Low-inertia centrifugal compressor wheels: Aerodynamic and mechanical design

Abstract

A new centrifugal compressor impeller design approach is presented, focusing on electrically driven compressors for gasoline engine and fuel cell applications. The performance and mechanical integrity are evaluated based on numerical simulations. Additionally, the numerical model is applied to several variations of the diffuser and volute geometries, in order to evaluate stage characteristics for diffuser area ratios of 110% and 150%, volute area ratios from 60% to 90%, and diffuser pinch ratios from 60% to 80%. The preliminary performance results show the capability to achieve a flow range comparable to a larger state-of-the-art impeller, with minor penalties regarding stage efficiency and near surge operating stability.