Maximum Power Point Characteristics of Generalized Heat Engines with Finite Time and Finite Heat Capacities. (20th December 2012)

• Record Type: Journal Article
• Authors: Khanna, Abhishek; Johal, Ramandeep S.
• Other Names: Rosen M. A. Academic Editor.
• Is Part Of: Journal of thermodynamics. Volume 2012(2012)
• Publication Date: 2012-12-20
• Subjects: Thermodynamics -- Periodicals; Thermodynamics; Periodicals; Electronic journals; 536.7
• DOI: 10.1155/2012/246914
• Languages: English
• ISSNs: 1687-9244

Abstract

Abstract : We revisit the problem of optimal power extraction in four-step cycles (two adiabatic and two heat-transfer branches) when the finite-rate heat transfer obeys a linear law and the heat reservoirs have finite heat capacities. The heat-transfer branch follows a polytropic process in which the heat capacity of the working fluid stays constant. For the case of ideal gas as working fluid and a given switching time, it is shown that maximum work is obtained at Curzon-Ahlborn efficiency. Our expressions clearly show the dependence on the relative magnitudes of heat capacities of the fluid and the reservoirs. Many previous formulae, including infinite reservoirs, infinite-time cycles, and Carnot-like and non-Carnot-like cycles, are recovered as special cases of our model.