Influence of Oil Injection System on Efficiency of Speed-Controlled Screw Refrigeration Compressor

Abstract

The problems of enhancing the efficiency of screw refrigeration compressors with speed control of refrigeration output are studied. Based on a mathematical model developed, it is demonstrated that compressor efficiency depends a great deal on the operation of the oil injection system. When an oil injection system that ensures optimal compressor operation under fixed conditions is chosen, change in operation conditions does not cause significant loss of efficiency. At the same time, if the oil injection system is non-optimal, change in operation conditions does not enhance compressor efficiency. This means that the configuration of the oil injection system determines the level of compressor efficiency, which remains practically unchanged if the operation conditions are changed.