[Abhinand]

Hi,

I want a suggestion to find a way to disable the wall functions in fluent.
For RSM:
There is no way to write user defined wall functions, so is there a way to disable wall functions by changing the wall boundary condition to something else and mimic a wall but making fluent not to use wall functions?

For k-w model
There is a way to write user defined wall functions. How would you formulate to create a case where there is no wall functions?

Please suggest ideas to work around this issue.

Thanks

-Abhinand

[vinerm]

What's the objective behind disabling the wall function?

[Abhinand]

To see how the fluent solution would change if there is no wall function.

Let's assume you have an extremely fine grid. The use of wall functions does not matter since, fluent will not use it anyways coz of the grid. But when you do a coarser grid, you observe changes in solution but that includes the added effect of a wall function.

I want to see the change due to grid sizes without the effect of wall functions as a comparitive study of grid sizes

Thank you

[vinerm]

One solution is to use three (or two in 2D) UDS to represent momentum field. Another alternative, untested of course, is to use scalable wall function and modify the value of . Current value is 11.2247. You can change it using command

(rpsetvar ke-yplus-udf new-value)

where new-value should be replaced with new value that you wish to use for . Do note that Fluent uses instead of .