A Review of Non-Steady Flow Models for Compressor Stability

Abstract

This paper presents a review of the different approaches to modelling the non-steady fluid dynamics associated with two-dimensional compressor flowfields. These models are used to predict the time development of flowfield disturbances and have been found useful both in the study of rotating stall and the development of active control. The opportunity to digest the earlier investigations has now made it possible to express the modelling ideas using only a very simple mathematical treatment. Here, the emphasis is on the underlying physical processes that the models simulate and how the assumptions within the models affect predictions. The purpose of this work is to produce, in a single document, a description of compressor modelling techniques, so that prospective users can assess which model is the most suitable for their application.