Modifications of a Two Stage Centrifugal Compressor for the Volute and Vaneless Diffuser Study

Abstract

The objective of this work was to establish an advanced testing facility for studying the flow structure and loss mechanism in a single stage centrifugal compressor. A Trane’s CVHF 1280, two stage centrifugal compressor was modified to a single stage for laboratory environment. This modification included new fluid medium, driving motor, inlet and outlet designs. In this study, experiments were performed in order to evaluate the performance of the vaneless diffuser and volute. However, the modifications enable the flow structure investigation in all components of the compressor as well. In addition the testing facility would accommodate installation of the rest of the unit for investigation of the flow in the vaned diffuser and return channel of the two-stage compressor in the laboratory environment. Experiments were performed in three speeds and eight mass flow rates per speed. Static and total pressures were measured at the inlet and outlet of the stage. Static pressure distributions were mapped on the vaneless diffuser and volute casings. These data evaluates the characteristics of these components after the modifications.