Calculate the Indicated Power, Brake Power and Mechanical efficiency of the engine.

Question

The following set of observations refer to a trial on a Single-cylinder, Four-stroke, Solid injection diesel engine of 200 mm bore and 400 mm stroke?

Gross mean effective pressure                                = 6.2 bar

Pumping mean effective pressure                           = 0.44 bar

Speed of the engine                                               = 262 rpm

Brake torque                                                          = 668 N-m

Fuel supply rate                                                     = 4.5 kg/hr

Calorific value of the fuel                                      = 52,000 kJ/kg

Cooling water flow rate                                          = 6 kg/min

Cooling water temperature gain                             = 47⁰C

Calculate the Indicated Power, Brake Power and Mechanical efficiency of the engine.

Draw up a heat balance sheet for the trial expressing various quantitie in kJ/min, if he fuel contains 13.5%H₂ (by mass) and air supply to the engine is 2.71 kg/min at 17⁰C. The exhaust gases leave the engine at 400⁰C. The following data may be used:

Mean specific heat of exhaust gases                       = 1 kJ/kgK

Specific heat of steam                                            = 2.1 kJ/kgK

Latent heat of steam                                               = 2250 kJ/kg

Estimate the heat carried away by steam in exhaust gases.