CFD Analysis of Discharge Gas flow in Rotary Compressor for OCR reduction

This paper presents the use of CFD as a design tool in the development of rotary compressor for the purpose of reduction in Oil Circulation Rate (OCR). In the present work, CFD analysis is done using a commercial CFD package to simulate the discharge gas flow within the rotary compressor. Discharge gas flow path in the compressor is redefined by providing features that support OCR reduction. One such feature is providing a few holes in the stator lamination. The no of holes, size and locations are optimized for similar motor performance as that of original design with the help of electromagnetic Simulation packages. The effect of holein-stator design on gas flow is evaluated using CFD and is further optimized for improved gas flow in terms of flow velocities and pressure drop at various sections inside the compressor to achieve reduction in OCR. Prototype compressors were built and tested, the practical performance in terms of OCR is in line with the CFD study.