Mesh generation failed 1

[ShadowWarrior]

When I mesh a small portion of the original structure, there is no problem (all hexahedral elements with no warning). Then I mirror the part to reach original structure size and the following message pops up while trying to mesh -
"Mesh generation failed due to a problem in the propagation of mesh seeds. Try to modify the meshing algorithm and the seeds."

Why is it happening and is there a way to solve this? Workstation is Dual Xeon (20 core) with 96GB RAM.

Appreciate the help.

 

[Dave442]

"The merged out nodes number is same for maximum tolerance just before shortest element edge length warning pops up."

Of course it does - your tolerance is huge (approaching the minimum element edge length). The problem is that the merged out node number doesn't match for a tight tolerance (1e-06). If everything is lined up perfectly it should. You should verify that you are only merging coincident nodes.

The Mesh gaps/intersections tool highlights element edges that either intersect the boundary faces or are in close proximity to unconnected boundary faces under a specified tolerance. You can use it to identify what regions aren't being merged with your tight tolerance.

 

[ShadowWarrior]

You can use it to identify what regions aren't being merged with your tight tolerance.

All looks same for 1e-6, 1e-5, 1e-4 and 1e-3 tolerances, still the number of merged out nodes varies.

 

[Dave442]

if the number of merged nodes varies it can't be the same...

attach your model.

 

[ShadowWarrior]

Okay, so I did a verification of the "increasing the tolerance until the warning pops up about tolerance exceeding shortest element edge length" method, and the result was satisfactory.

I created a small geometry by the Meshing -> Mesh part -> Instancing -> Translating -> Merging operation with 1e-6, 1e-5, 1e-4 and 1e-3 tolerances.
Then I created the same geometry just as a part, meshed it natively with the same element size and got the same amount of nodes with 1e-3 tolerances.

Does this prove the large tolerance approach?

I am unable to attach the actual model, apologies.

 

[IceBreakerSours]

I agree with suggestions provided above. I am not sure if this works with orphan meshes or geometric instances or both but try using face-to-face constraint in the Assembly module and then merging instances.

You can also check the coordinates of the "seemingly close enough" nodes (or the distance between them) and be sure about what the precise tolerance should be.

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[Dave442]

One more idea - your large assembly is made up of a single mesh instance that has been copied/mirrored/translated etc. You should be able to query the number of nodes on the different surfaces of the initial mesh instance to calculate exactly how many nodes should be merged out when generating the large assembly.