耦合双循环冰箱运行参数与耗电量实验研究

Experimental Research on Operating Parameters and Power-consumption of Coupled Dual-loop Refrigerator/Freezer

本文研究了耦合双回路冰箱样机在不同工作状态下的运行参数,同时在标准工况下测量了系统耗电量,并与现有产品进行对比。结果表明:系统在耦合运行后,冷藏循环负荷增加导致两台样机冷藏循环的冷凝压力比耦合前分别上升23 kPa和40 kPa,蒸发压力比耦合前分别上升18 kPa和32 kPa,同时还造成冷凝器和蒸发器出口温度的上升;耦合运行对于冷冻循环的影响主要表现在冷凝压力及冷凝器出口过冷度的下降。其中样机Ⅰ冷冻循环的冷凝压力下降27 kPa,过冷度下降1.4℃。样机Ⅱ由于独立运行时冷凝器出口过冷度较小,耦合运行后冷凝压力下降超过160 kPa,导致冷凝压力低于环境温度对应的饱和压力,冷凝器中没有潜热交换。标准条件下的耗电量实验表明,耦合双循环冰箱系统比改造前的传统冰箱系统节能8%。

Coupled dual-loop system has been shown to possess energy-saving potential in the domestic refrigerator domain.However,whether the system could operate steadily under designed conditions and how efficiently the system performs under national standard testing condition have not been taken into account.This study investigated the operating parameters of two refrigerator prototypes,wherein the power consumption of one prototype was tested and compared to an existing product.Results revealed that when the system was operated with coupled clual-loop,the condensing pressure of two refrigerators would increase by 23 and 40 kPa,respectively,in comparison with the case prior to the coupling.Moreover,increments of 18 and 32 kPa for the evaporating pressure of the separate refrigerators were obtained,which were accompanied by the corresponding increases in the outlet temperatures of condenser and evaporator.These increments were attributed to the cooling load of the refrigerators.From the viewpoint of the freezer,the coupling operation would decrease the condensing pressure and degree of subcooling at the condenser outlet.The condensing pressure and degree of subcooling of the freezer with prototype I decreased by 27 kPa and 1.4℃after coupling,respectively.Furthermore,as the initial degree of subcooling of the freezer with prototype II was insufficiently large,the condensing pressure of the freezer decreased by approximately 160 kPa after the coupling operation,which was even lower than the saturated pressure of the ambient temperature which finally resulted in a no-latent heat exchange in the condenser.Under standard conditions,the energy-consumption tests showed that the efficiency of the new refrigerator is 8%higher than that before the alternation.