Abstract: The weak-dissipation assumption is used to the model of a class of generalized Carnot heat engine cycles composed of two adiabatic and two polytropic processes, from which the expressions for the power output and efficiency of these cycles are derived. The lower and upper efficiency bounds of these cycles at the maximum power output are determined and the performance characteristics of these cycles are discussed.

Key words: generalized Carnot heat engine, irreversible loss, weak-dissipation assumption, performance characteristic