Exergy optimization for an irreversible combined cogeneration cycle

Exergy optimization is presented for an irreversible combined cogeneration cycle which includes three types of irreversibilities: finite rate heat transfer, heat leakage and internal irreversibility. The optimal design conditions at maximum exergy output and maximum exergy efficiency output were determined. The effects of the internal irreversibility, heat leakage and heat to power ratio on the exergetic performance are investigated and the results are discussed. It is shown that the optimal exergetic performance intervals stay approximately constant with power to process heat ratio, but they decrease with irreversibility parameter.