Three-Dimensional Flow Calculations of the Stator in a Highly Loaded Transonic Fan

Abstract

A 3D viscous solver has been used to model the flow in the stator of a highly loaded single-stage transonic fan. The fan has a very high level of aerodynamic loading at the hub, which results in a severe hub endwall stall. Prediction of the flow at the 100% speed, peak efficiency condition has been carried out and comparisons are made with experiment, including stator exit traverses and fixed blade surface pressure tappings and flow visualisation. Comparisons are also made with an analysis of the rotor and stator rows using the DRA S1-S2 method. The 3D predictions show good qualitative agreement with measurements in all regions of the flow field. Quantitatively the flow away from the hub region agreed the best. The general trends of the severe hub endwall stail were predicted, although the shape and size did not match experiment exactly. The S1-S2 system was unable to predict the hub endwall stall, since it arises from fully 3D flow effects.