Error during meshing " Invalid boundary mesh (overlapping facets) on surface" "No elementsd in volume"

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zeke_stane
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Joined: Thu Jan 19, 2023 8:53 pm

Error during meshing " Invalid boundary mesh (overlapping facets) on surface" "No elementsd in volume"

Post by zeke_stane »

Hello,
I am trying to run an FEA analysis on a "rack" for rolls i am working on. I created the solid pieces using the "Sketcher","Part", and "Draft" workbenches and used "Part Fuse" to connect them. I then switch to the "FEM" workbench and after applying materials, constraints and loads i try to mesh the fused part. Netgen simply crashes and Gmsh reports the following error.

"Error : Invalid boundary mesh (overlapping facets) on surface 32 surface 37 Error : No elements in volume 1 Error : ------------------------------ Error : Mesh generation error summary Error : 0 warnings Error : 2 errors"

I am new to using this software and i looked around the forum for a solution to something similar. I tried a few suggestions i found (eg changing the min, max element size), however they didn't have any effect.

What am i doing wrong? I tried running a FEA to a pallet design i found online, and is created with pretty much similar steps (https://www.youtube.com/watch?v=uyHAVQc58Mk), and it meshes and produces results just fine.

Thanks in advance for any tips and suggestions and congratulations on this wonderfully helpful forum.

OS: Windows 7 Version 6.1 (Build 7601: SP 1)
Word size of FreeCAD: 64-bit
Version: 0.20.1.29410 (Git)
Build type: Release
Branch: releases/FreeCAD-0-20
Hash: f5d13554ecc7a456fb6e970568ae5c74ba727563
Python 3.8.10, Qt 5.15.2, Coin 4.0.1, Vtk 8.2.0, OCC 7.6.3
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NewJoker
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Re: Error during meshing " Invalid boundary mesh (overlapping facets) on surface" "No elementsd in volume"

Post by NewJoker »

Can you share the .FCStd file ?
zeke_stane
Posts: 5
Joined: Thu Jan 19, 2023 8:53 pm

Re: Error during meshing " Invalid boundary mesh (overlapping facets) on surface" "No elementsd in volume"

Post by zeke_stane »

Yes, of course.
PalletJr2_FEM.FCStd
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NewJoker
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Re: Error during meshing " Invalid boundary mesh (overlapping facets) on surface" "No elementsd in volume"

Post by NewJoker »

This geometry is invalid and can’t be meshed properly. You may have to change the modeling approach. You should get some help with that if you ask on the main help forum: viewforum.php?f=3
zeke_stane
Posts: 5
Joined: Thu Jan 19, 2023 8:53 pm

Re: Error during meshing " Invalid boundary mesh (overlapping facets) on surface" "No elementsd in volume"

Post by zeke_stane »

Thank you very much. So apparently my mistake had to do with the extrusions of the "triangle-shaped" solid on top of the base. If the side solids are drawn on a single sketch and extruded the meshers crush. If the solids are drawn and extruded separately it works just fine.
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