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

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 نشر من قبل Tim Schmiedl
 تاريخ النشر 2007
  مجال البحث فيزياء
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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.



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