nagpurstudents - tgpcetb) in an inward flow reaction turbine the head on the turbine is 32 m. the...
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NagpurStudents.Org
Special Thanks to Abhijith Alolickal
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NagpurStudents.Org
Special Thanks to Abhijith Alolickal
Scanned by CamScanner
NagpurStudents.Org
Special Thanks to Abhijith Alolickal
Scanned by CamScanner
NagpurStudents.Org
Special Thanks to Abhijith Alolickal
Scanned by CamScanner
NagpurStudents.Org
Special Thanks to Abhijith Alolickal
Scanned by CamScanner
NagpurStudents.Org
Special Thanks to Abhijith Alolickal
Scanned by CamScanner
NagpurStudents.Org
Special Thanks to Abhijith Alolickal
NRJ/KW/17/4425/4451 1 P.T.O
B.E. (Mechanical Engineering / Power Engineering) Fourth Semester (C.B.S.) Hydraulics Machines
P. Pages : 3 NRJ/KW/17/4425/4451
Time : Three Hours Max. Marks : 80
_____________________________________________________________________
Notes : 1. All questions carry marks as indicated.
2. Solve Question 1 OR Questions No. 2.
3. Solve Question 3 OR Questions No. 4.
4. Solve Question 5 OR Questions No. 6.
5. Solve Question 7 OR Questions No. 8.
6. Solve Question 9 OR Questions No. 10.
7. Solve Question 11 OR Questions No. 12.
8. Assume suitable data whenever necessary.
9. Illustrate your answers whenever necessary with the help of neat sketches.
1. a) Derive the expression for sonic velocity for one dimensional flow with a neat sketch.
7
b) A gas with a velocity of 300 m/s is flowing through a horizontal pipe at a section where
pressure is 2m/kN78 absolute and temperature 40 ºC. The pipe changes in diameter and at
this section, the pressure is 2m/kN117 absolute. Find the velocity of the gas at this section
if the flow of the gas is adiabatic.
Take k.kg/J287R and 4.1 .
OR
7
2. a) Derive the expression for stagnation pressure in compressible flow with a neat sketch.
7
b) An aeroplane is flying at 1000 km/hr through still air having a pressure of 2m/kN5.78
(absolute) and temperature Cº8 . Calculate on the stagnation point on the nose of the
plane.
i) Stagnation pressure
ii) Stagnation temperature and
iii) Stagnation density.
7
3. a) Draw neat sketch for Pelton wheel bucket and Explain why jet is deflected through 160 to
170º?
6
b) A Pelton wheel is receiving water from a penstock with a gross head of 510 m. one third
of gross head is lost in friction in the penstock. The rate of flow through the nozzle fitted
at the end of the penstock is s/m2.2 3 . The angle of deflection of the Jet is 165º.
Determine
i) The power given by water to the runner and
ii) Hydraulic efficiency of the Pelton wheel.
Take coefficient of velocity - 1.0 and speed ratio = 0.45.
OR
7
4. a) Explain the elements of hydroelectric power plant with neat sketch indicating various
important heads.
6
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NRJ/KW/17/4425/4451 2
b) A Pelton wheel of 1.1 m mean bucket diameter works under a head of 500 m. The deflection
of jet is 165º and its relative velocity is reduced over the bucket by 15 percent due to friction.
If the diameter of Jet is 100 mm and the water is to leave the bucket without any whirl,
determine :
i) Rotational speed of wheel.
ii) Ratio of bucket speed to jet velocity.
iii) Impulsive force and power developed by wheel.
iv) Available power
v) Power input to buckets and
vi) Efficiency of the wheel with power input to bucket as reference point. Take .97.0Cv
7
5. a) Explain the role of following in reaction turbine.
i) Casing ii) Guide vanes
iii) Draft tube iv) Runner vanes
6
b) The following data pertain to an inward flow reaction turbine :
Net head = 86.4 m, speed of runner = 650 rpm, shaft power = 397 kW, Ratio of wheel width
to wheel diameter at inlet = 0.10, Ratio of inner diameter to outer diameter = 0.5, Flow ratio
= 0.17, Hydraulic efficiency = 95%, Overall efficiency = 85%, Flow velocity is constant,
discharge is radial. Neglecting blockage by blades, find the dimensions and blade angles of
the turbine.
OR
7
6. a) Derive the expression for draft tube efficiency and with neat sketch indicating various
heads.
6
b) The propeller reaction turbine of runner diameter 4.5 m is running at 48 rpm. The guide
blade angle at inlet is 145º and the runner blade angle is 25º to the direction of vane. The
axial flow area of water through the runner is 2m30 . If the runner blade angle at inlet is
radial.
Determine :
i) Hydraulic efficiency of the turbine.
ii) Discharge through the turbine, and
iii) Power developed by the runner.
7
7. a) Explain the components of centrifugal pump and installation with neat sketch.
6
b) A centrifugal pump has the following dimensions :
Inlet radius = 80 mm, outlet radius = 160 mm, width of impeller at the inlet = 50 mm, vane
angle of inlet 45.01 radians, vane angle at exit 25.02 radians, width of impeller at
outlet = 50 mm. Assuming shockless entry determine the discharge and head developed by
the pump when the impeller rotates at 90 rad/s.
OR
7
8. a) Explain the effect of outlet vane angle ( ) on manometric efficiency of centrifugal pump.
6
b) A three stage centrifugal pump has impellers 400 mm in diameter and 20 mm wide at outlet.
The vanes are curred back at the outlet at 45º and reduce the circumferential area by 10
percent, the manometric efficiency is 90% and the overall efficiency is 80%. The pump is
running at 1000 rpm and delivering s/m05.0 3 .
Determine :
i) Head generated by the pump and
ii) Shaft power required to run the pump.
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9. a) Derive the expression for percentage of work saved in pipe friction by fitting air vessels in
single acting reciprocating pump.
6
b) Determine the maximum speed at which a double acting reciprocating pump can be operated
under the following conditions
a) No air vessel on the suction side
b) A very large air vessel on the suction side, close to the pump.
The suction lift is 4 m, length of suction pipe 6.5 m, diameter of suction pipe 100 mm,
diameter of piston 150 mm and length of stroke is 0.45 m. Assume suitable harmonic
motion, atmospheric pressure head as 10.3 m of water and separation occurs at 2.6 m of
water absolute. Take Darcy's factor, f = 0.024.
OR
7
10. a) Explain the effect of acceleration in suction and delivery pipe on Indicator diagram for
reciprocating pump.
6
b) A single acting reciprocating pump running at 60 rpm, delivers 3m53.0 of water per minute.
The diameter of the piston is 200 mm and stroke length 300 mm. The suction and delivery
head are 4 m and 12 m respectively.
Determine :
i) Theoretical discharge
ii) Coefficient of discharge
iii) Percentage slip of the pump, and
iv) Power required to run the pump.
7
11. a) Explain different dimensionless numbers and their significance with mathematical
relations.
6
b) A hydraulic turbine is to develop 1015 kW when running at 120 rpm under a net head of
12m. work out the maximum flow rate and specific speed for the turbine if the overall
efficiency at the best operating point is 92%. In order to predict its performance, a 1 : 10
scale model is tested under a head of 7.2 m. What would be the speed, power output and
water consumption of the model if it runs under the conditions similar to the prototype.
OR
8
12. Write short note any three.
i) Air lift pumps.
ii) Submersible pumps
iii) Regenerative pump
iv) Similitude and types of similarities.
v) Hydraulic ram.
************
14
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NagpurStudents.Org
KNT/KW/16/7285/7311 1 P.T.O
B.E. Fourth Semester (Mechanical Engineering / Power Engineering) (C.B.S.) Hydraulics Machines Paper - III
P. Pages : 3 KNT/KW/16/7285/7311
Time : Three Hours Max. Marks : 80
_____________________________________________________________________
Notes : 1. All questions carry marks as indicated.
2. Solve Question 1 OR Questions No. 2.
3. Solve Question 3 OR Questions No. 4.
4. Solve Question 5 OR Questions No. 6.
5. Solve Question 7 OR Questions No. 8.
6. Solve Question 9 OR Questions No. 10.
7. Solve Question 11 OR Questions No. 12.
8. Assume suitable data whenever necessary.
9. Illustrate your answers whenever necessary with the help of neat sketches.
10. Use of non programmable calculator is permitted.
1. a) What is sonic velocity? prove that velocity of sound wave in a compressible fluid is given
by :
d
dpC where, P is fluid pressure in pipe and is the density of the fluid.
7
b) A 120 mm dia. pipe reduces to 60 mm dia. through a sudden contraction. It carries air at
25º C under isothermal condition. The absolute pressures in the two pipes before and after
the contraction are 480 kN/m2 and 384 kN/m2 respectively.
Determine.
i) Densities at the two sections.
ii) Velocities at the two sections.
iii) Mass flow rate.
Take R = 287 J/kg.k
6
2. a) At some section in the convergent- divergent nozzle, in which air is flowing, pressure,
velocity, temperature and cross-sectional area are 200 kN/m2, 170 m/s, 200º C and
1000 mm2 respectively. If the flow conditions are isentropic, determine.
i) Stagnation temperature and stagnation pressure.
ii) Sonic velocity and Mach number at this section.
iii) Velocity, Mach number and flow area at outlet section where pressure is 110 kN/m2.
iv) Pressure, temperature, velocity and flow area at throat of the nozzle.
Take for air : R = 287 J/kgK.
CP = 1.0 kJ/kgk, and r = 1.4.
9
b) Discuss in detail, ''Normal shock wave'' with neat sketch.
4
3. a) Explain the elements of hydroelectric power plant with neat sketch.
6
b) A Pelton wheel is receiving water from a penstock with gross head of 510 m. one-third of
gross head is lost is friction in the penstock. The rate of flow through the nozzle fitted at
the end of the penstock is 2.2 m3/s. The angle of deflection of the jet is 165º. Determine.
i) The power given by water to the runner and.
ii) Hydraulic efficiency of the pelton wheel.
Take. 0.1Cv and speed ratio = 0.45.
8
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4. a) A Pelton wheel is designed for following specification: ,kW9560Power
,rpm750Speed,m350Head
Overall efficiency = 85%
jet diameter is not to exceed 1/6th of the wheel diameter.
Determine the following.
i) Wheel diameter.
ii) Diameter of Jet.
iii) No. of Jets required.
Take : 45.0ratioSpeed,985.0Cv .
9
b) Explain with neat sketches performance characteristic curves for Pelton turbine.
5
5. a) Explain the governing of a reaction turbine with a neat sketch.
6
b) In an inward flow reaction turbine the head on the turbine is 32 m. The external and
internal diameters are 1.44 m and 0.72 m respectively. The velocity of flow through the
runner is constant and equal to 3 m/s. The guide blade angle is 10º and the runner vanes
are rigid at inlet. If the discharge at outlet is radial, determine.
i) The speed of the turbine.
ii) The vane angle at outlet of the runner, and.
iii) Hydraulic efficiency.
8
6. a) What are the functions of Draft Tube? Explain different types of draft tubes with suitable
sketches.
6
b) The hub diameters of Kaplan turbine working under a head of 12 m, is 0.35 times the
diameter of runner. The turbine is running at 100 rpm. If the vane angle of the extreme
edge of the runner at outlet is 15º and flow ratio is 0.6, find.
i) Diameter at runner.
ii) Diameter of boss
iii) Discharge through runner.
The velocity of whirl at outlet is given as zero.
8
7. a) With a neat Sketch explain different components of a centrifugal pump.
6
b) A Centrifugal pump is running at 1000 rpm. The outlet vane angle of the impeller is 45º
and velocity of flow at outlet is 2.5 m/s. The discharge through the pump is 200 litres/s
when the pump is working against a total head of 20 m. If the manometric efficiency of
pump is 80%, determine.
i) Outside diameter of impeller.
ii) Width of impeller at outlet.
7
8. a) What is multi-staging in centrifugal pumps? Explain with neat sketches pumps in series
and in parallel.
6
b) A centrifugal pump has discharge of 1565 liters/sec against a mean lift of 6.1 m. When it
rotates at 200 rpm. The impeller diameter is 1.22 m and the area at outer periphery is
6450 cm2. If the vanes are set back at an angle of 26º at the outlet, determine.
i) Hydraulic efficiency.
ii) Power required to drive the pump.
iii) Minimum Speed to start pumping if the ratio of external to internal diameter is 2.
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9. a) Explain the Indicator diagram of reciprocating pump with neat sketch.
6
b) A single acting reciprocating pump having a bore of 150 mm and a stroke of 300 mm is
raising water to a height of 20 m above the sump level. It has actual discharge of
0.0052 m3/s and efficiency 70%. If the speed of the pump is 60 rpm, determine.
i) Theoretical discharge.
ii) Theoretical power.
iii) Actual power.
iv) Percentage slip.
7
10. a) Explain Air vessels with neat sketch.
6
b) A 'Three throw' pump has cylinders of 250 mm diameter and stroke of 500 mm each. The
pump is required to deliver 0.1 m3/s at a head of 100 m. friction losses are estimated tobe
1m in sanction pipe and 19 m in Delivery pipe. Velocity of water in delivery pipe is 1 m/s,
overall efficiency is 85% and the slip is 3%.
Determine.
i) Speed of the pump, and.
ii) Power required to run pump.
7
11. a) Explain any three dimensionless numbers with mathematical formula and their
significance.
5
b) Two geometrically Similar Pumps are running at the same speed of 1000 rpm. one pump
has an impeller diameter of 0.30 m and lifts water at the rate of 20 litres/sec against a head
of 15 m. Determine the head and impeller diameter of the other pump to deliver half the
discharge.
8
12. Write short notes on any three.
i) Air lift pump.
ii) Specific speed for turbine and pump.
iii) Submersible pump.
iv) Cavitation in Reciprocating pump.
13
******
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KNT/KW/16/7285/7311 4
NagpurStudents.Org
TKN/KS/16/7373/7399 1 P.T.O
B.E. (Mechanical Engineering / Power Engineering) Fourth Semester (C.B.S.) Hydraulics Machines Paper - III
P. Pages : 3 TKN/KS/16/7373/7399
Time : Three Hours Max. Marks : 80
_____________________________________________________________________
Notes : 1. All questions carry marks as indicated.
2. Solve Question 1 OR Questions No. 2.
3. Solve Question 3 OR Questions No. 4.
4. Solve Question 5 OR Questions No. 6.
5. Solve Question 7 OR Questions No. 8.
6. Solve Question 9 OR Questions No. 10.
7. Solve Question 11 OR Questions No. 12.
8. Due credit will be given to neatness and adequate dimensions.
9. Assume suitable data whenever necessary.
10. Use of non programmable calculator is permitted.
1. a) Derive an expression for area velocity relationship for a compressible fluid in the form
1MV
dV
A
dA 2 .
6
b) Determine the speed and Mach number of a supersonic aircraft flying at an attitude of 1000
m where the temperature is 280 K. Sound of the aircraft is heard 2.15 seconds after the
passage of air craft over the head of an observer.
Take Y = 1.41 and R = 287 J/kg K.
OR
7
2. a) What do you mean by compressibility correction factor? Find an expression for
compressibility factor.
6
b) Air flows through a convergent – divergent nozzle. At some section in the nozzle pressure
= 2 bar, velocity = 170 m/s, and temp = 200ºC and cross sectional area = 1000 mm2.
Assuming isentropic flow conditions determine :
a) Stagnation temperature and pressure.
b) Sonic velocity and Mach number at this section.
c) Velocity, Mach number and flow area at outlet section where pressure is 1.1 bar.
d) Pressure, temperature, velocity and flow area at throat of the nozzle
Take R = 287 J/kgK
Cp = 1000 J/kg K and
Y = 1.4
7
3. a) Draw a neat sketch and explain the characteristic features of pelton wheel bucket.
What are the limitations in keeping the deflection angle of the jet less than 180º?
6
b) A Pelton wheel is required to develop 6 MW under a head of 300 m. If rotates with a
speed of 550 rpm. Assuming Jet ratio as 10 and over all efficiency as 85%.
Determine :
i) Diameter of wheel
ii) Quantity of water required.
iii) Number of jets.
Take : Cv = 0.98 and Ku = 0.46.
OR
7
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4. a) Draw a general layout of a hydroelectric power plant using impulse turbine and explain
briefly its construction and working.
6
b) A single jet Pelton wheel runs at 300 rpm under a head of 510 m. The jet diameter is 200
mm, its deflection inside the bucket is 165º and its relative velocity is reduced by 15% due
to friction. Determine
i) Water power
ii) Resultant force on the bucket
iii) Overall efficiency.
Take Co – efficient of velocity = 0.98 and speed ratio = 0.46
7
5. a) What is cavitation? How can it be avoided in reaction turbines.
7
b) The following data pertains to an inward flow reaction turbine.
Net head = 86.4 m. Speed = 650 rpm
Output power = 397 KW
Hydraulic efficiency = 95%
Overall efficiency = 85%
Flow ratio = 0.17 Breadth Ratio = 0.1
Ratio of inner diameter to outer diameter = 0.5
Flow velocity constant and
Discharge radial.
Neglecting blockage by blades,
Find dimensions and blade angles of the turbine.
OR
7
6. a) What is governing and how it is accomplished in Reaction turbines?
7
b) A Kaplan turbine develops 22000 KW at an average head of 35m. Assuming a speed ratio
of 2, flow ratio of 0.6 diameter of boss equal to 0.35 times the diameter of the runner and
overall efficiency of 88 percent, Calculate the diameter, speed and specific speed of the
turbine.
7
7. a) Show that the pressure rise of a centrifugal pump when frictional and other losses are
neglected is given by 222
22
21
cosecfVufVg2
1
where 21 fV,fV velocities of flow at inlet and outlet respectively.
2u tangential velocity at outlet
vane angle at outlet.
7
b) A centrifugal pump is required to discharge 0.118 m3 of water per second against a head of
25m. When rotating at 1500 rpm. The manometric efficiency is 75%. The impeller diameter
is 250 mm and its width at outlet is 50 mm. Determine the vane angle at the outer periphery
of the impeller.
OR
7
8. a) What do you mean by "NPSH' Net positive suction heads? What is its importance.
7
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TKN/KS/16/7373/7399 3 P.T.O
b) A three stage centrifugal pump has impellers 400 mm in diameters and 20 mm wide at
outlet. The vanes are curved back at the outlet at 450 and reduce the circumferential area by
10%. The manometric efficiency is 90% and the overall efficiency is 80%. The pump is
running at 1000 rpm. and delivering s/m05.0 3 .
Determine :
i) Head generated by the pump and
ii) Shaft power required to run the pump.
7
9. a) Define indicator diagram. Prove that work done by the reciprocating pump is proportional
to the area of indicator diagram.
6
b) A three throw has cylinder of 250mm diameter and stroke of 500 mm each. The pump is
required to deliver s/m1.0 3 at a head of 100 m. Friction losses are estimated to be 1m in
suction pipe and 19 m in delivery pipe. Velocity of water in delivery pipe is 1 m/s, overall
efficiency is 85% and slip is 3%.
Determine :
i) Speed of the pump and
ii) Power required to drive the pump.
OR
7
10. a) What is negative slip in reciprocating pump? Explain with neat sketches the function of air
vessels in reciprocating pump.
6
b) The bore and stroke of a reciprocating pump are 250 mm and 500 mm respectively. The
pump delivers water trough a 100 mm delivery pipe to a tank located at 14 m above it and
27 m horizontally from it. If separation occures at 2m/KN22 absolute, find the safe speed
at which pump should run when
i) The delivery pipe is horizontal from the pump and then vertical upto the tank. and
ii) The delivery pipe is vertical from the pump and then horizontal upto the tank. The
atmospheric pressure is 10.3 m of water.
7
11. a) What are the various methods of dimensional analysis to obtain a functional relationship
between various parameters affecting a physical phenomenon.
6
b) A model turbine constructed to a scale of 1 : 10 when tested under a head of 8 m and 400
rpm. Gave an efficiency of 77 percent. Determine the rpm of the prototype and the ratio of
powers developed by the model and prototype. If the prototype works under a head of
400 m?
OR
7
12. Write short notes on any three.
i) Air Lift Pump. ii) Hydraulic Ram
iii) Submersible Pump. iv) Regenerative Pump.
*********
13
NagpurStudents.Org
TKN/KS/16/7373/7399 4
NagpurStudents.Org
NJR/KS/18/4425/4451 1 P.T.O
B.E. (Mechanical Engineering / Power Engineering) Fourth Semester (C.B.S.) Hydraulics Machines
P. Pages : 3 NJR/KS/18/4425/4451
Time : Three Hours Max. Marks : 80
_____________________________________________________________________
Notes : 1. All questions carry marks as indicated.
2. Solve Question 1 OR Questions No. 2.
3. Solve Question 3 OR Questions No. 4.
4. Solve Question 5 OR Questions No. 6.
5. Solve Question 7 OR Questions No. 8.
6. Solve Question 9 OR Questions No. 10.
7. Solve Question 11 OR Questions No. 12.
8. Assume suitable data whenever necessary.
9. Illustrate your answers whenever necessary with the help of neat sketches.
10. Use of non programmable calculator is permitted.
1. a) Prove that the velocity of sound wave in a compressible fluid is given by C k= where
k and are the bulk modules and density of fluid respectively.
6
b) A supersonic aircraft flies at an altitude of 1.8km where temperature is 4ºC. Determine the
speed of an aircraft if its sound is heard 4 seconds after its passage over the head of an
observer.
Take R = 287 J/kg k y = 1.4.
7
OR
2. a) Derive an expression for area velocity relationship for a compressible fluid in the form.
( )2dA dvM 1
A v= − .
6
b) A tank fitted with a convergent nozzle contains air at a temperature of 20ºC. The diameter
at the outlet of the nozzle is 25mm. Assuming adiabatic flow find the mass flow rate of flow
air through the nozzle to the atmosphere when the pressure in the tank is.
i) ( )2140 kN m abs ii) 2300 kN m
Take for air R = 287 J/kg k, y = 1.4, Barometric Pressure = 100 2kN m .
7
3. a) Draw neat sketch of Pelton wheel bucket and explain why undercut is provided? Why jet
is not deflected through 180º?
7
b) A Pelton wheel is to be designed for following specifications.
Shaft Power = 9560kW
Head = 350 Meters
Speed = 750 RPM
Overall efficiency = 85%
Jet dia - Not to exceed 1/6th of the wheel diameter
Determine the following.
i) The wheel diameter ii) The diameter of jet
iii) Number of jets required.
Take VC = 0.985 Speed Ratio = 0.45.
7
OR
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4. a) Derive an expression for maximum efficiency of a Pelton Wheel.
7
b) A Pelton wheel is required to develop 4000 kW under a head of 350m. There are two equal
jets and the bucket deflection angle is 165º, overall efficiency - 85%, vC =0.97, nK 0.46=
and relative velocity at exit reduces by 14% the relative velocity at inlet.
Calculate:
i) Diameter of the bucket ii) Diameter of Jet
iii) Hydraulic efficiency of the turbine
7
5. a) What is governing and how it is accomplished in Reaction Turbines?
6
b) The following data is given for Francis turbine.
Net Head = 60m, Speed = 750RPM, Shaft Power = 295kW, o h84% 93%, = = Flow
Ratio = 0.2, Breadth Ratio = 0.1,
Outer diameter = 2 x inner diameter, Thickness of vanes occupy 5% of area, Velocity of
flow is constant and Discharge from turbine is Radial.
Determine:
i) Guide blade angle
ii) Runner vane angle at inlet & outlet
iii) Dia of runner at inlet & outlet
iv) Width of wheel at inlet.
7
OR
6. a) What are the functions of Draft tube? Explain different types of draft tube with suitable
sketches.
6
b) A Kaplan turbine runner is to be designed to develop 7357.5kW of power. The net head
available is 10m. Assume speed ratio is 1.8 and flow ratio is 0.6.
If the overall efficiency is 70% and the diameter of the boss is 0-4 times the diameter
of runner
Find:
i) The diameter of Runner
ii) Speed of the Runner and
iii) Specific Speed
7
7. a) Show that the pressure rise in the centrifugal pump is given by:
2 2 2 21 2 2
1Vf , U Vf cosec
2g + −
Where 1 2Vf , Vf → velocities of flow at inlet and outlet
2U → Velocity of Vane at outlet
→ Vane angle at outlet.
6
b) The impeller of a centrifugal pump having external and internal diameter 50cm and 25cm
respectively, width at outlet is 5cm and running of 1200RPM, it works against a head of
48m. The velocity of flow through impeller is constant and equal to 3 m/s. The Vanes are
set back at an angle of 40º at outlet. Determine.
i) Inlet Vane angle
ii) Work done by the Impeller and
iii) Manometric efficiency.
7
OR
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8. a) What is multistaging in centrifugal pumps? Explain with neat sketches pumps in series
and in parallel.
6
b) A centrifugal pump impeller has an outlet diameter of 360mm and width 60mm. The Vanes
are curved backwards at 35º. and thickness of Vanes occupy 20% of the area of flow, the
velocity of flow is constant from inlet to outlet. The pump rotates at 800 RPM. If the rate
of flow through the pump is 30.13m s . Determine.
i) Pressure rise in the impeller
ii) The percentage of total work converted to kinetic energy.
7
9. a) Define Indicator diagram prove that work done by reciprocating pump is proportional to
the area of indicator diagram.
7
b) A single acting reciprocating pump has the plunger diameter of 20cm and stroke of 30cm.
The pump discharges 30.53m min at 60 rpm.
Find the theoretical discharge, co-efficient of discharge, and percentage slip of pump.
Further if suction and delivery heads are 4m and 12m respectively work out power required
to drive the pump.
7
OR
10. a) What is negative slip? Explain with neat sketches the function of air vessels in reciprocating
pump.
7
b) A single acting reciprocating pump has a diameter of Piston 15cm and stroke length of
35cm. the centre of the pump is 3.5m above the water surface in sump and 22m below the
delivery water level. Both the suction and delivery pipes have the same diameter of 10cm
and are 5m and 30m long respectively. If the pump is working at 30rpm.
Determine:
i) The pressure heads on the Piston at the beginning, middle and end of both suction and
delivery strokes.
ii) The Power required to drive the pump.
7
11. a) What are the various methods of dimensional analysis to obtain a functional relationship
between various parameters affecting a physical phenomenon.
6
b) A centrifugal pump is discharging 0-025 3m s of water against a total head of 18m. The
diameter of the impeller is 0.4m and it is rotating at 1400 r.p.m. Calculate the head,
discharge and ratio of powers of a geometrically similar pump of diameter 0.25m when it
is running at 2800 r.p.m.
7
OR
12. Write short notes on any three.
i) Air Lift Pump ii) Submersible pump
iii) Regenerative Pump iv) Hydraulic Ram
v) Specific speed for Turbine and Pump
13
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