The Performance Influences of a Centrifugal Compressor Due to Volute Local Deformation

Abstract

Centrifugal compressors have broad applications in gas compression processes, especially in automobile turbocharger. During the turbocharger installation, there are many installation limitations in the compressor stage. Due to the restriction in the size of the engine bay, it always has limitations of installation for turbochargers. The compressor package always requests to modify the compressor geometry to fit specific constraints. The volute is the largest geometry of the turbocharger package in most of the case. Very often modifications of the volute were performed to meet the space constraints. In this study, the authors investigated the compressor performance for an initially designed volute and a modified volute. The study followed by an on engine performance comparisons, compressor performance gas stand tests and computational fluid fynamics (CFD) analysis. The studies provided the performance impacts of the local volute deformation due to installation constraints, i.e., a kink in a volute. The studies showed the local volute kink has small implications on compressor performance when the maximum kink depth is less than 10% of the local volute hydraulic diameter. The numerical analysis is in favorable agreements with experiments. The results of this study can be used as a basic guideline for local deformation performance impacts for the future turbocharger compressor volute modifications.