Elements of Mechanical Engineering — Summer 2023

Explain the following terms in brief: (1)Heat and work (2)Specific heat and calorific value of fuel (3)Differentiate between vapor and gas (4)List various source of energy

Define Zeroth law, First law and Second law of thermodynamics. Give limitations of first law of thermodynamics

Sketch the Cochran boiler and label all important mountings and accessories

State the function of (i) Fusible Plug (ii) Economiser (iii) Safety valves (iv) water level indicator (v) Superheater (vi) Pressure gauge (vii) Air pre-heater

Write short note on all types of belt drive.

Define the following terms related to belt drive: (i) Velocity ratio (ii) Initial Tension (iii) Slip (iv) Creep (v) Power transmitted in belt drive

Explain with neat sketch split air conditioner. State its advantages.

Classify the air compressor. Differentiate between reciprocating compressor and rotary compressor.

With the help of neat sketch the working of four stroke diesel engine.

Following readings were taken during test of single cylinder four stoke oil engine. (i) Cylinder diameter = 250 mm (ii) Stroke length = 400 mm (iii) Main effective pressure = 7 bar (iv) Engine speed = 250 r. p .m. (v) Net load on brake = 1080 Newton (vi) Effective diameter of brake = 1.5 meter (vii) Fuel used per hour = 10 Kg (viii) Calorific value of fuel = 44300 KJ/Kg Calculate (1) Indicated power, (2) Brake power, (3) Mechanical efficiency and (4) Indicated thermal efficiency.

What is Adiabatic process? Prove with usual notations the governing equation for adiabatic process PVγ = Constant

Five kg of air is heated from initial volume of 0.5 m3 to final volume of 1.3 m3 at constant pressure 4 bar. Determine (1) heat supplied (2) work done (3) initial and final temperature of air. Take Cp=1.005 KJ/kg-Kand R=0.287 KJ/kg-K

Discuss Watt Governor and Porter Governor in detail

Define following mechanical properties (1)Elasticity (2)Malleability (3)Ductility (4)Impact strength (5)Hardness (6)Toughness (7) Resilience.