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arXiv · 2606.16314

Endoreversible Carnot machines with long-time reversible limit

Ramandeep S. Johal·Rajeshree Chakraborty
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Abstract

The well-known Curzon-Ahlborn (CA) engine [Am. J. Phys. {\bf 43}, 22 (1975)] runs in finite time and yields a finite power output. In order to recover the standard Carnot cycle from the CA model, the limit of quasi-static operation has to be concurrent with the reversible limit, a condition strangely missing from the CA model. We augment this model by specifying the duration of the isothermal process as a monotonic decreasing function of the temperature difference between the working substance and the reservoir. As an illustration, we analyze the machine's operation in the low-dissipation regime in which the entropy production in each isothermal branch is inversely proportional to the duration of the process. The modified model is able to determine the optimal durations of isothermal processes as well as heat and work per cycle, while retaining the optimal power conditions of the CA model.

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Ramandeep S. Johal, Rajeshree Chakraborty. 2026-06-15. Endoreversible Carnot machines with long-time reversible limit. https://arxiv.org/abs/2606.16314

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