Wall roughness effects on pressure drops

Vangol · March 15, 2013, 03:20

Dear All,

I'm trying to calculate pressure drops in a straight pipe with CFX 14.0.
I simulated two different cases with SST turbulence model:
- in the first case I set Wall Roughness = Smooth Wall on the solid boundary;
- in the second case I set Wall Roughness = Rough Wall (Sand Grain Roughness= 3mm).

In the Post-processing I evaluated the pressure drop for the two cases and it resulted perfectly the same. How it possible?

Thanks in advance.

feizaghaee · July 12, 2013, 07:41

Hi.
I think it's related to your mesh near the wall. check it out.

March 15, 2013, 03:20	Wall roughness effects on pressure drops	#1
Vangol New Member - Join Date: Mar 2013 Posts: 3 Rep Power: 13	Dear All, I'm trying to calculate pressure drops in a straight pipe with CFX 14.0. I simulated two different cases with SST turbulence model: - in the first case I set Wall Roughness = Smooth Wall on the solid boundary; - in the second case I set Wall Roughness = Rough Wall (Sand Grain Roughness= 3mm). In the Post-processing I evaluated the pressure drop for the two cases and it resulted perfectly the same. How it possible? Thanks in advance. gk_uk likes this.

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July 12, 2013, 07:41		#2
feizaghaee Senior Member moein Join Date: Dec 2009 Posts: 132 Rep Power: 16	Hi. I think it's related to your mesh near the wall. check it out.