I do not know about it

You can define the roughness value while defining boundary condition for Micro-channel wall.

 Dear Vikas

Thanks for your answer. I tried, but as I know the roughness option is active only for the turbulence flow ranges.  

Hi Davaood

You are simulating Laminar flow but the effect of wall roughness is generally ignored for such flow conditions thus in FLUENT the wall roughness definition is disabled for laminar flow. However, you can write some user defined parameters to account wall roughness effect.

Go to Boundary conditions> Select Wall> Select parameter (from the 1st column and 2nd row at the bottom)> Create> User defined> New parameter. 

Hi Daver,

Can you please let me know whether you've found a way to account for the wall roughness impact on a laminar flow? Thanks in advance.

Regards,

Ahmed

Dear Ahmed,

I modeled roughness elements physically in Ansys APDL and then sent it to fluent. Please refer to our recent work on this topic.

Article Computational Fluid Dynamics Study of the Effects of Surface...

Bests,

Daver

Dear Daver,

I'm quite thankful for your immediate reply and valuable advice.

Regards,

Ahmed