Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Winter 7th Sem 2171910 Power Plant Engineering Previous Question Paper
Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE- SEMESTER?VII (NEW) EXAMINATION ? WINTER 2020
Subject Code:2171910 Date:02/02/2021
Subject Name:Power Plant 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.
4. Use of steam table is permitted.
MARKS
Q.1 (a) Draw general layout of thermal power plant and label various components and
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name various circuits.
(b)
Describe unique features of La-mont and Loeffler
04
boilers.
(c)
Describe compounding of steam turbine and explain pressure-velocity
07
c ompounded impulse turbine with neat sketch.
Q.2 (a) What are the difficulties encountered in ash handling.
03
(b) Develop an expression for chimney height in terms of mm of water column.
04
(c) In a constant pressure open cycle gas turbine air enters at 1 bar and 20oC and
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leaves the compressor at 5 bar. Using following data :
Temperature of gases entering the turbine-680 oC
Pressure losses in the combustion chamber- 0.1 bar
Compressor efficiency ? 85%
Turbine efficiency ? 80% ; combustion efficiency-85%
= 1.4 and Cp= 1.024 kJ/kg K for air and gas. Find
(i)
The quantity of air circulation if the plant develops 1065 kW
(ii)
Heat supplied/kg of air
(iii)
Thermal efficiency of the cycle.
Q.3 (a) What are the effects of air leakage on performance of condenser?
03
(b) Make comparison of pulverized coal firing and stoker firing.
04
(c) A Parsons reaction turbine develops 6 MW at speed of 500 rpm using 7 kg/kWh
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of steam. The exit angle of the blades are 20 o and the velocity of steam is 1.3
times the blade velocity and pressure at exit is 1.3 bar and dryness fraction is
0.92. Calculate : (i) a suitable blade height, assuming the ratio of drum diameter
to blade height is 8, and (ii) diagram power.
Q.4 (a) Define thrust, thrust power and propulsive power.
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(b) Why closed cycle is preferred over open cycle gas turbine?
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(c) Explain construction and working of cyclone burner.
07
Q.5 (a) Define super saturation, degree of under cooling and degree of super saturation
03
(b) Explain effect of load on super heater temperature.
04
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(c) A surface condenser deals with 13600 kg of steam per hour at 0.09 bar pressure.
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The steam is 0.85 dry at condensate temperature. The air extraction pipe is at
36 oC. The air leakage is 7.26 kg/hr. Determine ( i) The surface required if heat
transmission rate is 3.97kJ/cm2 per second (ii) cylinder diameter of pump for
dry air,if it is to be single acting at 60 rpm with stroke to bore ratio of 1.25 and
volumetric efficiency of 0.85.
Q.6 (a) Explain base and peak load power plants
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(b) Explain principle of reverse osmosis process.
04
(c) Write short note nuclear waste and its disposal.
07
Q.7 (a) What is sub critical and super critical boiler?
03
(b) Discuss boiling water reactor with neat sketch.
04
(c) Explain Ion exchange process with neat diagram.
07
Q.8 (a) What is the necessity of feed water treatment?
03
(b) Explain pneumatic ash handling system.
04
(c) Explain liquid metal cooled reactor with neat diagram.
07
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This post was last modified on 04 March 2021