Hi All,

I wish to know the difference between pressure based solver(eg. star-CD) and density based solver(Fluent). As far as I know both of them use finite volume formulation and use spatial and temporal discritisation(usually implicit)and then use pressure correction schemes(SIMPLE,SIMPISO or PISO) to convert non-linear system of algebraic equations to linear system of equation. These equations are then solved iteratively using Conjugate gradient method or multi grid techniques.

DB

fluent also has pressure based solver which is exactly same as starCCM+ as far as theory is concerned, i am not sure about the implementation differences.

StarCCM+ is density based solver, again people say but I dont know what is the difference between density based solver and pressure based solver.

DB

StarCD has the quit normal pressure based solver (segregated solver), which has some stability problems at high mach numbers because of density variations (mach < 1). That's NOT a problem of the solver implementation in star. That's the native of the solver-numeric !!!

StarCCM+ has a coupled solver (velocity and pressure), which has some stability advantages concerning high mach numbers (mach < 1). But I think it is still pressure based.

A real solver for compressible flows (mach > 0.3 and possibly > 1) is a density based solver like the "Rieman-Solver". I don't know if FLUENT uses such a solver.