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Ansys Learning Forum › Forums › Discuss Simulation › Fluids › resolution boundary layer › Reply To: resolution boundary layer

September 12, 2024 at 6:45 pm
ggege0524
Subscriber

Hallo again, 

thank you very much for the answer. my mesh looks like below. when I check element quality, a column with element quality less than0.1 is displayed, and when I select it, only inflation layers are displayed. Skewness and aspect ratio are also a problem, especially at the inclined part.
 
also I had another question, I read the ANSYS User Guide for Near-Wall Mesh Guidelines (Section 12.3.1) and it says:
"In summary to achieve the best results with the Spalart-Allmaras model, one should use either a very fine near-wall mesh (on the order of $y_{\rho}^+ = 1$ for the first near-wall cell center ) or a mesh with $y^+ \geq 30$", but I don't understand something.
 
according to this, I can either use a very fine mesh, for example with Inflation layers and then  y+ should be <1 or I can remove the layers and have a coarse mesh but y+ must be between 30 and 300. Did I understand it correctly? Furthermore, what is y+_rho?