Variable capacity air cycle refrigeration system

Claim 1

An air cycle refrigeration system for supplying conditioned air to an enclosure said system comprising a compressor for increasing the pressure of supply airflow thereto, discharge airflow from said compressor being fed to a turbine through a primary nozzle thereof, said compressor discharge airflow driving said turbine and being expanded, and cooled thereby and discharged therefrom, means for delivering said turbine discharge air to said enclosure, said turbine and compressor being mechanically interconnected whereby said turbine provides a measure of input power for driving said compressor, said air cycle refrigeration system being characterized by means channeling an additional portion of said supply air to said turbine through a second nozzle thereof, thereby bypassing said compressor, and means for regulating the flow of said compressor bypass airflow to said turbine, in response to the amount of available supply airflow, said compressor bypass air, with said compressor discharge air, being expanded by said turbine for enhancing the flow capacity and output of said system without adversely affecting compressor efficiency.