[cfMesh] surface patches feature edges not preserved

robboflea · April 8, 2019, 11:55

Hi all,

I am using cfmesh since a few days and I am having an issue with the shape of feature edges on surface patches.
My domain is very simple. It's basically a parallelepiped with a rectangular inlet on a part of a face and a rectangular outlet on a part of another face.

I am having an issue with the conservation of the shape of the inlet and outlet patches after meshing. I did run:

Code:

surfaceFeatureEdges -angle 45 domain.stl domain.fms

this runs correctly. The feature edges are correctly recognized and I can see them in paraFOAM. The issue is that, while right angles are conserved in the mesh for all the edges of the parallelepiped, they are not preserved at the inlet and outlet boundaries. Below you can see an image of the inlet patch after meshing.

Screenshot from 2019-04-08 15-19-36.png

Anyone has any idea why this is happening? While trying to debug the meshing process using workflowControls I can see that the first problems start to arise after the surface projection step.

Thanks a lot for the help!

Krao · May 16, 2019, 03:24

Hi Robboflea,

Can you please post your meshDict, it looks like the refinements at the edges are not defined. If you want to have sharp edges without defining any refinement, you can use surfaceAutoPatch. If you have already solved your problem please let me know your solution, so that it can be impleamented in the future work. Thank you.

JoaoDMiranda · March 3, 2020, 05:23

Hello.
I am facing a similar problem.
Did you find a solution?
Thanks a lot

charlliemarshalll · June 14, 2020, 11:52

got the same problem, the inlet / outlet shapes are not preserved. I transferred the .obj files created by FreeCAD

April 8, 2019, 11:55	surface patches feature edges not preserved	#1
robboflea Senior Member Join Date: Nov 2011 Posts: 109 Rep Power: 14	Hi all, I am using cfmesh since a few days and I am having an issue with the shape of feature edges on surface patches. My domain is very simple. It's basically a parallelepiped with a rectangular inlet on a part of a face and a rectangular outlet on a part of another face. I am having an issue with the conservation of the shape of the inlet and outlet patches after meshing. I did run: Code: surfaceFeatureEdges -angle 45 domain.stl domain.fms this runs correctly. The feature edges are correctly recognized and I can see them in paraFOAM. The issue is that, while right angles are conserved in the mesh for all the edges of the parallelepiped, they are not preserved at the inlet and outlet boundaries. Below you can see an image of the inlet patch after meshing. Screenshot from 2019-04-08 15-19-36.png Anyone has any idea why this is happening? While trying to debug the meshing process using workflowControls I can see that the first problems start to arise after the surface projection step. Thanks a lot for the help!

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May 16, 2019, 03:24		#2
Krao Senior Member Kmeti Rao Join Date: May 2019 Posts: 145 Rep Power: 7	Hi Robboflea, Can you please post your meshDict, it looks like the refinements at the edges are not defined. If you want to have sharp edges without defining any refinement, you can use surfaceAutoPatch. If you have already solved your problem please let me know your solution, so that it can be impleamented in the future work. Thank you.

March 3, 2020, 05:23		#3
JoaoDMiranda New Member João Duarte Miranda Join Date: Jan 2012 Posts: 13 Rep Power: 14	Hello. I am facing a similar problem. Did you find a solution? Thanks a lot

June 14, 2020, 11:52		#4
charlliemarshalll New Member Charlie Marshall Join Date: Jan 2020 Posts: 17 Rep Power: 6	got the same problem, the inlet / outlet shapes are not preserved. I transferred the .obj files created by FreeCAD