Air Standard Cycles Air standard cycles are idealized cycles based on the following approximations: >A fixed amount of air modeled as an ideal gas is the working fluid. >The combustion process is replaced by a heat transfer from an external source. There are no exhaust and intake processes as in an actual engine. The cycle is completed by a constant-volume heat transfer process taking place while the piston is at the bottom dead center position. >All processes are internally reversible. Cold air-standard analysis >The specific heats are assumed constant at their ambient temperature values. 上游气通大学 May9,2019 3 SHANGHAI JLAO TONG UNIVERSITYMay 9, 2019 3 Air Standard Cycles Air standard cycles are idealized cycles based on the following approximations:  A fixed amount of air modeled as an ideal gas is the working fluid.  The combustion process is replaced by a heat transfer from an external source.  There are no exhaust and intake processes as in an actual engine. The cycle is completed by a constant-volume heat transfer process taking place while the piston is at the bottom dead center position.  All processes are internally reversible. Cold air-standard analysis  The specific heats are assumed constant at their ambient temperature values