ENDOREVERSIBLE THERMAL CYCLE WITH A NONLINEAR HEAT-TRANSFER LAW

We calculate the efficiency of an endoreversible Carnot-type cycle in the maximum power regime by using a nonlinear heat transfer law (the s o-called Dulong and Petit's law of cooling). The results obtained from this model compare well (around 99% in some cases) with observed effi ciencies for several power plants. The considered law of cooling inclu des conductive-convective and radiative contributions to the heat exch ange between the working fluid and its surroundings. Our calculations improve considerably those obtained by means of a linear heat transfer law for the same power sources. We also analyze a nuclear power plant using an ecological optimization criterion for finite-time heat engin es.