Energy and exergy analyses of an active magnetic refrigerator

Abstract

In this paper, a thermodynamic model for predicting the performance of active magnetic refrigerator (AMR) is developed using energy and exergy analyses. Through this model, the cooling power, total power consumption, as well as the coefficient of performance (COP), exergy efficiency and exergy destruction rates of an AMR are determined. The effects of increasing mass flow rate on the COP, exergy efficiency and exergy destruction rates of the system are investigated. The results are presented to show that when mass flow rate increases, the COP and exergy efficiency curves reach their maximum values and then slightly decreases with increasing mass flow rate. The rate of exergy destruction increases with increasing mass flow rate due to the pump power requirements. The numerical results show that in order to reach optimal performance, mass flow rate must be adjusted carefully regarding to different operating conditions.