Comparison of Performances of Air-Standard Atkinson, Diesel and Otto Cycles with Constant Specific Heats

The current paper examines the application of finite-time thermodynamics in order to compare the performance between air-standard cycles, i.e. Atkinson, Diesel and Otto cycles with constant specific heats of working fluid. The effects of input temperature and compression ratio on the net output work and efficiency of the Atkinson cycle, Diesel cycle and Otto cycle are analyzed. It is assumed that the compression and power processes are isentropic and any convective, conductive and radiative heat transfer to cylinder wall during the heat rejection process may be ignored. The efficiency of these cycles is compared for equal maximum temperature as well. The findings may present guidance concerning performance evaluation and improvement of practical internal combustion engines.