CONTRIBUTIONS TO THE UNDERSTANDING OF FLOW PULSATION LEVELS AND PERFORMANCE OF A TWIN SCREW COMPRESSOR EQUIPPED WITH A SLIDE VALVE AND A STOPPER FOR CAPACITY CONTROL

摘要

This paper discusses from a theoretical viewpoint the flow pulsation of a twin screw compressor and how it is related to performance. The compressor is equipped with a stopper in addition to a slide valve for controlling its capacity and the compression ratio. The volume ratio(V_i), the flow capacity, the power consumption rate and the flow pulsation level are determined based on a geometrical characterization in terms of volume versus shaft angle as input and a thermodynamic analysis of a screw compressor for no leakage. Typical results are shown in a plot form for various operating conditions defined by the stopper stroke, the bypass port opening area, the driving rotor speed and the compressor discharge pressure.