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arXiv · 0907.4868

Onsager coefficients of a finite-time Carnot cycle

Yuki Izumida·Koji Okuda
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Abstract

We study a finite-time Carnot cycle of a weakly interacting gas which we can regard as a nearly ideal gas in the limit of $T_\mathrm{h}-T_\mathrm{c}\to 0$ where $T_\mathrm{h}$ and $T_\mathrm{c}$ are the temperatures of the hot and cold heat reservoirs, respectively. In this limit, we can assume that the cycle is working in the linear-response regime and can calculate the Onsager coefficients of this cycle analytically using the elementary molecular kinetic theory. We reveal that these Onsager coefficients satisfy the so-called tight-coupling condition and this fact explains why the efficiency at the maximal power $\eta_\mathrm{max}$ of this cycle can attain the Curzon-Ahlborn efficiency from the viewpoint of the linear-response theory.

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Yuki Izumida, Koji Okuda. 2009-07-28. Onsager coefficients of a finite-time Carnot cycle. https://doi.org/10.1103/physreve.80.021121

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