▎ 摘　　要

Graphene nanosheet have an ultra-thin sheet structure that can easily fill the contact friction surfaces and reduce friction losses. Its thermal conductivity reaches 5,300 W/mK. Therefore, a nanofluid prepared by adding graphene nanosheets to base liquid will have lower coefficient of friction and higher thermal conductivity. In this study, 1:1 mass ratio of graphene nanosheets additive to Span85 dispersant was added to SUNISO 3GS refrigerant oil, using ultrasonic oscillation dispersing and chemical methods to prepare 10 mg/L, 20 mg/L and 30 mg/L graphene nanosheets refrigerant oil. The cooling rate, freezing capacity, and energy consumption of the refrigerator using different concentrations of graphene nanosheets refrigeration oil were compared. The performance of the compressor and the refrigerator were analyzed. The results showed that during the stable refrigerator operation, adding graphene nanosheets to lubricants for the refrigerator had lower suction temperature, discharge temperature, condenser temperature, suction pressure and discharge pressure than pure oil. Both the fresh food compartment and freezer's cooling rates were increased. The increase of the concentration leaded to better freezing capacity of the freezer. The 30 mg/L graphene nanosheets refrigerant oil increased the freezing capacity of the refrigeration system by 11.1%. The on-time ratio, operating current of the compressor and energy consumption were also reduced. Compared with pure oil, the energy consumption in 24 h of the domestic refrigerator using 10 mg/L, 20 mg/L and 30 mg/L graphene nanosheets refrigerant oil dropped by 15.4%, 19.2% and 20.3%. (C) 2019 Elsevier Ltd and IIR. All rights reserved.