GUJARAT TECHNOLOGICAL UNIVERSITY
BE - SEMESTER-VII (NEW) EXAMINATION — WINTER 2018
--- Content provided by FirstRanker.com ---
Subject Code: 2171910 Date: 06/12/2018
Subject Name: Power Plant Engineering
Time: 10:30 AM TO 01:00 PM Total Marks: 70
Instructions:
- Attempt all questions.
- Make suitable assumptions wherever necessary.
- Figures to the right indicate full marks.
- Use of Mollier chart and steam table is permissible.
--- Content provided by FirstRanker.com ---
Q.1 (a) Explain the function of following equipments in a thermal power plant : 03
Reheater, control room and air-preheater.
--- Content provided by FirstRanker.com ---
(b) Explain the principle of fluidized bed combustion. 04(c) Name two indirectly heated high pressure boilers and explain construction and 07
working of any one of them.
Q.2 (a) What are the requirements of a good ash handling plant. 03
(b) Describe the unit pulverized coal handling system. 04
--- Content provided by FirstRanker.com ---
(c) Explain cyclone burner with neat diagram. 07OR
(c) Write a short note on electrostatic precipitator. 07
Q.3 (a) Derive the expression for the velocity in terms of enthalpy drop for a flow 03
through the nozzle.
--- Content provided by FirstRanker.com ---
(b) With a neat diagram explain balanced -draught. Also explain pressure 04distribution in balanced draught.
(c) Steam at a pressure of 15 bar and dryness fraction 0.95 is discharged through a 07
convergent-divergent nozzle to a back‘pressure of 0.5 bar. The mass flow rate is
9 kg/kwhr. If the power developed is 200 kW, determine :
--- Content provided by FirstRanker.com ---
(i) Throat pressure(ii) Number of nozzles required if each nozzle has a throat of
rectangular cross-section of 4 mm x 8 mm.
(iii) If 10% of overall isentropic enthalpy drop reheats by friction
the steam in divergent portion, find the cross-section of the
--- Content provided by FirstRanker.com ---
exit rectangleOR
(a) Explain the principle of operation of steam turbine. 03
(b) Differentiate between forced and induced draft. 04
(c) A single row impulse turbine develops 135 kW at a blade speed of 180 m/sec 07
--- Content provided by FirstRanker.com ---
using 2 kg of steam per second. Steam leaves the nozzle at 400 m/sec. Velocitycoefficient of the blades is 0.9. Steam leaves the turbine blades axially.
Determine
(i) Nozzle angle
(ii) Blade angles at entry and exit assuming no shock.
--- Content provided by FirstRanker.com ---
Q.4 (a) Explain the working principle of plain Labyrinth glands used in steam turbine. 03
(b) Explain downflow surface condenser. 04
OR
(a) What are the sources of air leakage in a condenser ? 03
(b) Write a note on fast breeder reactor. 04
--- Content provided by FirstRanker.com ---
(c) Differentiate between nuclear fusion and fission. 07Q.5 (a) What is the need of cooling gas turbine blades ? Explain transpiration cooling 03
of gas turbine blades.
(b) What do you mean by thrust augmentation ? State the methods for thrust 04
augmentation in a turbojet engine and discuss any one of them.
--- Content provided by FirstRanker.com ---
(c) A gas turbine operates on Brayton cycle. The temperature range is 1050 K and 07288 K. Find pressure ratio for maximum power output. Also determine thermal
efficiency, work ratio and power output, if the mass flow rate of air is 20 kg/sec.
Take Cp = 1.005 kJ/kg K and y = 1.4 for compression and expansion process.
OR
--- Content provided by FirstRanker.com ---
(a) State classification of rocket engines. 03(b) State the advantages of combined gas and steam power plant. 04
(c) What do you understand by the term tariff ? State the various methods for 07
calculation of tariff and discuss any three of them.
--- Content provided by FirstRanker.com ---
This download link is referred from the post: GTU BE/B.Tech 2018 Winter Question Papers || Gujarat Technological University
--- Content provided by FirstRanker.com ---