Performance optimization of irreversible ferromagnetic Stirling heat pumps


Department of Physics and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen 361005, P. R. of China


An irreversible Stirling heat pump cycle using ferromagnetic materials as a cyclic working substance is established. The influences of finite-rate heat transfer, heat leak, regeneration time, regenerative loss
and the internal irreversibility on the cyclic performance of magnetic heat pumps are taken into account. On the basis of the thermodynamic properties of ferromagnetic materials, the performance characteristic
of the ferromagnetic Stirling heat pump cycle is investigated. Also, by applying the optimization technology, the relation between the optimal heating load and the coefficient of performance (COP) is derived.
Furthermore, the maximum heating load and the corresponding COP as well as the maximum COP and the corresponding heating load are determined and discussed in detail. The results obtained in the present
paper may provide some new information for the optimal design and the development of real magnetic heat pumps.