Performance of Al2O3/TiO2 nano composite particles in domestic refrigerator

This article presents an experimental investigation of domestic refrigerator using R134a as working fluid with different concentration of Al2O3, TiO2 nano particles and nano composite particles dispersed in polyolester (POE) oil lubricant. All the nano particles were added to the POE oil with 0.1gL−1 volume concentration. The experiments are conducted for different compositions such as R134a with POE oil, R134a with nano lubricant (Al2O3/POE oil and TiO2/POE oil) and R134a with nano composite lubricant (75% Al2O3/25% TiO2/POE oil, 50% Al2O3/50% TiO2/POE oil and 25% Al2O3/75% TiO2/POE oil). Both second law analysis and performance analysis was conducted. Analysis was based on temperature and pressure readings measured from various sensors and gauges which is attched to the system. The test conducted at −18 °C temperature in evaporator with reference to 27 °C environment state. Findings show that best performance is given by R134a with nano composite lubricant 50% Al2O3/50% TiO2/POE oil which results in lowest power consumption of 92.2 W, highest actual coefficient of performance of 2.33, lowest compressor work of 61.24 kJ/kg, lowest total irreversibility of the system of 36.19 kJ/kg and highest second law efficiency of the system of 40.9%. Thus, using this nano composite fluid mixture as lubricant in domestic refrigerator is suggested