title: Efficiency at maximum power of low-dissipation Carnot engines.
abstract: We study the efficiency at maximum power, η*, of engines performing finite-time Carnot cycles between a hot and a cold reservoir at temperatures Th and Tc, respectively. For engines reaching Carnot efficiency ηC=1-Tc/Th in the reversible limit (long cycle time, zero dissipation), we find in the limit of low dissipation that η* is bounded from above by ηC/(2-ηC) and from below by ηC/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 ηCA=1-√Tc/Th] is recovered.
authors.affiliation: Center for Nonlinear Phenomena and Complex Systems, Université Libre de Bruxelles, CP 231, Campus Plaine, B-1050 Brussels, Belgium.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Esposito
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Kawai
authors.forename: Katja
authors.initials: K
authors.lastname: Lindenberg
authors.forename: Christian
authors.initials: C
authors.lastname: Van den Broeck