CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   CFX (http://www.cfd-online.com/Forums/cfx/)
-   -   suggestions for turbulence model (http://www.cfd-online.com/Forums/cfx/26695-suggestions-turbulence-model.html)

Li November 19, 2008 15:38

suggestions for turbulence model
 
Hi, I am trying to get the details of boundary layer as much as I can, so I'd like to use Low-Reynold k-e turbulence model, but I cannot find it in CFX. Thank you.

Regards, Li

Toralf November 20, 2008 03:10

Re: suggestions for turbulence model
 
Hi Li,

you cannot find the list of turbulence models? double-click on any domain and choose a model from the pull-down menu in "fluid models". the model than is valid for all domains. good luck.

Li November 20, 2008 03:47

Re: suggestions for turbulence model
 
Hi Toralf,

Thank you for the post. I can find the list of turbulence models, but I cannot find low-Reynold k-e turbulence model.

Toralf November 20, 2008 04:16

Re: suggestions for turbulence model
 
Hi Li,

i have never heard about specific low-reynolds k-e model. you can find in solver modeling guide k-omega is recommended for low-reynolds numbers as well. in my list of turbulence gives no low-reynolds number k-epsilon model. maybe others can help. greetings

John S. November 20, 2008 12:08

Re: suggestions for turbulence model
 
CFX uses automatic wall treatments in its turbulence modeling based on your grid y+. For resolving a boundary layer simulation I would probably use the SST model. If your grid has an adequate inflated boundary it will automatically employ a low Re wall treatment.

Li November 21, 2008 04:44

Re: suggestions for turbulence model
 
Hi Toralf and John, thank you for the post. I ever tried SST model in room ventilation simulation, but the results is not in good agreement with the benchmark test data. I am sure the grid is good enough in the benchmark test simulation and I also checked the output file to see the converstation balance and it converged well . So that's why I worried to use SST model.

What I am doing now is to simulate a square wind tunnel to study the gas emission from the surface. I need to solve the boundary layer. I will try to use SST model and if you have any suggestions, please tell me. Thank you!

Regards, Li


All times are GMT -4. The time now is 03:41.