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arXiv · 2002.09276

Work-extraction from fluid flow: the analogue of Carnot's efficiency

A. E. Allahverdyan
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Abstract

Aiming to explore physical limits of wind turbines, we develop a model for determining the work extractable from a compressible fluid flow. The model employs conservation of mass, energy and entropy and leads to a universal bound for the efficiency of the work extractable from kinetic energy. The bound is reached for a sufficiently slow, weakly-forced quasi-one-dimensional, dissipationless flow. In several respects the bound is similar to the Carnot limit for the efficiency of heat-engines. More generally, we show that the maximum work-extraction demands a contribution from the enthalpy, and is reached for sonic output velocities and strong forcing.

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A. E. Allahverdyan. 2020-02-18. Work-extraction from fluid flow: the analogue of Carnot's efficiency. https://doi.org/10.1103/physrevlett.125.064503

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