SolidWorks Flow Simulation with and without Surface Roughness
Hi,
I've been using SolidWorks Flow Simulation to calculate KV value of a valve. I did two tests: one without surface roughness and one with it. Surprisingly, the results didn't change much (< 1%).
I was wondering if anyone else has used this feature and noticed whether surface roughness made a difference or not.
Thank you in advance.
Frane
Accepted answer
Hello Frane!
Although roughness generates a pressure loss, and the latter influences the Kv, the changes will not necessarily be very significant because perhaps the "equivalent length" of the valve is small. Changes in the velocity profile near the surface are to be expected (the fluid will tend to stick to the surface when there is roughness) but the overall flow may not change much!
The case is different if you have a very long pipe and you test it with or without roughness, since the pressure loss could be very large.
Perhaps you could take some tabulated values for pipes with different surface conditions (from very smooth and clean, to rusty and encrusted, very rough) and see if your simulations reproduce (at least in order of magnitude) the head losses expected for them ( which are usually very reliable because they arise from real tests). It would be a way to verify if you are proceeding correctly and can trust your CFD simulations.
Kind regards,
Marcelo
