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arXiv · 1104.1542

Efficiency at maximum power of minimally nonlinear irreversible heat engines

Yuki Izumida·Koji Okuda
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Abstract

We propose the minimally nonlinear irreversible heat engine as a new general theoretical model to study the efficiency at the maximum power $η^*$ of heat engines operating between the hot heat reservoir at the temperature $T_h$ and the cold one at $T_c$ ($T_c \le T_h $). Our model is based on the extended Onsager relations with a new nonlinear term meaning the power dissipation. In this model, we show that $η^*$ is bounded from the upper side by a function of the Carnot efficiency $η_C\equiv 1-T_c/T_h$ as $η^*\le η_C/(2-η_C)$. We demonstrate the validity of our theory by showing that the low-dissipation Carnot engine can easily be described by our theory.

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Yuki Izumida, Koji Okuda. 2012-01-26. Efficiency at maximum power of minimally nonlinear irreversible heat engines. https://doi.org/10.1209/0295-5075%2F97%2F10004

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