An eight-cylinder four-stroke eight-litre Diesel engine runs at 2000rpm. The engine operation is to be analysed...

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An eight-cylinder four-stroke eight-litre Diesel engine runs at 2000rpm. The engine operation is to be analysed using the following simplifying assumptions: i. ii. iii. iv. V. vi. vii. At the start of the compression stroke the cylinder already contains the fuel and air mixture at 1bar and 300K; Compression is isentropic with a volume ratio of 18; Combustion is an adiabatic constant pressure process. The gravimetric air- fuel ratio is 40, and the lower calorific value of the fuel is 42MJ/kg; The rest of the expansion stroke is isentropic; There are no pumping losses; The mechanical efficiency of the engine is 85%; The fluid in the cylinder is a perfect gas with constant cp = 1.2kJ.kg-¹.K-1 and R = 0.287kJ.kg-1.K-1 throughout the engine cycle. Calculate the following quantities: a) The pressure at the end of the compression stroke b) The maximum and minimum volumes of one cylinder c) The temperature at the end of combustion d) The cut-off ratio e) The indicated power output of the engine f) The indicated mean effective pressure g) The indicted efficiency h) The brake power output i) The brake specific fuel consumption. An eight-cylinder four-stroke eight-litre Diesel engine runs at 2000rpm. The engine operation is to be analysed using the following simplifying assumptions: i. ii. iii. iv. V. vi. vii. At the start of the compression stroke the cylinder already contains the fuel and air mixture at 1bar and 300K; Compression is isentropic with a volume ratio of 18; Combustion is an adiabatic constant pressure process. The gravimetric air- fuel ratio is 40, and the lower calorific value of the fuel is 42MJ/kg; The rest of the expansion stroke is isentropic; There are no pumping losses; The mechanical efficiency of the engine is 85%; The fluid in the cylinder is a perfect gas with constant cp = 1.2kJ.kg-¹.K-1 and R = 0.287kJ.kg-1.K-1 throughout the engine cycle. Calculate the following quantities: a) The pressure at the end of the compression stroke b) The maximum and minimum volumes of one cylinder c) The temperature at the end of combustion d) The cut-off ratio e) The indicated power output of the engine f) The indicated mean effective pressure g) The indicted efficiency h) The brake power output i) The brake specific fuel consumption.

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