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arXiv · 1907.02939

Optimal cycles for low-dissipation heat engines

Paolo Abiuso·Martí Perarnau-Llobet
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Abstract

We consider the optimization of a finite-time Carnot engine characterized by small dissipations. We bound the power with a simple inequality and show that the optimal strategy is to perform small cycles around a given working point, which can be thus chosen optimally. Remarkably, this optimal point is independent of the figure of merit combining power and efficiency that is being maximized. Furthermore, for a general class of dynamics the power output becomes proportional to the heat capacity of the working substance. Since the heat capacity can scale supra-extensively with the number of constituents of the engine, this enables us to design optimal many-body Carnot engines reaching maximum efficiency at finite power per constituent in the thermodynamic limit.

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Paolo Abiuso, Martí Perarnau-Llobet. 2020-03-05. Optimal cycles for low-dissipation heat engines. https://doi.org/10.1103/physrevlett.124.110606

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