[Lucky Luka]

Hi all
Can someone explain me why the number of prism layers decrease where I have the curvature?
How can I improve this situation?
Cheers

[bluebase]

Hi Luka,

in your case, the prism layer is reduced because it is approaching the interface. The interface has been set to not receive a prism layer.

Please review the manual, what the boundary marching angle, concave angle limit, and convex angle limit do for the prism layer mesher.

Do you need these interaces at the location they are now?

Best regards,
Sebastian

[ashokac7]

Originally Posted by Lucky Luka

Hi all
Can someone explain me why the number of prism layers decrease where I have the curvature?
How can I improve this situation?
Cheers

In prism layer set up, make Layer reduction percentage zero from default value of 50.
Note that the layers will be compressed near proximity surfaces so you will have very small prism layer thickness there.

[Lucky Luka]

Hi all
Is this the right layer properties section? I've found it under the mesh model.
I haven't understood how to change the settings in order to improve my situation.

[ashokac7]

Originally Posted by Lucky Luka

Hi all
Is this the right layer properties section? I've found it under the mesh model.
I haven't understood how to change the settings in order to improve my situation.

Keep your minimum thickness realistic. 0.01% of prism layer thickness is very small if you ask me. keep it atleast 10%. So if prism later thickness is 1mm then you will atleast have 0.1 mm thickness where curvature is complex. Keep layer reduction percent zero if you don't want any reduction in number of prism layers.


Hope this helps.

[bluebase]

Originally Posted by Lucky Luka

I haven't understood how to change the settings in order to improve my situation.

Hi Luka,

did you got a chance to read the manual on "Prism Layer Model Expert Properties"? It describes most of the available settings with images.
In v13, you can find this page in this branch of the manual:
Pre-Processing > Meshing > Volume Meshers > Prism Layer Mesher > Prism Layer Model Expert Properties

If i understood your question correctly, you are interested in why the boundary layer at the "tip" of the fan retracts to zero at the interface. Is this meaning correct?

In that case the boundary march angle will be the most important parameter. You most likely have to increase it. The manual will explain why.
The layer reduction parameter is described as well. It helps to mesh tight corners. For other high curvature corner's the Near Core Layer Aspect Ratio might have an impact in your mesh, too.
For internal interfaces it is helpful to change the interface's source surface to the symmetric type (or any other non-wall type), so the mesher recognizes it does not need to retract the prism layer if it is approaching such interface boundary.

It is probably a good investment for you to read and understand the whole section on the prism layer mesher.