旋转式磁制冷机主动式回热器周期性温度场试验

Experimental Investigation on Periodical Temperature Field in Active Magnetic Regenerator of Rotary Magnetic Refrigerator

采用测量主动式回热器温度场的方法,探讨了周期性瞬态内热源作用下的多孔介质与单相流体的换热规律.实验结果表明:旋转式磁制冷机主动式回热器内温度场波动频率与磁制冷机转动频率相等.当制冷机转速增大时,温度场的波动频率相应增加,工质轮整体的温度降低,加磁区与去磁区温度场的波动频率相等,两磁区的波动相位移近似为180,°去磁区温度场振幅是加磁区温度场波动振幅的2倍左右.但是当流量增大到2.639×10-4m3/s时,温度趋于饱和,设计时应选择低于临界换热介质的流量.

The heat transfer rules between the porous medium and single-phase fluid under the periodical instantaneous heat source in the active magnetic regenerator （AMR） of a rotary magnetic refrigerator were discussed based on temperature field measurement. The experimental results showed that the temperature vibration frequency in the AMR was equal to the rotational frequency of the AMR. With the increasing of the rotational frequency of the AMR, the temperature vibration frequency increased accordingly, but the temperature values decreased. On the other hand, the temperature vibration frequencies in demagnetizing area and magnetizing area were the same, the vibration phase shift between the two areas was about 180 degrees, and the vibration amplitude of the former area was nearly twice as lange as that of the latter one. Generally, increasing the rotational frequency of the AMR has a positive effect on the refrigeration capacity, but the temperature reached its climax as the fluid flow increased to 2. 639×10^-4m^3/s, so the heat transfer fluid flow should designed to be less than the critical value.