Question Paper: Power Plant Engineering : Question Paper Dec 2014 - Mechanical Engineering (Semester 7) | Mumbai University (MU)
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## Power Plant Engineering - Dec 2014

### Mechanical Engineering (Semester 7)

TOTAL MARKS: 80
TOTAL TIME: 3 HOURS
(1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Assume data if required.
(4) Figures to the right indicate full marks.

### Write short notes on any four of the following

1 (a) Load management of power plant(10 marks) 1 (b) Benefits of co-generation(10 marks) 1 (c) Mechanical dust collectors(10 marks) 1 (d) Surge tank(10 marks) 1 (e) Cooling system for diesel power plant.(10 marks) 1 (f) Water hammer and its remedial measures(10 marks) 2 (a) Prove that the condition for economic loading of different units for a power [10] plant site is dl1/dL1=dI2=dI3/dL3=-----dIn/dLn(10 marks) 2 (b) A 300 MW thermal power plant is to supply power to a system having maximum and minimum demand of 240 MW and mo MW respectively in a year. Assuming the load duration curve to be a straight line estimate the Load Factor and Capacity Factor of the plant.(10 marks) 3 (a) Explain with a neat sketch the operation of Pressurised Water Reactor(10 marks) 3 (b) Calculate the cost of generation per kWh for a power station having the following data:
i) installed capacity of the plant - 210 MW ii) Capital Cost : Rs.18000/kW iii)Rate of interest and depreciation = 12%. iv) Annual Load Factor = 60% v)Annual Capacity Factor = 54 % Vi) Annual Running Charges =Rs 200 × 106 vii)Energy Consulted by power plant auxiliaries - 6%. Calculate the cost of power generation per kWh and the reserve capacity.
(10 marks)
4 (a) In a regenerative gas turbine cycle the pressure ratio is 5. Air enters the compressor at 1 bar, 300 K and leaves at 490 K. The maximum temperature in the cycle is 1000K. Calculate the cycle efficiency given that effectiveness of regenerator and isentropic efficiency of the of the turbine each is 80%. Assume Cp =1.005 kJ/kgK and ratio of Specific heats is 1.4 throughout the cycle(10 marks) 4 (b) The runoff data of a river at a particular site is tabulated below:

 Month Mean Discharge (Millions of m3) Month Mean Discharge Millions of m3 January 1500 July 3000 February 1200 August 3600 March 900 September 3000 April 600 October 2400 May 300 November 2100 June 2100 December 1800

(i)Draw the hydrograph and find the mean flow.
(ii) Draw the flow duration curve
(iii) Find the power developed if the head available is 90 m and the overall efficiency of generation is 86%. Assume each month of 30 days(10 marks) 5 (a) What are the performance characteristics of a coal based thermal power plant Discuss in brief the factors to be considered for selection of site for locating the plant.(10 marks) 5 (b) In a test on a single cylinder 4 stroke diesel engine with bore 400 mm and stroke 450 mm , the following observations were made Duration of test = 1 hr; Fuel Consumption = 7.5 kg ; C.V.of fuel = 44500 kJ/kg Total revolutions-12000/hr; Mean effective Pressure = 4 Bar; Net Brake load =1500N ; Brake drum diameter = 180cm ; Rope drum diameter = 3 cm ;Jacket Cooling Water = 500 kg ; Rise in cooling water temp = 42° C :Total air consumption = .361 kg ; Exhaust gas temperature - 300°C; Room temperature = 20°C ; Specific heat of exhaust gases=1.01kJ/kgK Calculate: i) Mechanical efficiency ii) Indicated end Brake thermal efficiency iii) Draw up heat balance sheet on minute basis(10 marks) 6 (a) What are advantages Fluidised Bed Combustion. Explain with a neat sketch the operation of Circulating Fluidised Bed Boiler(10 marks) 6 (b) Discuss the effect of reheating and regeneration on the performance of Steam Power plant(10 marks) 7 (a) List the advantages of a diesel power plant(4 marks) 7 (b) Discuss in brief the disposal of radioactive waste(6 marks) 7 (c) Explain with a neat sketch any one type of Flue Gas De-sulphurization plant(10 marks)