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arXiv · 1307.0175

Coefficient of performance for a low-dissipation Carnot-like refrigerator with nonadiabatic dissipation

Abstract

We study the coefficient of performance (COP) and its bounds of the Canot-like refrigerator working between two heat reservoirs at constant temperatures $T_h$ and $T_c$, under two optimization criteria $χ$ and $Ω$. In view of the fact that an "adiabatic" process takes finite time and is nonisentropic, the nonadiabatic dissipation and the finite time required for the "adiabatic" processes are taken into account. For given optimization criteria, we find that the lower and upper bounds of the COP are the same as the corresponding ones obtained from the previous idealized models where any adiabatic process undergoes instantaneously with constant entropy. When the dissipations of two "isothermal" and two "adiabatic" processes are symmetric, respectively, our theoretical predictions match the observed COP's of real refrigerators more closely than the ones derived in the previous models, providing a strong argument in favor of our approach.

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BibTeXRIS

Yong Hu, Feifei Wu, Yongli Ma, Jizhou He, Jianhui Wang, A. Calvo Hernandez, J. M. M. Roco. 2013-06-30. Coefficient of performance for a low-dissipation Carnot-like refrigerator with nonadiabatic dissipation. https://doi.org/10.1103/physreve.88.062115

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