Carnot cycle at finite power: attainability of maximal efficiency.

نویسندگان

  • Armen E Allahverdyan
  • Karen V Hovhannisyan
  • Alexey V Melkikh
  • Sasun G Gevorkian
چکیده

We want to understand whether and to what extent the maximal (Carnot) efficiency for heat engines can be reached at a finite power. To this end we generalize the Carnot cycle so that it is not restricted to slow processes. We show that for realistic (i.e., not purposefully designed) engine-bath interactions, the work-optimal engine performing the generalized cycle close to the maximal efficiency has a long cycle time and hence vanishing power. This aspect is shown to relate to the theory of computational complexity. A physical manifestation of the same effect is Levinthal's paradox in the protein folding problem. The resolution of this paradox for realistic proteins allows to construct engines that can extract at a finite power 40% of the maximally possible work reaching 90% of the maximal efficiency. For purposefully designed engine-bath interactions, the Carnot efficiency is achievable at a large power.

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عنوان ژورنال:
  • Physical review letters

دوره 111 5  شماره 

صفحات  -

تاریخ انتشار 2013