Research on defrosting of refrigerator using phase change material heat exchanger

During the operation of an air-cooled refrigerator, a frost layer is formed on the surface of the evaporator, which diminishes the cooling capacity and coefficient of performance. This paper reports on the design of a new system using heat storage phase-change materials to alleviate the above problems. The new system not only uses the waste heat of the compressor housing to defrost, but also collects the heat of the condenser to provide domestic hot water, without the need for additional equipment to provide heat. Compared with electric defrosting, the average defrosting time and average total energy consumption of the new defrosting method are reduced by 37% and 74.3%, respectively, and the temperature fluctuation in the freezer is also weakened. In addition, about 4.5 L of water can also be heated to the temperature of domestic hot water in a single cycle, saving energy costs. Experimental results well prove the superiority of the new system in existing refrigerator products.