An Evaluation of Encapsulated Oil Flooded Screw Compressor Systems

A study was carried out on oil injected compressors, to assess the value of compressor encapsulation in optimization of the compressor system and eliminating the need for an external oil separator. The analysis was performed using a proprietary software suite for estimating the performance and optimising the design of a screw compressor, when it is subjected to a higher environment temperature, due to its containment in the oil separator. Several features were further investigated by use of 3-D computational fluid dynamics. It was found that full encapsulation seriously worsens compressor performance. Accordingly it should be adopted only when justified by special circumstances. However, the semi-encapsulated compressors behave similarly to bare air ends. Thus, where they are cost effective, their adoption is to be encouraged.