Studied thermal properties and cycle charactes of the CO_2 natural refrigerant in order to make CO_2 transcritical cycle more perfectly and to substitute for CFCs and HCFCs refrigerants.

• 对自然工质CO_2的热力性质、循环特性进行分析研究,以求进一步完善R744循环,以替代CFCs和HCFCs制冷工质。