3种节流机构在陈列柜制冷系统运行中的性能对比实验

Contrast experimental study on the performance of three throttle mechanisms employed in the refrigeration system of display case

在研制脉冲膨胀阀的基础上,对3种节流机构在低温陈列柜制冷系统运行中进行了性能实验对比。结果表明使用脉冲膨胀阀的制冷系统运行状态有别于热力膨胀阀和传统的电子膨胀阀,其蒸发器制冷剂蒸发温度在开机较短时间内达到稳定状态,并继续维持这一稳定温度,且系统蒸发器内制冷剂的过热度较小,同时使用脉冲膨胀阀的陈列柜柜温降温速度较快,柜温稳定性较好。同时脉冲膨胀阀可任意调节系统的供液系数来改变循环的制冷剂供液量及系统的蒸发压力和蒸发温度,使系统更好的适应环境变化要求,提高制冷系统的运行经济性。

The contrast experimental study on performance of three throttle mechanisms employed in the refrigeration system of low-temperature display case individually was carried out based on the new impulse expansion valve developed by ourselves. The results show that the variation of temperature in the evaporator adopting impulse expansion valve is different from that using thermostatic expansion valve or electronic expansion valve. The inlet and outlet temperature of the evaporator can reach the steady evaporating temperature in a short time and the superheated temperature can be maintained in a small range. The temperature of the display case decreases quickly initially and then slows down gradually, whereas the on-off interval of compressor is longer and the stability of the case temperature is better than those which employ the other two expansion valves. The results also show that the impulse electron signal can be adjusted at will to alter the refrigeration system＇ s operating condition. More effective impulse expansion valve system can be further developed to reduce energy consumption and improve the efficiency of the refrigeration system.