Modeling and optimization of an endoreversible non-isothermal chemical pump cycle via Onsager equations

Abstract

Assuming that the heat-and-mass-transfer process obeys the Onsager equations in linear irreversible thermodynamics, a model for an endoreversible non-isothermal-chemical-pump cycle is built, and its performance is optimized. The analytical results of rate of energy-pumping and vector coefficient of performances (See Eq. (20) in this paper for its definition) are obtained. Effects of cycle design parameters on the cycle optimal performances are analyzed. The findings show that: With the increase of energy flux, the rate of energy-pumping increases, and vector coefficient of performances decrease. With the increase of mass-transfer flux, the rate of energy-pumping is unchanged. The surfaces of rate of energy-pumping versus vector coefficient of performances are monotonically decreasing ones, and with increase of cross-phenomenological coefficient of heat-and-mass-transfer, the vector coefficient of performances increase. Research results involve two special cases: the optimal performance for an endoreversible Carnot heat-pump cycle with linear phenomenological heat-transfer law and the optimal performance for an endoreversible isothermal chemical pump with linear mass-transfer law.