Learning Forum

[AnneSophie]

Hi,

I am working on a 2D mesh of a building in Ansys Meshing. I used inflation to create the boundary layer mesh and face sizing to create an unstructured quadrilateral core mesh. I have 2 questions regarding this mesh.

First, I wonder how I can efficiently create a smooth transition from the inflation layer to the core mesh? I spent quite a lot of time adjusting the growth rate and maximum amount of layers in the inflation to get a more or less smooth transition. I used first layer thickness as the inflation option, because I want to be able to control the first layer height. Is there a better/more efficient way to create the smooth transition?

My second question is about mesh refinement. How can I easily refine/coarsen the mesh described above to perform a mesh independence study, while keeping the first layer thickness constant and the transition from boundary to core smooth?

I would greatly appreciate your advice!

[Rob]

I tend to use inflation - smooth transition. First layer is only really useful if you think you know the flow speed and have used a y+ calculator.  More layers may help as can edge sizing: you'll need to figure out what edge size can transfer from the inflation layer to the volume mesh. 

Refinement is probably best checked using adaption. You can do that in Fluent and it saves all the hassle of remeshing. This will alter the near wall mesh, so you'll need to decide whether this is a problem. 

[AnneSophie]

Thank you for your response, rwoolhou. I tried the smooth transition option, but in my case this made the transition to the core mesh even less smooth (even if I changed the sizing, growth rate and the number of layers). Also, I have a lot of problems with skewness in the corners of the boundary layer mesh. I decided to switch to ICEM CFD, to have better control over the boundary layer mesh.

[fanaticreader95]

If you want to do that, I think using edge sizing with a specified bias may work bettern

[Keyur Kanade]

Please change transition ratio. Please go through help manual for details about transition ratio. nAlso giving edge sizing will also help to get good transition. nRegards,nKeyurnGuidelines for Posting on Ansys Learning ForumnHow to access ANSYS help linksnn