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Register a new userEfficiency at maximum power of low dissipation Carnot engines
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Added by
Massimiliano Esposito
Publication date
2010
fields
Physics
and research's language is
English
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We study the efficiency at maximum power, $eta^*$, of engines performing finite-time Carnot cycles between a hot and a cold reservoir at temperatures $T_h$ and $T_c$, respectively. For engines reaching Carnot efficiency $eta_C=1-T_c/T_h$ in the reversible limit (long cycle time, zero dissipation), we find in the limit of low dissipation that $eta^*$ is bounded from above by $eta_C/(2-eta_C)$ and from below by $eta_C/2$. These bounds are reached when the ratio of the dissipation during the cold and hot isothermal phases tend respectively to zero or infinity. For symmetric dissipation (ratio one) the Curzon-Ahlborn efficiency $eta_{CA}=1-sqrt{T_c/T_h}$ is recovered.
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