ME 34 FLUID MECHANICS AND MACHINERY

THE RAJAAS ENGINEERING COLLEGE

Vadakkangulam – 627116.

DEPARTMENT OF MECHANICAL ENGINEERING

INTERNAL TEST -1

                                     ME 34  FLUID MECHANICS AND MACHINERY

YEAR /SEM : II/III                                                                           Max. Marks : 50

Date :02-09-‘10                                                                                   Time : 2 hours.

Part - I :                                                                                                           5 X 2 = 10

1. Define viscosity and specific gravity.
2. Define surface tension and capillarity.
3. Write the different types of fluids.
4. Define laminar and turbulent flow.
5. Write the Euler’s equation, Bernoulli’s equation and continuity equation.

Part - II: Answer any five                                                                                                       5 X 8 = 40

1. A converging pipe is 20 cm inlet and 10 cm outlet and 5 m long is lying in the vertical plane making an angle 45^o to the horizontal. The pipe is carrying the water 24 m³/min. The pressure of the water at the inlet is 50 N/cm². Find the pressure of the water at the exit.
2.  A converging pipe of 30 cm and 15 cm diameter carrying water is positioned inclined whose inlet and outlet are at 6m above the datum. The pressure at inlet is 1.5 bar and velocity is 5m/s. Find the pressure of water at the outlet of the pipe. Neglect the losses.
3. Calculate the capillary effect in glass tube of 5mm diameter when immersed in (i) water and (ii) mercury.

Take

 σ (Water in contact with air) = 0.075 N/m

 σ (mercury in contact with air) = 0.52 N/m

 ρ (water) = 1000kg/m³ and ρ (mercury) = 13600 kg/m³

 The contact angle for water is 0^o and for mercury 130^o.

4. A plate, 0.5 mm distance from the fixed plate moves with 50 cm/sec and requires 5N/m² force to maintain the speed of moving plate. Determine the viscosity of the oil between the plates.
5. A jet of water from a 25mm diameter nozzle is directed vertically upwards. Assuming that the jet remains circular and neglecting any loss of energy, that will be the diameter at a point4.5m above the nozzle, if the velocity with which the jet leaves the nozzle is 12m/s.
6. A 30 cm diameter pipe, conveying water, branches into two pipes of diameters 20cm and 15 cm respectively. If  the average velocity in the 30 cm diameter pipe is 2.5 m/s, find the discharge in this pipe. Also determine the velocity in 15 cm pipe if the average velocity in 20cm diameter pipe is 2m/s.