A variational ecological-type optimization of some thermal-engine models

In a recent work [23] we have analyzed a nonendoreversible thermal engine model under two maximization criteria: the maximum power regime and the so-called ecological criterion. In the present work, we extend the study of the same class of nonendoreversible models, but by using the so-named generalized ecological criterion [15]. This criterion is based on a family of ecological-type functions depending on a parameter associated to the particular heat transfer law used in the engine model. By means of this criterion we find a simplification of some of the results obtained in [23] by using both conventional and variational calculus. Besides, we propose a simple procedure to calculate the parameter involved in the generalized ecological function.