Efficiency at maximum power: An analytically solvable model for stochastic heat engines

TL;DR

This paper introduces an analytically solvable model for stochastic heat engines, deriving a universal efficiency at maximum power that differs from classical models, and illustrating it with a harmonic potential engine.

Contribution

The paper provides a new solvable model for stochastic heat engines and derives a universal efficiency at maximum power distinct from the Curzon-Ahlborn efficiency.

Findings

Universal efficiency at maximum power derived

Model illustrated with a harmonic potential engine

Efficiency at maximum power differs from classical models

Abstract

We study a class of cyclic Brownian heat engines in the framework of finite-time thermodynamics. For infinitely long cycle times, the engine works at the Carnot efficiency limit producing, however, zero power. For the efficiency at maximum power, we find a universal expression, different from the endoreversible Curzon-Ahlborn efficiency. Our results are illustrated with a simple one-dimensional engine working in and with a time-dependent harmonic potential.