CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   FLUENT (https://www.cfd-online.com/Forums/fluent/)
-   -   Turbulence (https://www.cfd-online.com/Forums/fluent/163239-turbulence.html)

dale154 November 25, 2015 15:11

Turbulence
 
Hi, i have tested two turbulence models and just have a question about differences in solution.
I am modelling flow through a 2D compressor cascade.
Firstly i use k-omega turbulence and get a converging solution, however pressure values seem quite high.
However for some profiles i can't get a converging solution so i try SST-Transition and get a converging solution.
From this Pressure values seem more reasonable and velocity values are similar to that of the k-omega results.
I was wondering if anyone had any ideas on the differences observed between the two models?

(Note. 2D steady model, compressible, transonic flow with periodic boundaries).

I hope this is clear.
Thanks,
Dale.

CFDYourself November 25, 2015 16:01

hi dale,
The k-w model and the SST model are similar. the SST model blends the k-w model at the wall, and uses k-e model in the bulk. this plays to the strengths of the two models; k-w allows the flow to solve the boundary layer without relying on a wall function, while k-e model is more stable than k-w in the bulk.


All times are GMT -4. The time now is 18:30.