Comparative air conditioning performance using SiO2 and Al2O3 nanolubricants operating with Hydrofluoroolefin-1234yf refrigerant

Abstract

• Performance using SiO 2 and Al 2 O 3 Nanolubricants with Hydrofluoroolefin-1234yf. • Experiments are undertaken for different nanolubricants up to 0.05% concentration. • Cooling capacity of SiO 2 nanolubricant at 0.01% concentration improved up to 15.7% • Performance of Al 2 O 3 nanolubricant increased up to 9.8% at 0.05% concentration. • Type of nanolubricant contributed to variation parameter improvement of the system. Nowadays, the automotive air-conditioning system operating with Hydrofluoroolefin-1234yf or R1234yf refrigerant is used to reduce the global warming potential. This study aims to investigate the performance of SiO 2 and Al 2 O 3 nanolubricants with R1234yf refrigerant in the automotive air conditioning system. The polyalkylene glycol-based nanolubricant was prepared using a two-step preparation method, and the stability of the nanolubricant was assessed using visual sedimentation observation and zeta potential analysis. The experimental investigation on the performance of automotive air conditioning system with R1234yf was undertaken for the SiO 2 and Al 2 O 3 nanolubricants at different volume concentrations and various operating conditions. The system with SiO 2 nanolubricant at 0.01% volume concentration demonstrated the best cooling capacity performance with an average enhancement of 15.7%. On the other hand, the highest coefficient of performance increment and power consumption reduction were attained up to 9.8% and 27.1%, respectively for Al 2 O 3 nanolubricant at 0.05% volume concentration. The SiO 2 nanolubricant performed with better cooling capacity, higher power consumption and lower coefficient of performance than the polyalkylene glycol-based lubricant. In contrast, the Al 2 O 3 nanolubricant improved the coefficient of performance and reduced the power consumption. Since both nanolubricants provide their respective advantages, more research into integrating the two nanoparticles for refrigeration systems with R1234yf refrigerant is encouraged.