DHAANISH AHMED COLLEGE OF ENGINEERINGAn ISO 9001-2008 Certified Institution

Approved By AICTE, New Delhi and Affiliated To Anna UniversityDEPARTMENT OF MECHANICAL ENGG.

ASSIGNMENT 1

SUBJECT : FLUID MECHANICS AND MACHINERY SUBMISSION DATE:SUB. CODE : CE 6451 YEAR/ SEM : II/III

1. Inside a 60 mm diameter cylinder a piston of 59mm diameter rotates concentrically. Both the cylinder and piston are 80mm long. If the space between cylinder and the piston is filled with oil of viscosity of 0.3N-s/m2 and a torque of 1.5 N-m is applied. Find the rpm of the piston and power required.

2. A pipe of 300 mm diameter inclined at 300 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/m2 and 80 kN/m2 respectively. Find out the coefficient of discharge of Venturimeter if the flow is 0.20 m3/s.

3. The dynamic viscosity of an oil, used for lubrication between a shaft and sleeve is 6 poise. The shaft is diameter 0.4 m and rotates at 190 r.p.m. Calculate the power lost in the bearing for a sleeve length of 90 mm. The thickness of the oil film is 1.5 mm

4. The dynamic viscosity of oil, used for lubricating between a shaft and sleeve is 10Poise. The shaft rotates at 200 rpm. The power lost in the bearing for a sleeve length of 100mm is 25 Watts. The thickness of the oil film is 1.5mm. Calculate the diameter of the shaft and the sleeve.

5. A horizontal venturimeter with inlet diameter 20 cm and throat diameter 10 cm is used to measure the flow of water. The pressure at inlet is 17,658 N/cm2 and the vacuum pressure at the throat is 30 cm of mercury. Find the discharge of water through venturimeter. Take Cd = 0.98.

6. Find the discharge of water flowing through a pipe 30cm diameter placed in an inclined position where a venturimeter is inserted, having a throat diameter of 15 cm. The difference of pressure between the main and the throat is measured by a liquid of specific gravity 0.6 in a inverted U tube which gives a reading of 30cm. The loss of head between the main and the throat is 0.2 times the kinetic head of the pipe.

7. A laminar flow taking place in a pipe of diameter 200mm. The maximum velocity is 1.5 m/s. Find the mean velocity and the radius at which this occurs. Also calculate the velocity at 4 cm from the wall of the pipe.