Optimal thermodynamics new upperbounds

We propose here a review of what has been published, by numerous authors, showing the ideas evolution since the pioneering of S. Carnot, and particularly, the coupling of thermostatics with thermokinetics (heat and mass transfers) through the papers proposed simultaneously by P. Chambadal and I. Novikov in 1957. Since that time, the great majority of works is related to thermomechanical machines, with various cycles (Joule-Brayton; Otto Beau de Rochas; Diesel; Stirling; Ericson are the most studied), the reference cycle remaining the Carnot one. We propose here to reconsider these approaches from a lumped point of view. It appears that the two main influences could be represented by two parameters: - Si, the created entropy rate inside the machine, with the hypothesis of a stationary state analysis, or I the irreversibility ratio. - Kl, the heat loss conductance of the system (including the machine, and heat source and sink) between the hot spot TSH and cold spot TSL of the system, at the same functioning conditions. As a conclusion is reported the challenge to continue to develop the proposed concepts and methodology (optimal thermodynamics) and apply them to determinate general upperbounds of specific applications and systems in order they have a better energy efficiency and durability and to validated the methodology by comparison with experimental results. (author)