Hall Ticket No Question Paper Code: ACE005
INSTITUTE OF AERONAUTICAL ENGINEERING
(Autonomous)
B.Tech IV Semester End Examinations (Regular) - May, 2018 Regulation: IARE – R16
FLUID MECHANICS
Time: 3 Hours (CE) 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. (a) Explain the following terms related to fluids. [7M]
i. Newtonian and Non Newtonian fluids ii. Surface tension
iii. Specific gravity iv. Viscosity
(b) A cubical blade of 20cm edge and weight 20kg(F) is allowed to slide down a plane inclined at 20 degree to the horizontal on which there is thin film of oil of viscosity 0.22 x 10−3 kg(F)
−s/m2.What terminal velocity will be attained by the block if the film thickness is estimated to
be 0.025mm? [7M]
2. (a) The left leg of a U-tube mercury manometer is connected to a pipeline conveying water, the level of mercury in the leg being 0.6m below the centre of pipeline, and the right leg in open to atmosphere. The level of mercury in the right leg is 0.45m above that in the left leg and the space above mercury in the right leg contain benzene (specific gravity 0.88) to a height of 0.3m.
Find the pressure in the pipe. [7M]
(b) A vertical gate closes a horizontal tunnel 5m high and 3m wide running full with water. The pressure at the bottom of the gate is 196.2 KN/m2. Determine the total pressure on the gate
and position of the centre of pressure. [7M]
UNIT – II
3. (a) Differentiate between the following fluid flows [7M]
i. Steady flow and Unsteady flow.
ii. Uniform flow and Non uniform flow
(b) The diameter of a pipe at the sections 1 and 2 are 10cm and 15cm respectively. Find the discharge through the pipe if the velocity of water flowing through the pipe at section 1 in 5m/s. Also,
determine the velocity at section 2. [7M]
4. (a) The following cases represent the two velocity components; determine the 3rd component of
velocity such that they satisfy the continuity equation. [7M]
i. U =x2+y2+z2;V =xy2−yz2+xy ii. V = 2y2, W = 2xyz
(b) A stream function is given as 5x-6y. Calculate the velocity components and also magnitude and
direction of the resultant velocity at any point. [7M]
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UNIT – III
5. (a) A pitot-static tube placed in the centre of a 300 mm pipeline has one orifice pointing upstream and other perpendicular to it. The mean velocity in the pipe is 0.80 of the central velocity. Find the discharge through the pipe if the pressure difference between the two orifices is 60 mm of
water. Take the co efficient of Pitot tube as cv=0.98. [7M]
(b) Obtain Bernoulli’s equation from Euler’s equation. State the assumptions made in the derivation
of Bernoulli’s equation. [7M]
6. (a) A horizontal venturimeter with inlet and throat diameter 30cm and 15cm respectively is used to measure the flow of water. The reading of differential manometer connected to the inlet and the throat is 20 cm of mercury. Determine the rate of flow, take Cd=0.98. [7M]
(b) An orifice meter with orifice diameter 15cm is inserted in pipe of 30m diameter. The pressure difference measured by a mercury oil differential manometer on the two sides of the orifice meter gives a reading of 50cm of mercury. Find the rate of flow of oil of specific gravity 0.9 when the
co-efficient of discharge of the meter=0.64. [7M]
UNIT – IV
7. (a) Derive an expression for displacement thickness due to formation of boundary layer. [7M]
(b) Air is flowing over a smooth plate with a velocity of 10m/sec. The length of the plate is 1.2m and width 0.8m. If laminar boundary layer exists up to a value of Re= 2X105 , find the maximum distance from the leading edge up to which laminar boundary layer exists. Find the maximum thickness of laminar boundary layer if the velocity profile is given by, u/U = 2(y/δ)−(y/δ)2.
Take kinematic viscosity for air=0.15 stokes. [7M]
8. (a) What do you understand by separation of boundary layer? How it affects the flow pattern.[7M]
(b) For the velocity profile for laminar boundary layer flow given asu/U = 2(y/δ)−(y/δ)2. Find an expression for boundary layer thickness (δ), shear stress. [7M]
UNIT – V
9. (a) Derive an expression for loss of head due to friction in pipes. [7M]
(b) Determine the wall shearing stress in a pipe of diameter 100 mm, which carries water. The velocities at the pipe centre and at 30mm from the centre of the pipe is 2m/s and 1.5m/s
respectively. [7M]
10. (a) Explain the significance of major and minor losses in pipes. What are the general formulae to
determine minor losses? [7M]
(b) A crude oil of kinematic viscosity 0.4 stokes is flowing through a pipe diameter 300 mm at the rate of 300 litres per second. Find the head loss due to friction for a length of 50m of the pipe.
[7M]
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Hall Ticket No Question Paper Code: ACE005
INSTITUTE OF AERONAUTICAL ENGINEERING
(Autonomous)
B.Tech IV Semester End Examinations ( Supplementary) - May, 2018 Regulation: IARE – R16
FLUID MECHANICS
Time: 3 Hours (CE) 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. (a) Derive the equation for centre of pressure of an inclined plane surface submerges in a liquid.
[7M]
(b) An oil of viscosity 5 poise is used for lubrication between a shaft and sleeve. The diameter of the shaft is 0.5 m and it rotates at 200 rpm. Calculate the power lost in oil for a sleeve length of 100
mm. Assume the thickness of oil film is 1.0 mm. [7M]
2. (a) Explain about micro manometers with a neat sketch and derive the expression for pressure dif-
ference between two points using micro manometers. [7M]
(b) Determine the total pressure and center of pressure of an isosceles triangular plate of base 4 m and altitude 4 m when immersed vertically in an oil of specific gravity 0.9. The base of the plate
coincides with the free surface of oil. [7M]
UNIT – II
3. (a) Derive continuity equation in three-dimensional flow. [7M]
(b) Derive the equation of stream function and velocity potential for a uniform stream of velocity(V) in a two-dimensional field, the velocity(V) being inclined to the X-axis at a positive angleα.
[7M]
4. (a) Define total acceleration, convective acceleration and local acceleration. [7M]
(b) Does the velocity potential exist for two dimensional incompressible flow prescribed by u = x-4y;
v = -(y+4x). If so, determine velocity potential function and stream function. [7M]
UNIT – III
5. (a) State the momentum equation. How will you apply momentum equation for determining the
force exerted by a flowing fluid on a pipe bend? [7M]
(b) The head of water over an orifice of diameter 100mm is 10m. The water coming out from orifice is collected in a circular tank of diameter 1.5m. The rise of water level in this tank is 1.0 m in 25 seconds. Also the coordinates of a point on the jet, measured from vena-contracta are 4.3 m horizontal and 0.5 m vertical. Find the coefficients Cd,Cc and Cv. [7M]
6. (a) Derive Euler’s equation of motion. How will you obtain Bernoulli’s expression from it? [7M]
(b) Find the discharge through a trapezoidal notch which is 1 m wide at the top and 0.4 m at the bottom and is 30 cm in height. The head of water on the notch is 20 cm. Assume Cd for rectangular portion as 0.62 while for triangular portion as 0.6. [7M]
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UNIT – IV
7. (a) What are the different methods of preventing the separations of the boundary layers? Explain any two methods in detail to control separation with a neat sketch. [7M]
(b) An open rectangular box 20m x 3m x 1.5m is drawn longitudinally through water at a velocity of 10 m/s. Determine the drag force. Takeγ = 1X10−6m2/sand ρ= 1000kg/m3. [7M]
8. (a) Define: boundary layer, boundary layer thickness, drag, lift and momentum thickness. [7M]
(b) Discuss magnus effect in boundary layer theory and explain in detail two applications of magnus
effect. [7M]
UNIT – V
9. (a) Derive Darcy-weisbach equation for determination of head loss in pipes. [7M]
(b) A main pipe line divides into two parallel pipes which again forms one pipe. The length and diameter for the first parallel pipe are 2000m and 1m respectively, while the length and diameter for second parallel pipe are 2000m and 0.8m respectively. Find the rate of flow in each parallel line, if total flow in the main is 5m3/s. The coefficient of friction for each pipe is same and equal
to 0.004. [7M]
10. (a) Explain about Reynold’s experiment to determine type of flow. Classify the different types of
flows based on it. [7M]
(b) An oil of specific gravity 0.9 and viscosity 0.06 poise is flowing through a pipe of diameter 200mm at the rate of 60 liters/s. Find the head lost due to friction for a 500 m length of pipe. Find the
power required to maintain this flow. [7M]
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