Answer to Question #308320 in Mechanical Engineering for Natoy

Question

At the beginning of compression in an ideal air standard Diesel cycle, the compression ratio is 16 with p1 = 100 kPa and T1= 300K. The maximum temperature of the cycle is 2000K. If cp = 1.005 kJ/ kgm-K and cv= 0.718- kJ/kgm-°K for the air, compute (a) the pressure, temperature and volume at four corners of the cycle. (b) the heat transfer (c) the work done per kgm for each process, and (d) the cycle thermal efficiency.

Answer 1

In the theoretical Diesel cycle analysis concerning combustion and heat transfer effects, the more the heat transfer decreases, the more the energy lost to the exhaust increases even though the work output and the thermal efficiency increase.

The thermal efficiency, η_th, represents the fraction of heat, Q_H, converted to work.