Performance Prediction of Turbomachinery Cascades as Affected by Upstream Turbulence

(Received 21 September 1994, accepted 3 July 1995)

Abstract
The problem of predicting the quasi-2D performance of turbomachinery blade cascades is presently the object of a considerable amount of research, especially for off-design conditions where separation is occurring frequently. This interest is particularly vivid for the case of multi-blade row axial machines, where upstream wakes affect the blade operation, especially the transition and separation processes. This paper presents a fast modelling method, based on a strong coupling between a potential flow calculation and an integral approach for the boundary layer and separation regions, taking into account the main effects of the upstream wakes. Comparisons of global (loss and deviation) and local performance (local boundary layer parameters including the transition and separation regions) with and without upstream wakes effects are presented as well as with the scarce -and not always reliable- experimental data available.