EXPERIMENTAL STUDY OF A DOMESTIC REFRIGERATOR WITH POE-Al^sub 2^O^sub 3^ NANOLUBRICANT

This paper presents the performance of a minibar domestic refrigerator operating with and without nanoparticles of alumina oxide, Al^sub 2^O^sub 3^. The Al^sub 2^O^sub 3^ nanoparticles were mixed with polyolester (POE) lubricant to form nano-lubricant at 0.2% concentration by volume and were prepared via a two-step method. The evaluation was carried out by determining the general performance in terms of refrigeration capacity (Q^sub L^), compressor work, coefficient of performance (COP), and the power and energy consumption of the system working with both lubricants, POE-Al^sub 2^O^sub 3^ and POE. The refrigerator attained its optimum operating level at 42 psi for both. The performance of the refrigerator operating with POE-Al^sub 2^O^sub 3^ was improved compared with the system working with POE in terms of energy consumption and COP. The energy consumption of the refrigeration system with POE-Al^sub 2^O^sub 3^ at optimum refrigerant charge was the minimum and maximum COP of 321 Wh and 2.67. The highest percentage of energy consumption reduction was 2.1% at the optimum refrigerant charge.