Evaluation and Analysis of an Agro-Based Nano Refrigerant to Improve the Performance of a Domestic Refrigeration System

The use of nanoparticles along with the conventional refrigerant in a vapor compression cycle is relatively a new idea, where nano-refrigerants are found to have improved thermophysical properties over the conventional refrigerants. Nano-refrigerant is the combination of nanoparticles with the refrigerant to improve the performance of the refrigeration process. In this study, a developed nanofluid from agricultural source (rice husk) was applied in a domestic refrigerator and its performance investigated. The pre-developed nanofluid which was prepared using the synthesis, centrifugation and calcinations processes was administered in the compressor of the refrigerator at concentrations of 0.2wt%, 0.3wt%, 0.5wt% and 0.6wt% to form a mix with refrigerant R600a used in the compressor (as control) and allowed to run for 4 hours. Performance evaluation was measured using parameters such as pull down time, discharge temperature and coefficient of performance (COP). Results show an increase in the COP by 31, 23 and 35% compared to the control sample for the 0.2wt%, 0.3wt% and 0.5wt% concentrations respectively. The sample 0.6wt% and 0.5wt% showed the best pull down time with temperatures of -6.1 and -3.1℃ at 240 minutes respectively and a reduced discharge temperature of 7-16% by the 0.2wt%, 0.3wt% and 0.5wt% concentrations in respect to the control sample. Hence, the use of rice husk based nanofliud resulted in an enhanced performance for the domestic refrigerator.