CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   FLUENT (http://www.cfd-online.com/Forums/fluent/)
-   -   High speed flows (http://www.cfd-online.com/Forums/fluent/39092-high-speed-flows.html)

Raj December 31, 2005 04:37

High speed flows
 
Hi,

Somebody help me to model the high speed (Mach >3) flow in CFD..i try to simulate the Missile FLume studies by cold flow approximation it is not at all converging..i heard that for high mach flows, Density based algorithms would work better than Pressure based algorithms ..it is true?..if it is, then FLUENT is having Density based alogithms? i also want to know Fluent is having ROE's Schem, Van Lear and kinietic based alogithms for solving high speed compressible flows like super sonic and hypersonic..

We tried the same probs in CFD-FASTRAN (Cold flow simulation) we got some good solution...the reason for that it is having DENSITY based alogithms and i have a option of selecting ROE or VANLEAR scheme, because i thing those scheme have robust to predict the shock in high speed regime compared to other scheme like relaxation etc.. ...but the same thing i am not able to get in FLUENT (that is ROE or VANLEAR Option)..i thing may be the algorithm in FLUENT is RELAXAION Based only ...]

Thanks for ur help...

Rajavel B

veinan January 1, 2006 08:34

Re: High speed flows
 
In Fluent6.3 you can select FDS-ROE or AUSM

Raj January 9, 2006 09:15

Re: High speed flows
 
Thanks veinen...

but i thing this (FDS-ROE) is FDM based instead of FVM right...but i want FVM-ROE scheme...

Rajavel

S K Prasad January 10, 2006 00:43

Re: High speed flows
 
There is nothing like FVM Roe. Actually FVM is the way you discretize the governing equations to obtain a set of discrete equations for each control volume in the computational domain. Now in FVM, the rate of change of any quantity in a control volume is equal to flux crossing its boundaries. This flux consists of inviscid and viscous flux. To calculate the inviscid flux an array of schemes are available like Roe, AUSM, Van Leer, KFVS(kinetic scheme) to name a few. FDS stands for flux difference splitting and not finite difference scheme.

raj January 10, 2006 05:14

Re: High speed flows
 
Thanks Prasad,

I thought it is Finite DIfference Scheme...yes i also learned abt Flux Difference splitting,AUSM,Peculier velocity based Kinetic Scheme etc..in compressible flow alogrithms....i will try for my future modeling....

Thanks once again...

Rajavel...


All times are GMT -4. The time now is 15:30.