An experimental comparison between a microchannel cooler and conventional coolers of a CO2 air conditioning cycle

This paper presented an experimental comparison between a microchannel cooler and two conventional coolers of a CO₂ air conditioning cycle. The conventional coolers and the microchannel cooler were designed to have the same heating capacity; however, the volume of the microchannel cooler is less than conventional coolers. The results indicated that the heat transfer efficiency of the microchannel cooler is higher than those of conventional cooler. However, when cooler pressure was over 100 bar, the microchannel cooler was torn. So, the microchannel cooler should be used at the cooler pressure under 75 bar. In addition, the cycle performed at the evaporative temperature of 9°C, calculating the COP of 6.6 (negligible heat transfer rate of subcooling process). The COP of present study is higher than those obtained from other literature reviews.