Classify the Babcock-Wilcox boiler. What is the function of a superheater?
[3 marks]Describe advantages and disadvantages of solar energy.
[4 marks](i) A 3-kg plastic tank that has a volume of 0.2 m3 is filled with liquid water. Determine the weight of the combined system. (ii) Apressure gage connected to a tank reads 500 kPa at a location where the atmospheric pressure is 94 kPa. Determine the absolute pressure in the tank. (iii) What is the characteristic of a steady-flow process?
[7 marks]State the function of any three accessories in boilers.
[3 marks]What is the difference between elasticity and plasticity? What do you understand by resilience?
[4 marks]Air enters a compressor at 1.013 bar and 27oC having a volume of 5 m3/kg and it is compressed to 12 bar isothermally. Determine: (i) work done, (ii) heat transfer, and (iii) change in internal energy.
[7 marks]Five kg of air is heated from an initial volume of 0.5 m3 to final volume of 1.3 m3 at constant pressure 4 bar. Determine: (i) heat supplied, (ii) work done, and (iii) initial and final temperature of air. C = 1.005 kJ/kg K, R = 0.287 kJ/kg K. p
[7 marks]Draw a schematic diagram of a differential bank brake.
[3 marks]Show the vapour compression refrigeration cycle on T-s and p-h diagram. Name each process in the cycle.
[4 marks]Steam at 5 bar and dryness fraction of 0.85 expands reversibly at constant pressure until the temperature is 220oC. Determine the work and heat transfer per kg of steam during the process. Take specific heat for superheated steam as 2.1 kJ/kg K.
[7 marks]Page 1 of
[2 marks]Answer in one word:
[3 marks]Which coupling is used to connect engine shaft to driven shaft in automobile? (ii) Energy absorbed by a brake is released into the environment in the form of which energy? (iii) What causes the outward movement of a shoe in centrifugal clutch?
[ marks]Aclassroom has a window air conditioner of 2 TR capacity. Its COP is 3. How much electrical energy (in kWhr) will be consumed in one month if the unit runs for 6 hours per day?
What is a flexible coupling? What are its types?
[3 marks]Draw a diagram of vortex-type centrifugal pump.
[4 marks]Asteam plant works on ideal Rankine cycle. Steam is supplied at 25 bar and 290oC. The steam exhausts into a condenser at 15 kN/m2 with 0.9 dry. Determine the cycle efficiency.
[7 marks]Give similarities and differences between a friction clutch and a positive-contact clutch.
[3 marks]Describe in short the parts of a reciprocating pump.
[4 marks]An oil engine working on diesel cycle has cylinder bore of 190 mm and piston stroke of 230 mm. The clearance volume is 290 cm3. The fuel injection takes place at a constant pressure for 6% of the stroke. Determine the air-standard efficiency.
[7 marks]Answer in short:
[3 marks]Name the different types of belt drives. (ii) Enlist different gear types. (iii) Give one benefit of using a V-belt.
[ marks]What do you understand by positive displacement compressor? How it differs from rotodynamic compressor?
[4 marks]Explain following terms of I.C. engine: (i) brake power, (ii) indicated power, (iii) specific fuel consumption, (iv) clearance volume.
[7 marks]State one disadvantage of rope drive, chain drive and gear drive.
[3 marks]Define with regard to compressors: double-acting compressor, multistage compressor, displacement (swept) volume, pressure ratio.
[4 marks]A 6-cylinder 4-stroke I.C. engine is used to produce 95 kW brake power at 800 rpm. The stroke to bore ratio is 1.25. Mean effective pressure is 7 bar. Determine the bore and stroke of the engine. Assume mechanical efficiency as 80%. Page 2 of
During a test of steam with throttling calorimeter, sample is taken from main pipe at 15 bar, pressure and temperature after throttling are 1.2 bar and 150oC respectively. Determine dryness fraction of steam. Take specific heat of superheated steam as 2.1 kJ/kg K.
[7 marks]