SELF-COOLED AIR REFRIGERATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To solve the problem of a prior art air refrigeration system employing air as refrigerant that low temperature air on the order of -100 deg.C can be produced but when air of lower temperature is produced, the pressure ratio exceeds 10 to cause deterioration in the performance of a compressor and a turbine constituting an expansion machine and power is increased because the pressure ratio must be increased furthermore, and a problem that a refrigeration machine employing a CFC based or ammonia refrigerant is employed in the cooling method and since these refrigerants are atmosphere pollutants, they have a significant adverse effect on the human body upon leakage. SOLUTION: The air refrigeration system is provided with a bypass pipe for feeding low temperature air from a turbine outlet pipe to a heat exchanger disposed at the turbine inlet in order to cool the air at the turbine inlet. The turbine outlet pipe and the bypass pipe are provided with pressure regulation valves in order to operate the air refrigeration system while combining the pressure ratio and the volume of low temperature air for cooling the air at the turbine inlet optimally depending on a required temperature.