抄録
This paper deals with a refrigeration system using CO_2 as the working fluid. The CO_2 refrigeration system has a cycle including trans-critical region at the high-pressure side due to its thermodynamic characteristics. This refrigeration system provides an advantage, when it is applied for both cooling and heating demand simultaneously in the temperature range from -30℃ to 80℃. Taking into account of operational data of a 40USRT CO_2 refrigeration system, which is installed at Waseda University, the effectiveness of the CO_2 refrigeration system applying to both cooling and heating demand at the same time in industries is discussed.
