Development of a viscous cascade code based on scalar implicit factorization

Abstract

A viscous cascade code has been developed, first for two-dimensional configurations and then extended to three-dimensional linear cascades with flat, parallel endwalls. It employs scalar implicit approximate factorization, a finite-volume formulation, second-order upwind differencing, and a two-equation q-u turbulence model based on integration to the wall. A special form of the thin-layer approximation for the compressible NavierStokes equations is used that gives accurate skin-friction predictions on highly skewed meshes, now based on sheared H-grids. The two-dimensional code has been validated by considering test cases for NASA energy efficient engine (E) blade and vane cascade geometries. The turbulence model displays proper boundary-layer transition behavior. The three-dimensional E vane cascade also has been considered with straight endwalls. Agreement with experiment is quite good.