AN EXPERIMENTAL STUDY ON THE IMPROVEMENT OF COEFFICIENT OF PERFORMANCE IN VAPOR COMPRESSION REFRIGERATION SYSTEM USING GRAPHENE LUBRICANT ADDITIVES

Nowadays, the impact of refrigeration on the environment is considered as an important problem in the research community. This phenomenon necessitates the need to improve the performance of refrigeration systems coupled with reduced environmental impacts. Previous researches revealed the use of additive combined lubricants that tend to improve the performance of Vapor Compression Refrigeration system (VCR). The current study experimentally investigated graphene nanolubricant additives in VCR. The graphene oil nanoparticles, of different volume concentrations, i.e.,, 0.025-0.15, were suspended in Polyester oil (POE). The researcher hypothesizes that the use of graphene nanoparticles with lubricants tend to improve the performance of VCR systems. Thermal conductivity, viscosity, and friction coefficient were calculated experimentally. The optimum volume concentration was identified during when the minimum friction coefficient was also obtained. The performance of the VCR system was also correlated with a base lubricant (POE oil). The results showed better performance in terms of heat removal rate, work input to the compressor and Coefficient of Performance (COP). The COP of the VCR system got enhanced upto similar to 29%. Therefore, it can be inferred that the graphene lubricant additives achieved higher performance than the base oil (POE) and it can be considered as a better replacement for base oil. Future researchers are recommended to use other such promising organic additives to improve the performance of VCR systems, and reduce the impact of refrigeration systems on the environment.