Thermal Performance Curve Analysis for Enhancement of an Air Conditioner in Thailand

Abstract

This study presents a method for analysing air conditioner efficiency by using a thermal performance curve. Enhancement techniques consisting of the use of a phase change material (PCM), a vapor compression heat pump (VCHP), ultrasound, drop-in refrigerant, a commercial R-32 air conditioner using ultrasound and a double-storage tank are reported under the weather conditions in Thailand. For the PCM, Rubitherm20 (RT-20) in the forms of a paraffin ball and a plastic pack was selected to cool the return air of the evaporator, which directly caused decreases in power consumption of 7.85% and 5.78%, respectively. The R-123 VCHP was integrated with the air conditioner at the condenser to receive and boost rejected heat to the hot water temperature of 60–70∘C. Ultrasonic wave generators at 42[Formula: see text]kHz frequency were installed at the evaporator to improve heat transfer characteristics and reduce the electrical power usage of the air conditioner by 8%. The R-32 drop-in refrigerant technique was tested in an R-410a air conditioner model. The R-32 unit showed the advantages of a smaller environmental impact and a higher cooling energy efficiency ratio (EER) compared with that of the R-410a unit. Moreover, the commercial R-32 air conditioner and a 40 kHz ultrasonic generator were integrated. The combined unit revealed a higher EER of 7.69% compared with that of the conventional commercial R-32 unit. For a double-storage tank, it was shown that the maximum hot water temperature in the storage tank was approximately 49∘C. The highest effective method to enhance the cooling capacity of air-conditioner is the technique of R-32 air conditioner and ultrasonic wave for increasing the cooling efficiency of 8.54%.