Thermal Exergy Optimization of an Irreversible Cogeneration Cycle
This paper investigates the cogeneration system coupled with external heat reservoir of finite heat capacity and
including both external irreversibility and internal irreversibility due to the finite-rate heat transfer between the working fluid
and heat reservoirs and due to heat dissipation of working fluid respectively. The effect of operating inlet and outlet
temperature, heat capacitance rate of external fluid, effectiveness of source/sink side heat exchanger and internal
irreversibility parameter and temperature ranges of reservoir on the design parameter of cogeneration cycle has been included.
The presence of both the irreversibility parameters shows that a cogeneration power plant with irreversibility delivers less
exergy output and has a lower efficiency as compared to reversible cycles. The model presented here is of more use when
compared to those obtained by earlier researchers. The effect of the heat consumer temperature parameter (Ψ) & extreme
temperature ratio (Φ) on the maximum total exergy rate and the corresponding exergy efficiency are investigated. The results
are plotted in graphs with considering various parameters.
Index Terms — Cogeneration, Exergy, Endoreversible, Combined Heat And Power.