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arXiv · 1612.07922

True nature of the Curzon-Ahlborn efficiency

Yann Apertet·Henni Ouerdane·Christophe Goupil·Philippe Lecoeur
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Abstract

The Curzon-Ahlborn efficiency has long served as the definite upper bound for the thermal efficiency at maximum output power, and has thus shaped the development of finite-time thermodynamics. In this paper, we repeal the ruling consensus according to which it has a genuine universal character that can be derived from linear irreversible thermodynamics. We demonstrate that the Curzon-Ahlborn efficiency should instead properly be associated with a particular case of nonlinear heat engines, and we derive a generalized expression for the efficiency at maximum power beyond the restrictive case of linear models.

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Yann Apertet, Henni Ouerdane, Christophe Goupil, Philippe Lecoeur. 2017-08-10. True nature of the Curzon-Ahlborn efficiency. https://doi.org/10.1103/physreve.96.022119

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