Hall Ticket No Question Paper Code: AAE003
INSTITUTE OF AERONAUTICAL ENGINEERING
(Autonomous)
B.Tech III Semester End Examinations (Regular) December, 2017
Regulation: IARE R16
FLUID MECHANICS AND HYDRAULICS
(Aeronautical Engineering)
Time: 3 Hours Max Marks: 70
Answer ONE Question from each Unit
All Questions Carry Equal Marks
All parts of the question must be answered in one place only
UNIT I
1. Explain the Newton's law of viscosity.
Two horizontal plates are placed 1.25 cm apart, the space between them being filled with oil of
viscosity 14 poises. Calculate the shear stress in oil if upper plate is moved with a velocity of 2.5
m/s.
2. State and prove Pascal's law.
A rectangular plane surface 3 m wide and 4 m deep lies in water in such a way that its plane
makes an angle of 30 with the free surface of water. Determine the total pressure force and
position of centre of pressure, when the upperedge is 2 m below the free surface.
UNIT II
3. Define: steady flow, uniform flow, laminar flow and two dimensional flow.
A 30 cm diameter pipe, conveying water, branches into two pipes of diameters 20 cm and 15 cm
respectively. If the average velocity in the 30 cm diameter pipe is 2.5 find the discharge in
this pipe. Also determine the velocity in 15 cm pipe if the average velocity in 20 cm diameter
pipe is 2 m/s.
4. The velocity components in a two dimensional flow are u y3
3 and v xy2 x3
3 .
Show that these components represent a possible case of an irrotational flow.
A stream function is given by Calculate the velocity components and also magnitude
and direction of the resultant velocity at any point.
UNIT III
5. A conical tube of length 2 m is fixed vertically with its smaller end upwards. The velocity of flow
at the smaller end is 5 m/s while at the lower end it is 2m/s. the pressure head at the smaller
end is 2.5 m of liquid. The loss of head in the tube is 0:35(v1 where v1 is the velocity
at smaller end and v2 at the lower end respectively. Determine the pressure head at the lower
end. Flow takes place in the downward direction.
Page 1 of 2
Figure 1
List the practical applications of Bernoulli's equation.
6. What is a venturimeter? Derive an expression for the discharge through a venturimeter.
The water is flowing through a pipe having diameters 20 cm and 10 cm at a sections 1 and 2
respectively. The rate of flow through pipe is 35 litres/s. The section 1 is 6 m above datum and
section 2 is 4 m above datum. If the pressure at section 1 is 39.24 N/cm2, find the intensity of
pressure at section 2.
UNIT IV
7. Derive Darcy Weisbach equation.
Determine the rate of flow of water through a pipe of diameter 20 cm and length 50 m when
one end of the pipe is connected to a tank and other end of the pipe is open to the atmosphere.
The pipe is horizontal and the height of water in the tank is 4 m above the centre of the pipe.
Consider all minor losses and take f 0.009 in the formula hf 4fLV 2
d2g
8. Explain briefly boundary layer characteristics.
A flat plate of 1.2 m wide and 1 m long is held in air flow of velocity 5m/s parallel to the flow.
Find the boundary layer thickness at the end of the plate and the drag on the plate.
UNIT V
9. Define hydraulic efficiency and overall efficiency of pumps.
The quantity of water available for a hydroelectric power station is 260 m3/sec and a head of
1.73 m. If the speed of the turbine is to be 50 rpm and the efficiency 82.5%. Find the number of
turbines required. Assume specific speed Ns 760.
10. Write the equation for Euler turbo machine.
A turbine is to operate under a head of 25 m at 200 rpm. The discharge is 9 cm3/sec. If the
efficiency is determine:
i. specific speed of the machine
ii. power generated