二级不可逆磁Brayton制冷循环性能分析及参数优化

PERFORMANCE ANALYSIS AND PARAMETRIC OPTIMIZATION OF A TWO-STAGE IRREVERSIBLE MAGNETIC BRAYTON REFRIGERATION CYCLE

建立受有限速率热传导和绝热过程不可逆性影响的二级磁Brayton制冷循环模型,导出循环的性能系数和制冷率表达式,分析等磁场过程的磁场比、绝热不可逆因子、等磁中冷过程等对二级不可逆磁Brayton制冷循环最大制冷率及相关参数的影响,所得结论能为提高磁制冷机的循环性能提供参数设计参考。

A two-stage magnetic Brayton refrigeration cycle model affected by finite-rate heat transfer and irreversibility in the adiabatic processes is established. The analytical expressions of the coefficient of performance and cooling rate for the refrigeration cycle are derived. The influences of the ratio of the magnetic field intensities in the iso-magnetic field processes, irreversible adiabatic factors, and iso-magnetic field inter-cooling process on the maximum cooling rate and the corresponding performance parameters of the cycle are analyzed and discussed. The results obtained here may provide some references to enhancement of the cycle performance and optimal design of the operating parameters of magnetic refrigerators.