CFD Online Discussion Forums

CFD Online Discussion Forums (
-   Main CFD Forum (
-   -   roughness condition (

James August 11, 1998 08:34

roughness condition
I am using fluent code and want to know how can i give surface roughness condition in this code. Thanks, James

oliver August 12, 1998 08:11

Re: roughness condition
In order to model wall roughness, you must enable the wall roughness parameters such as height etc., in the graphic user interface. When the boundary conditions [i.e. for the wall normally W1] are been set you should be able to set the wall roughness constants.

Hope this is helpful

Sung-Eun Kim August 25, 1998 21:20

Re: roughness condition
Dear customer,

Glad to see you here James, but at the same time I'm sorry you posted your query here.

In our structured version of code, FLUENT 4.4, the roughness is specified using the constant ELOG. The users guide is the best source for detailed information on how to compute ELOG.

In the FLUENT/UNS4.2 or FLUENT 5 (the upcoming release), you can either directly specify the constant ELOG or specify the actual roughness height. The latter method is much more user-friendly and makes more sense because you don't need to estimate the wall-shear stress in advance to compute the k+.

Since someone asked about this in this forum, I wonder if you can specify different roughnesses for different walls.

If you have further questions, please email me or your support engineer, whoever you feel comfortable.

Sung-Eun Kim

All times are GMT -4. The time now is 08:23.