Learning Forum

[pmt22]

I am using K-omega SST model with heat transfer for pipe flow. I ran the simulation for y-plus value less than 1 and got the convergence now I am trying to get grid independency for my case but as I am refining the mesh y-plus value also decreases and I am getting a different result each time. so my question is how to approach grid independency for this case and what should be the lower limit of y-plus I should try.

regards

[DrAmine]

What do you mean by different results? How are you doing the refinement? Is it steady/unsteady?

[pmt22]

it is a steady axisymmetric flow. I am refining by decreasing the size of the element in radial and axial direction. my quantity of interest is wall temperature and there is a peak in wall temperature but as I am refining the mesh the peak value decrease rest profile remain the same. so my question is this normal and what is the minimum limit of y-plus I should go or whether for grid independency I should keep the y-plus constant and refine the bulk?

regards

pmt22

[DrAmine]

What happens if you keep increasing the mesh density? I do not want to comment in detailed fashion when it comes to refining a mesh using a RANS model. 

 

[pmt22]

Thanks for your reply. The wall temperature has a peak value that kept on decreasing when I increase the mesh density. can you name any source where I can look for this topic??

Regards

pmt22

[DrAmine]

Do you have data to compare with? What happens if you continue increasing mesh density? You look after Richardson extrapolation for grid independency study.