【摘要】 结合分子场理论和磁系统热力学知识,分析了回热式室温磁Ericsson制冷循环中热量和磁熵的关系,重点研究了热源温度对铁磁质磁Ericsson制冷循环性能的影响。利用典型室温磁制冷材料Gd进行了数值计算,得到以下结论:居里点附近是循环中的重要转折点,TL低于居里点会出现△Q<0的情况,一旦高于居里点则只有△Q>0的情况;TL越高对应的高温热源最大值THmax越高;相同高、低温热源条件下,磁场越大COP变化率越小。更多还原

【Abstract】 On the basis of the molecular- field theory and thermodynamics of magnetic system, the relation between heat and magnetic entropy change of the regenerative room - temperature magnetic Ericsson refrigeration cycle was analyzed in our study. Moreover, the influence of the temperature of heat reservoir on the performance of ferromagnetic magnetic Ericsson refrigeration cycle was investigated. The numerical simulation for the magnetic refrigeration cycle with typical ferromagnetic material Gadolinium was conducted. The results show that there will be an important turn of the cycle performance near the Curie temperature. Whenever temperature is higher than Curie temperature, only the condition of occurs, otherwise, both conditions appear. In addition, the maximum of high- temperature heat reservoir increases with the increase of low- temperature heat reservoir. And for the same heat reservoir, the increase rate ofde-creases while magnetic field strength increases.更多还原