Interacting flow effects in the stages of a low-speed multistage axial compressor using shrouded and cantilevered stators

This paper describes the analysis of the flow field in a 4-stages low speed axial compressor at design point investigated both numerically and experimentally, with particular emphasis on the impact of stator hub flow leakage in a section of the machine featuring a change of stator configuration. The goal of the work is to give further insight into the effect of the stator hub configuration on the aerodynamic performance in terms of loss and efficiency of downstream blade rows as well as the resulting stage matching effects. Two stator hub configurations, shrouded and cantilevered, which are commonly employed in industry, are investigated and discussed with respect to local flow phenomena and stagewise aerodynamic effects. The investigation is focused on the aerodynamic behaviour and stage interaction, which the stator hub configuration of a given stage induces in a downstream stage with respect to its performance and flow field.