Learning Forum

[whbutc]

I'm using Ansys v19.2 and am having difficulty getting a hex mesh in the area between two very close holes that are perpendicular to each other.  I am required to use a hex mesh for the model.  I am able to get a nice hex mesh for all of my partitions except the very last one which is the blind hole running close to the through hole.  I've tried all kinds of partition ideas and mesh methods/sizings with no luck.  Here's the approach that seems to get me the closest.  I use multizone to get a nice hex mesh on all of the partitions except the blind holes.  On the through hole partition nearby, I get a hex mesh, but even though it has a shared face with the blind hole partition, it doesn't account for the nearby hole at all when it meshes.  Because of this, I can't get the last partition to give me a hex mesh.  It seems like it is so close, but I can't figure out how to get the last issue resolved.  I pulled the part out of my assembly and created a simplified dummy model of just the area in question and created a new analysis.  The .wbpz file is attached.  I am new to Ansys so any help at all would be greatly appreciated whether it is solving the last piece of the puzzle or starting over with a completely different approach.  Thanks in advance. 

[peteroznewman]

I recommend you create a plane on the orange face, then Split all bodies with that plane.

In ANSYS 2019 R3, I used the Workbench tab and clicked on the Share button and I think the Shared Topology is going to let the mesh be connected.

[whbutc]

Peter, thank you for your reply.  I finally got to try out your suggestion this morning, but am still having the same issue.  I am able to share all of the topology in spaceclaim, but have the same issue when trying to mesh in mechanical.  I'm not sure if it has something to do with the source selection within the multizone method or with the order of how I'm meshing the partitions.  It seemingly keeps wanting to ignore the shared topology.  It even appears to have done it along the new cut now.

 

[whbutc]

Update: for some reason after the new slice, Spaceclaim tells me it found and shared the topology but then it doesn't show up when I turn on connectivity.  I went back to the previous model and tried it again.  The shared topology appears to have worked this time, but the mesh still isn't working for me.

 

[peteroznewman]

I was using a newer version of ANSYS than you so it may have worked better for me, you might have to do some more work.

I recommend you take a circle that generates the cylindrical surface adjacent to the orange face I showed above.  Use a cylindrical surface with a length longer than the thickness of the ring so it sticks out both ends. Then use that cylindrical surface to slice all the bodies.  That will make a large number of six-sided bodies that will mesh with Hex elements.

After that, we can address the special circumstances around the blind hole.

[whbutc]

I spent some time today and upgraded to 2019 R3 to see if that made a difference for me.  It picked up the shared topology for the blind hole, but I still couldn't get all of the partitions to mesh.  I must have some settings different that's causing it not to work like yours.  Then I attempted the additional slice you recommended.  With the exception of a couple of partitions that I think I can probably fix, everything meshed just fine except for the highlighted area below.  It didn't want to mesh even if I started there.