New refrigeration system using CO vapor-solid as refrigerant

Abstract

A refrigerant must be in the vapor-liquid phase in a vapor-compression refrigeration system, therefore, CO₂ cannot be used as a refrigerant for temperatures lower than -56°C because solid CO₂ will form under the triple point temperature of -56°C. A refrigeration system with CO₂ vapor-solid particles as refrigerant is put forward, by which a temperature lower than the triple point is achieved. An adjustable nozzle, a sublimator, a high-pressure regulating valve and a low-pressure regulating valve are used to replace the conventional evaporator. Theoretical cycle analysis of the refrigeration system shows that its COP can be 50% higher than that of the conventional one.

Keywords

carbon dioxide / solid particle / refrigeration system