A Refrigeration System Using Air as Working Fluid
Author: Troy Davis
The manufacturer has developed a refrigeration system using air (R-729) as the working fluid. Air, a natural refrigerant, has no impact on the environment unlike conventional fluorocarbon refrigerants. The air refrigeration system produces the extremely low temperatures (-58°F/-50°C to -148°F/- 100°C) required in cold-storage warehouses and pharmaceutical and cryogenic applications. The system, which mainly comprises an integrated centrifugal compressor and expander, regenerative heat exchanger, and primary cooler, can save more than 30% of energy for the room cooling load when compared with conventional refrigeration systems that use fluorocarbon refrigerants, as shown in the following site example. This paper offers a brief history of industrial refrigeration and some basic refrigeration concepts before reporting on an air-based system and its applicable use.