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arXiv · 2605.02732

Geometric Formulation of Power-Efficiency Bounds in Carnot-like Engines

R. X. Zhai
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Abstract

We formulate the power-efficiency constraint of Carnot-like heat engines as a geometric optimization problem in the plane of normalized branch dissipations. In this plane, efficiency contours are straight lines, so maximizing the efficiency at fixed power reduces to bounding the slope of an admissible line. For branch dissipations that scale inversely with a power of the process time, the fixed-power constraint defines a two-dimensional attainable region, and the resulting slope-bound problem reduces to a linear-programming problem. This geometric framework yields the exact power-efficiency constraint for Carnot-like heat engines with power-law dissipation.

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R. X. Zhai. 2026-05-04. Geometric Formulation of Power-Efficiency Bounds in Carnot-like Engines. https://arxiv.org/abs/2605.02732

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