The characteristics of CO2 as refrigerants and analysis of CO2 trans-critical cycle

As the traditional refrigerant damage to the ozone layer, global warming and other environmental problems have become increasingly prominent, CO₂ has started to be emphasized again as an ideal refrigerant. The characteristics of CO₂ as refrigerants are introduced. The CO₂ trans-critical cycle is analyzed and summarized in detail. The methods of improving cycle performance are proposed, which include decreasing gas cooler outlet temperature and increasing evaporation temperature.