the higher efficiency? Q3: A 4-stroke, 6-cylinders diesel engine have a bore of 11 cm and a stroke of 13 cm for each cylinder. The brake torque is 153 N.m, engine speed is 2250 rpm, fuel consumption is 0.00283 kg/s, calorific value of fuel is 43000 kJ/kg, and the air-fuel ratio (AFR) is 28.4:1. If the atmospheric conditions are 15 C and 100 kPa, find the following: 1-brake power, 2-brake thermal efficiency, 3-brake mean effective pressure, 4-volumetric efficiency.