Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Winter 5th Sem 2151903 Fluid Power Engineering Previous Question Paper
Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE- SEMESTER?V (NEW) EXAMINATION ? WINTER 2020
Subject Code:2151903 Date:03/02/2021
Subject Name:Fluid Power Engineering
Time:10:30 AM TO 12:30 PM Total Marks: 56
Instructions:
1. Attempt any FOUR questions out of EIGHT questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1 (a) Draw general layout of hydro power plant with essential components.
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(b) Classify hydro power plant
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(c) Derive expression of work done for impact of jet on a moving inclined
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plate.
Q.2 (a) Explain principle of jet propulsion
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(b) Obtain expression for the efficiency and maximum efficiency of jet
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propulsion when inlet orifices are at right angle to ship.
(c) A jet of water impinges on a symmetrically curved vane at the centre. The
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velocity of the jet is 60 m/sec and the diameter is 120 mm. The jet is
deflected through an angle of 120?. Calculate the force on the vane if the
vane is fixed. Also determine the force if the vane moves with a velocity of
25 m/sec in the direction of jet. What will be the power and efficiency?
Q.3 (a) Differentiate between impulse and reaction hydraulic turbines.
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(b) Explain with neat sketch the functions of main components of Pelton
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turbine.
(c) A Pelton wheel is required to develop 4000 kW at 400 rev/min, operating
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under net head of 350 m. There are two jets and the bucket deflection angle
is 165?. Calculate the bucket pitch circle diameter, the cross sectional area
of each jet and the hydraulic efficiency of the turbine. Make the following
assumptions (i) overall efficiency is 85% when the water is discharged
from the wheel in a direction parallel to the axis of rotation(ii) Co-efficient
of velocity of nozzle Kv=0.97 and the blade speed ratio Ku=0.46(iii)
relative velocity of water at exit from the bucket is 0.86 times the relative
velocity at inlet.
Q.4 (a) Compare Francis and Kaplan Turbine
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(b) Derive the equation of hydraulic efficiency of a Pelton turbine. Obtain
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condition for maximum hydraulic efficiency.
(c) A reaction turbine works at 450 rpm under a head of 120 m. Its diameter at
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inlet is 120 cm and the flow area is 0.4 m2. The angle made by absolute and
the relative velocity at inlet are 20? and 60? respectively with a tangential
velocity. Determine: (i) volume flow rate. (ii) power developed (iii)
hydraulic efficiency.
Q.5 (a) What is pump? Classify Pumps.
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(b) What is cavitation? What are its effects?
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(c) The impeller of a centrifugal pump has an external diameter of 450 mm and
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internal diameter of 200 mm and it runs at 1440 rpm. Assuming a constant
flow velocity through the impeller at 2.5 m/s and that the vanes at the exit
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are set back at angle of 25?. Determine (i) Inlet vane angle (ii) The angle,
absolute velocity of water makes with the tangent at the exit and (iii) The
work done per unit weight of water.
Q.6 (a) Define and derive specific speed relation for pump.
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(b) Explain submersible pump with advantages and disadvantages
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(c) Write down difference between Positive displacement pumps and
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Rotodynamic pumps.
Q.7 (a) Draw a neat sketch, and explain the operation of Hydraulic Accumulator.
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(b) What is pre-whirl? Explain the effect of Pre-whirl in centrifugal
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compressor.
(c) Explain the effect of blade shape of impellers on performance of
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Centrifugal compressor. Also classify the blades based on curvature.
Q.8 (a) Draw a neat sketch, and explain the operation of Hydraulic Crane.
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(b) Give comparison between axial flow and centrifugal compressor
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(c) A centrifugal compressor running at 12000 rpm delivers 1.3 m3/s of free
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air. The pressure and temperature at inlet are 1 bar and 25?C. The
compression ratio is 5, blades are radial at outlet, the velocity of flow is 58
m/s and is constant throughout. Assume slip factor is 0.9 and isentropic
efficiency is 84 % . Determine (i) temperature of air at outlet, (ii) impeller
diameter and blade angle at inlet and (iii) power required. Assume inlet
diameter of impeller half of outlet diameter of impeller
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This post was last modified on 04 March 2021