A novel approach to high resolution compressible cascade flow analysis using the Navier-Stokes equations

Abstract

This paper deals with the development of a technique aimed at improving the accuracy of 2-D flow solutions of turbomachinery problems. The basic concept is to take a quasi-3D Navier-Stokes or Euler solver on a coarse mesh (the "outer code") and couple it to a 2-D space marching parabolised Navier-Stokes solver on a finer sub-mesh (the "inner code"). The "inner-code" includes the FLARE approximation to permit reverse flow. The inner and outer codes are coupled by adopting an approach analogous to classical multigrid methods. The combination forms a cheap and fast solver to provide fine resolution solutions using only mini-computer resources. Predictions of the flow through a compressor and a turbine cascade are described and show good agreement with the experimental results.