A Generalized Flow Simulation System
by
Roy P. Koomullil
Engineering Research Center, Mississippi State University
Coauthors: Bharat K. Soni

A flow simulation system for generalized grid will be presented. A generalized grid can be of structured, unstructured, any combination of structured and unstructured or cells with any number of cell-faces. A cell-face based data structure is used to store the grid information, which will help in handling cells with any number of cell-faces.

A finite volume, cell-centered scheme is used to solve the integral form of the full Navier-Stokes equations. The cell averaged values of the conserved variables are assumed to be stored at the cell-center and the numerical fluxes that cross the cell-face are calculated using upwind schemes. A flux difference split scheme by Roe and a flux vector split has been incorporated in the flow simualation system. Higher order accuracy in the spatial domain is achieved by using a linear reconstruction of the conserved variables, utilizing the Taylor's series expansion and Gauss theorem. During the reconstruction process, the creation of local extrema is avoided by the application of limiter functions. To predict the turbulent behaviour of the fluid flows, the turbulent viscosity is calculated using the one-equation turbulence model by Spalart and Almaras.

The implementation of the numerical schemes together with computational examples that are of practical importance will be presented during the conference

Date received: April 19, 1999