Performance Evaluation of an Internal Flow Navier-Stokes Solver for Compressible Viscous Flow Simulations

A three-dimensional compressible full Navier-Stokes solver is developed for the analysis of the flow field inside turbomachinary cascades. The solver uses an explicit second order accurate (cell-vertex) finite volume Lax-Wendroff scheme over hexahedral cells. The viscous and heat conduction terms are discretized in conservative form at the cell center. Second and fourth order numerical smoothing terms are added with local scaling factors. Eddy viscosity is calculated by the Baldwin-Lomax model and is adapted to the pointered cell based algorithm. Turbulent viscosity is blended by inverse distance square weighting functions near corners. Characteristic boundary conditions are used. A computational analysis has been carried out to present the capability of the solver in capturing secondary velocity patterns, flow angles and total pressure loss distributions inside a linear high turning turbine cascade. A controlled diffusion compressor cascade at high incidence has been analyzed. Main features of the flow field in this compressor cascade were resolved (secondary and end wall flows and leading edge laminar separation bubble) as in the experimental data. The main aim of the work is to demonstrate the performance of the code in capturing the details of the complicated flow fields using grids that can be regarded as coarse.