Abstract: | Maximum power output of a class of irreversible non-regeneration heat engines with non-uniform working fluid, in which heat
transfers between the working fluid and the heat reservoirs obey the linear phenomenological heat transfer law q ∝ Δ(T
−1)], are studied in this paper. Optimal control theory is used to determine the upper bounds of power of the heat engine for
the lumped-parameter model and the distributed-parameter model, respectively. The results show that the maximum power output
of the heat engine in the distributed-parameter model is less than or equal to that in the lumped-parameter model, which could
provide more realistic guidelines for real heat engines. Analytical solutions of the maximum power output are obtained for
the irreversible heat engines working between constant temperature reservoirs. For the irreversible heat engine operating
between variable temperature reservoirs, a numerical example for the lumped-parameter model is provided by numerical calculation.
The effects of changes of reservoir’s temperature on the maximum power of the heat engine are analyzed. The obtained results
are, in addition, compared with those obtained with Newtonian heat transfer law q ∝ Δ(T)]. |