Hall Ticket No Question Paper Code: AAE003
INSTITUTE OF AERONAUTICAL ENGINEERING
(Autonomous)
Four Year B.Tech III Semester End Examinations (Regular) November, 2018
Regulation: IARE R16
FLUID MECHANICS AND HYDRAULICS
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. Discuss Newton's law viscosity and explain how viscosity varies with temperature for liquids and
gases.
At a certain depth of a liquid where the pressure is 850 N/cm2 what will be the change in specific
volume and specific weight with respect to the surface? Given that the specific weight of that
liquid at the surface is 1025 N/cm3 and the bulk modulus of elasticity is 24x103 N/cm3.
2. A wooden cylinder of length L and diameter D is to be floated in stable equilibrium on a liquid
keeping its axis vertical. What should be the relation between L and D if the specific gravity of
liquid and that of the wood are 0.6 and 0.8 respectively?
Convert a pressure head of 10 m of water column to kerosene of specific gravity 0.8 and carbontetra-
chloride of specific gravity of 1.62.
UNIT II
3. An open circular cylinder of 15cm diameter and 100cm long contains water up to a height of
70cm. Calculate the speed at which the cylinder is to be rotated about its vertical axis so that
the axial depth becomes zero.
A uniform flow with a velocity of 3 m/s is flowing over a plane source of strength 30m2/s. The
uniform flow and source flow are in the same plane. A point P is situated in the flow field. The
distance of the point P from the source is 0.5 m and it is at an angle of 300 to the uniform flow.
Determine:
Stream function at point P
Resultant velocity of flow at P
4. Derive an expression for the continuity equation of a three dimensional fluid flow.
Given that u x2 y2 and v 2xy, determine the stream function and potential function for
the flow.
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UNIT III
5. Distinguish between Venturimeter and Orificemeter with neat sketches.
Water flows at the rate of 200 lit/sec upwards through a tapered vertical pipe. The diameter at
the bottom is 240 mm and at the top 200 mm and the length is 5m. The pressure at the bottom
is 8 bar, and the pressure at the topside is 7.3 bar. Determine the head loss through the pipe.
Express it as a function of exit velocity head.
6. State the Buckingham's Pi-theorem. Explain what are repeating variables and the guidelines for
their selection.
Two velocity components are given in the following case, find the third component such that they
satisfy the continuity equation.
U x3 y2 2z2; V x2y yz
ii)V 2y2;W 2xyz:
UNIT IV
7. Develop an expression for displacement thickness due to formation of boundary layer.
Water flows at a velocity of 1.2 m/s over a flat plate 1.2 m long. Determine the boundary layer
thickness and displacement thickness. Compare the values with values calculated using laminar
flow correlations
8. What are the minor losses in pipes? Give the appropriate formulae to calculate the losses.

Briefly explain Hydraulic Gradient Line and total energy Line.
UNIT V
9. Define cavitation and the reasons for its occurrence in hydraulic machines. Describe the effects
of cavitation and the ways in which it could be avoided.
Differentiate pump and turbine. Draw velocity triangle for a pump in ideal flow condition.
10. A typical household basement sump pump provides a discharge of 5gal/min against a head of 15
ft. Estimate
the maximum efficiency and
the minimum horsepower required to drive such a pump at 1750 r/min.
Discuss briefly about the classification of Hydraulic Turbines according to the direction of flow
through runner.