Review of dedicated mechanical subcooling methods for transcritical CO2 refrigeration and heat pump cycles

The transcritical CO₂ cycle mode has become one of the most popular research topics in the refrigeration field due to its advantages such as environmental friendliness, high-temperature heating performance, and adaptability to low environmental temperatures. This article discusses the thermodynamic principles and research progress of DMS technology for transcritical CO₂ refrigeration heat pumps, providing reference for academic research and engineering applications. The research results indicate that the dedicated mechanical subcooling technology (DMS) for the transcritical CO₂ cycle has broad development prospects in the field of refrigeration and heating. DMS technology can increase the COP of the transcritical CO₂ cycle by more than 20%, and in some scenarios, it can already achieve the effect of replacing artificial synthetic refrigerants.