ABSTRACT
Carbon dioxide, as a kind of natural refrigerant, is making great contribution to reducing the ozone depletion, reducing the Green House Effect and promoting the sustainable development of environment. This refrigerant is widely used in automobile air conditioning, water heater, and so on. System adopt CO2 are usually transcritical cycle, and gas cooler is a key component in the system. For the CO2 is in supercritical gas status, the heat transfer characteristic is not very clearly.
