Alireza Hajipour - Department of Mechanical Engineering, University of Islamic Azad University, Science and Research branch, Boroujerd, Iran. And Department of Mechanical Engineering, Young Researchers Club, Ayatollah Amoli branch, Islamic Azad University,

In this paper, the effects of input temperature and compression ratio on the net output work and efficiency of the air standard cycles, i.e. Atkinson cycle, Diesel cycle and Otto cycle are analyzed. We assumed that the compression and power processes are adiabatic and reversible and any convective, conductive and radiative heat transfer to cylinder wall during the heat rejection process may be ignored. We compared efficiency of these cycles with constant maximum temperature of each cycle. The results of this comparison may provide guidance for performance evaluation and improvement of practical internal combustion engines.