide blade angle, the wheel vane angle at inlet, diameter of the wheel at inlet and width of the wheel at inlet. [DEC – 2009, MAY 10] 5.125)A dam on a river is being sited for a hydraulic turbine. The flow rate is 1600 m3/h, the available head is 25 m, and the turbine speed is to be 460 rpm. Discuss the estimated turbine size and feasibility for a Francis turbine; and a Pelton wheel. [DEC 11] 5.126)A turbine is to operate under a head of 25m at 200rpm. The discharge is 9 cumec. If the efficiency is 90%, determine the performance of the turbine under a head of 20 meters. [DEC 07] 5.127)A reaction turbine works at 450 rpm under a head of 120 m. Its diameter at inlet is 120 cm and the flow area is 0.4 m2. The angles made by the absolute and relative velocity at inlet are 20° and 60° respectively, with the tangential velocity. Determine the volume flow rate, the power developed and the hydraulic efficiency. [DEC 07]

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5.128)Calculate the diameter and speed of the runner of a Kaplan turbine developing6000 kW under an effective head of 5 m. Overall efficiency of the turbine is 90% and the diameter of the boss is 0.4 times the external diameter of the runner. The turbine speed ratio is 2.0. And flow ratio is 0.6. [DEC 06] 5.129)A Kaplan turbine runner is to be designed to develop 7357.5kW shaft power. The net available head is 5.50m. Assume that the speed ratio is 2.09 and flow ratio is 0.68, and the overall efficiency is 60%. The diameter of the boss is 1/3rd. Of the diameter of the runner, its specific speed.[JUN 09] 5.130)A Kaplan turbine runner is to be designed to develop 7360kW. The net available head is 5.5m. Assuming the speed ratio is 2.09 and the flow ratio is 0.68 and the overall efficiency is 60%. The diameter of the boss is one third of the diameter of the runner. Find the diameter of the runner, its speed and its specific speed.[DEC 09] 5.131)A Kaplan turbine working under a head of 20 m develops 15 MV brake power. The hub diameter and runner diameter of the turbine are 1.5 m and 4 m respectively. The guide blade angle at the inlet is 30°. The discharge is radial. Find the runner vane angles and turbine speed. [MAY 10, DEC 11] 5.132)A Kaplan turbine is to be designed to develop 9100kW. The net available head is 5.6m/ If the speed ratio is 0.68, overall efficiency 86% and the diameter of the boss is 1/3 the diameter of the runner. Find the diameter of the runner, its speed and specific speed of turbine. [MAY 11] 5.133)A Kaplan turbine delivers 10 MW under a head of 25 m. The hub and tip diameters are 1.2 m and 3 m. Hydraulic and overall efficiencies are 0.90 and 0.85. 5.134)If both velocity triangles are right angled triangles, determine the speed guide blade-outlet angle and blade outlet angle. [DEC 13]