3D extruded mesh problem for round conductor

Yangyu Sun

Dear Flux community,

I am now building a 3D model by extruding the 2D geometry with associated mesh generator. The aided mesh is deactivated and all the mesh information is defined and assigned to the geometry manually in 2D to avoid problems in 3D modelling. My problem is that, the mesh for round conductor in 2D is OK (the mesh is uniform), but when I extrude the geometry in 3D, the mesh of the round conductor becomes un-uniform, which is not acceptable.

The difference between 2D mesh and 3D mesh is attached, the diagrams only illustrate mesh  of X-Y plane (Z direction has structured mesh so it is not shown here). I can also attach this flux file if necessary. Thanks for your help.

Mohammed Elamin_22169

Yangyu Sun said:

I have done everything I could do with respect to mesh settings (including change face mesh setting, volume mesh setting, using mesh points, use different kinds of mesh line, and use half aided-mesh and half manual mesh) and they all doesn't work. I think the geometry is correct. One thing I found interesting early today is the segmentation in axial direction (the volume are created by extrusion of face), If I have a relatively high number of segments in axial direction, the round face mesh will be less un-uniform, maybe that is helpful for you.

the attached model is a simplified model that I built in a few mins but it is representative, you can just have a look at the mesh of round conductor region. BTW, if you mesh the model you can find the strange behaviour of the mesh in round conductor. The mesh was OK in 2D.

 

THX a lot !

Hi, 

It seem like there is an issue with the relaxation inside the round faces. The aided mesh is inactive which means there no relaxation at all in all the faces. Typically it should work. 

Now to solve this either activate the aided mesh or just force some relaxation on the original round face (face (2)). you can even force the relaxation to null and it seem to work fine. 

Thanks,    

Mohammed Elamin_22169

Hi Yangyu, 

This is strange behavior and it shouldn't happens. Not sure what lead to such problem, Are you sure the geometry is correct. 

Did you try to force some mesh control on this round face again? if not try to do this on the 3D model and see it it works. Otherwise, you can share your project, if you do not wish to share it here. Please create a support ticket. 

Thanks,  

Yangyu Sun

Mohammed Elamin_22169 said:

Hi Yangyu, 

This is strange behavior and it shouldn't happens. Not sure what lead to such problem, Are you sure the geometry is correct. 

Did you try to force some mesh control on this round face again? if not try to do this on the 3D model and see it it works. Otherwise, you can share your project, if you do not wish to share it here. Please create a support ticket. 

Thanks,  

I have done everything I could do with respect to mesh settings (including change face mesh setting, volume mesh setting, using mesh points, use different kinds of mesh line, and use half aided-mesh and half manual mesh) and they all doesn't work. I think the geometry is correct. One thing I found interesting early today is the segmentation in axial direction (the volume are created by extrusion of face), If I have a relatively high number of segments in axial direction, the round face mesh will be less un-uniform, maybe that is helpful for you.

the attached model is a simplified model that I built in a few mins but it is representative, you can just have a look at the mesh of round conductor region. BTW, if you mesh the model you can find the strange behaviour of the mesh in round conductor. The mesh was OK in 2D.

 

THX a lot !

Mohammed Elamin_22169

Yangyu Sun said:

I have done everything I could do with respect to mesh settings (including change face mesh setting, volume mesh setting, using mesh points, use different kinds of mesh line, and use half aided-mesh and half manual mesh) and they all doesn't work. I think the geometry is correct. One thing I found interesting early today is the segmentation in axial direction (the volume are created by extrusion of face), If I have a relatively high number of segments in axial direction, the round face mesh will be less un-uniform, maybe that is helpful for you.

the attached model is a simplified model that I built in a few mins but it is representative, you can just have a look at the mesh of round conductor region. BTW, if you mesh the model you can find the strange behaviour of the mesh in round conductor. The mesh was OK in 2D.

 

THX a lot !

Hi, 

It seem like there is an issue with the relaxation inside the round faces. The aided mesh is inactive which means there no relaxation at all in all the faces. Typically it should work. 

Now to solve this either activate the aided mesh or just force some relaxation on the original round face (face (2)). you can even force the relaxation to null and it seem to work fine. 

Thanks,    

Yangyu Sun

Mohammed Elamin_22169 said:

Hi, 

It seem like there is an issue with the relaxation inside the round faces. The aided mesh is inactive which means there no relaxation at all in all the faces. Typically it should work. 

Now to solve this either activate the aided mesh or just force some relaxation on the original round face (face (2)). you can even force the relaxation to null and it seem to work fine. 

Thanks,    

The problem is now solved !!! I followed your advice and create a new relaxation face and then assign this relaxation face to the bottom round conductor face region. The mesh is now uniform across the whole axial length. Thanks for you help!