喷射式制冷系统的仿真计算和实验研究

Simulation and Experimental Study of the Ejector Refrigeration System

基于CFD模型计算和喷射式系统实验设备,对喷射器结构参数、工况条件对喷射系数ER和机械COP的影响进行了分析。实验结果显示:喷射系数ER和机械COP均随喷嘴喉部直径Dn、引射器喉部直径De的增加呈现先升高后减小的变化趋势,当Dn=5 mm、De=17 mm时,两者达到最大值;喷射系数ER和机械COP同样均随发生温度的升高呈现先急剧升高后缓慢减小的变化趋势,当Tgen=72℃时,两者取最大值;Tcon<40℃时,喷射系数ER受冷凝温度的影响较小,而当Tcon>40℃时,喷射系数ER急剧下降;机械COP随冷凝温度的升高呈现先升高后减小的变化趋势,当Tcon=40℃时得最大值。

Based on CFD model calculation and experimental equipment of ejector refrigeration system,influence of injector structural parameters and working conditions on injection coefficient ER and COP are analyzed.Experimental results show that injection coefficient ER and COP all increase firstly and then decrease with the increase of nozzle throat diameter D_n and ejector throat diameter D_e,they reach the maximum value when D_n is equal to 5 mm and D_e is equal to 17 mm;injection coefficient ER and COP also show a sharp trend increase and then decrease slowly with the increase of generation temperature,they reach the maximum value when generation temperature is equal to 72℃;condensation temperature has a little influence on injection coefficient ER when condensation temperature is less than 40℃while injection coefficient ER drops sharply when condensation temperature is more than 40℃;injection coefficient ER and COP increases firstly and then decreases with the increase of condensation temperature,and the maximum value is reached when condensation temperature is equal to 40℃.