# JNTU Exam Papers

## Mechanics Of Fluids I-Sem Nov 2008

SET-2

1. (a) What is meant by Newtonian and non-Newtonian fluids. Explain with the

help of examples.

(b) A circular gate in a vertical wall has a diameter of 4m. The water surface on

the upstream side is 8m above the top of the gate and on the downstream side

1m above the top of the gate. Find the forces acting on the two sides of the

gate and the resultant force acting on the gate and its location. [8+8]

2. (a) Define and distinguish between steady flow and uniform flow. Give two examples of each flow.

(b) Derive continuity equation for 1-D flow. [8+8]

3. (a) What is momentum equation? Give applications of the equation.

(b) Water under a pressure of 345 kN /m2 is flowing through a 30 cm diameter

pipe at the rate of 0.25 m3 / s. If the pipe is bent by 1350 to the horizontal, find the magnitude and direction of the resultant force on the bend. Neglect losses. [8+8]

4. (a) What is meant by smooth boundary and a rough boundary?

(b) Describe briefly the phenomenon of boundary layer separation.

(c) At what wind speed must a 127 mm diameter sphere travel through water to have a drag of 5 N. [4+6+6]

5. (a) How are shocks formed? Give some practical examples.

(b) During a normal shock in a constant area duct containing air, the initial

conditions are P1 = 10N/m2, T1 = 00c; U = 1000 m/s Calculate (i) the corresponding trans shock condition and (ii) percentage change in density across

the shock if R= 287 J/Kg0k [8+8]

6. (a) Sketch the Reynolds apparatus and explain how the laminar flow can be demonstrated with the help of this apparatus.

(b) A viscous liquid was flowing in laminar regime in a 6 cm diameter circular pipe. A pitot tube at a radial distance of 2 cm from the axis indicated a velocity of 0.6 m/sec. Calculate the maximum velocity, the mean velocity and

the discharge in the pipe. [8+8]

7. (a) Define and explain the terms hydraulic gradient line and total energy line.

(b) A pipe 20cm diameter and 1800 m long connects two reservoirs one being 30m

below the other. The pipe line crosses a ridge whose summit is 7.5m above the upper reservoir. What will be the minimum depth of the pipe below the summit of the ridge in order that the pressure at the apex doesn’t fall below 7.5m vacuum. The length of the pipe from the upper reservoir to the apex is 300m. Taking f= 0.032 determine the rate of flow to the lower reservoir in lit/min. [8+8]

8. (a) A venturimeter has its axis vertical, the inlet and throat diameters being 150

mm and 75 mm respectively. The throat is 225 mm above inlet and k = 0.96, petrol of specific gravity 0.78 flows up through the meter at a rate of 0.029 m3/s. Find the pressure difference between the inlet and the throat.

(b) Explain the working procedure of Bourdon pressure gauge. [8+8]