Summer 2015 Power Plant Engineering Question Paper

***************

GUJARAT TECHNOLOGICAL UNIVERSITY
DIPLOMA ENGINEERING – SEMESTER – VI • EXAMINATION – SUMMER 2015
Subject Code: 3361906  Date:11-05-2015
Subject Name: Power Plant Engineering
Time: 10:30am to 1:00pm            Total Marks: 70

Instructions:
1.  Attempt all questions.
2.  Make Suitable assumptions wherever necessary.
3.  Figures to the right indicate full marks.
4.  Use of programmable & Communication aids are strictly prohibited.
5.  Use of only simple calculator is permitted in Mathematics.
6.  English version is authentic.
7.  Use of steam table and molliar chart are permissible.

***************

Q.1 Answer any seven out of ten.   14

1.  Write the basic elements of various power plants.

2.  Give the function of trace rack in hydro power plant.

3.  Define binding energy.

4.  Write name of any three high pressure boilers.

5.  Write the function of ESP in steam power plant.

6.  Classify control system of steam power plant.

7.  Write down the auxiliary system of gas turbine power plant.

8.  Define cut in speed for wind turbine.

9.  Define load curve and load factor.

10.  What is tariff?

Q.2  (a)  Give the advantages of high pressure boiler.  03

OR

(a)  Explain reheat rankine cycle with h-s and t-s diagram.   03

(b)  Define air pre-heater and explain any one type of air pre-heater with sketch.  0 3

OR

(b)  State the functions of basic elements of control system.  03

(c)  Give the uses of diesel engine power plant.  04

OR

(c)  Explain with neat sketch cooling system of a diesel engine power plant.   04

(d)  Explain working of PWR with neat sketch.  04

OR

(d)  Write short note on disposal of nuclear waste.    04

Q.3  (a)  Explain Benson boiler with neat sketch.  03

OR

(a)  Define pulverized fuel supply system and explain any one.  03

(b)  List the instruments used to measure various parameters in modern central control room.  03

OR

(b)  Write short note on open loop control system.  03

(c)  In a steam power plant working on simple rankine cycle, the boiler pressure and condenser pressure are 35 bar and 0.1 bar respectively. If temperature of steam entering to turbine is 350 ⁰C, calculate (i) efficiency of rankine cycleand (ii) specific steam consumption.  04

OR

(c)  Explain fluidized bed combustion boilers.  04

(d)  Explain effects of load variation on various parameters of steam power plant.  04

OR

(d)  State the purpose of various records maintained in steam power plant.   04

Q.4  (a)  Compare gas turbine with diesel engine as prime mover.  03

OR

(a)  List the advantages of closed cycle gas turbine plant.  03

(b)  Draw the schematic diagram of modern thermal power plant.  04

OR

(b)  List the methods used to increase the efficiency of rankine cycle. Discuss any one from them.  04

(c)  A gas turbine plant is working on brayton cycle. Air enters the compressor at 15 ⁰C and 1 bar pressure. Pressure ratio is 6, air is then heated in combustion chamber where it is heated up to 727 ⁰C. Then this air is expanded in theturbine to a pressure of 1 bar. If the temperature at the end of compression is 242 ⁰C and at the outlet of the turbine is 366 ⁰C, then find out the isentropic efficiency of compressor & turbine. Take Cp =1.005 KJ/ Kg K and γ =1.4.   07

Q.5  (a)  Derive the relation between wind velocity, air mass and wind power for wind energy power plant.  04

(b)  Explain solar module and solar array.  04

(c)  Define: (1) connected load (2) demand factor (3) plant capacity factor 03

(d)  Explain fixed cost and operating cost of power plant.  03

***************