吸附式制冷系统运行参数动态特性

Dynamic operating characteristics for adsorption refrigeration

针对燃料电池汽车余热驱动的吸附式制冷循环过程吸、脱附特性,采用动态的分析方法,对吸附式制冷系统的主要部件吸附床在不同阶段(等容加热、等压解吸、等容冷却、等压吸附)的工作过程建立动态方程,同时对制冷系统的蒸发器及冷凝器建立相应的动态模型。利用数值方法对数学模型进行求解,分析吸附速率、吸附床温度、冷凝温度、蒸发温度、制冷功率等参数随时间的动态变化规律。研究结果表明:吸附速率在吸附过程进行到5 min时达到峰值,吸附床温度达到350 K后其升温速率开始减慢,吸附床温度降到315 K后的降温速率开始减慢,冷凝温度在解吸阶段进行到8 min时存在1个峰值,蒸发温度的变化趋势与制冷功率的变化趋势相反。

Aiming at adsorption refrigeration cycle driven by waste heat of fuel cell electrical vehicle, applied method of dynamic analysis, dynamical equations of state for adsorbent bed were built up for different phases （heating for specific volume to fix, desorbing for pressure to fix, cooling for specific volume to fix and adsorbing for pressure to fix）, dynamic equations of state for evaporator and condenser were also built up, Mathematical models were solved by numerical method. The relationship between time and several parameters （adsorption rate, temperature of adsorbent bed, condensing temperature, evaporating temperature and cooling power） was discussed. The results show that adsorption rate at adsorption process reaches a peak value at 5 min, and heating rate starts reduce slowly when the temperature of adsorbent bed attains 350 K, and cooling rate starts to reduce slowly when the temperature of adsorbent bed attains 315 K. The condensing temperature in the desorption process reaches a peak value at 8 min, and the variation trend of the evaporating temperature and cooling power is reverse.