266 POWER PLANT ENGINEERING
Calorific value of fuel = 42000 kJ/kg
Brake mean effective pressure = 6.0 bar
Net load on brakes = 1500 N
r.p.m. = 300, brake drum diameter = 1.8 m
Brake rope diameter = 20 mm
Quantity of jacket cooling water = 600 kg
Temperature rise of jacket water = 55°C
Quantity of air as measured = 250 kg
Exhaust gas temperature = 420°C
CP for exhaust gases = 1 kJ/kg K
Ambient temperature = 20°C.
Calculate: (i) Indicated power; (ii) Brake power; (iii) Mechanical efficiency; (iv) Indicated
thermal efficiency.
Draw up a heat balance sheet on minute basis.
[Ans. (i) 47.7 kW, (ii) 42.9 kW, (iii) 89.9%, (iv) 35.86°b]