Problem with generating manifold geometry for importing into SimScale


I have a geometry that I want to import into SimScale but it is complaining about the geometry having gaps and self intersections (which it does). In my definition I have a BREP container before my MESH container in which you can see my Brep lines completely align on top of each other but when converted into mesh, my floor slabs and façade get triangulated differently which results into a non-manifold mesh beyond the point of being manually repairable. ( Ignore those big openings at the end of each tube, they can easily be closed in Blender)

I have tried every mesh cleaning components I could get my hands on and none seem to do the job, and merging vertices based on distance in a software like Blender gets rid of a lot of gaps ( not all ) but introduces a lot of self-intersection.

I appreciate any help, thanks. (37.1 KB)

Is there a tool that wraps all geometries inside an all encompassing surface? Something like vacuum suction bags.

That geometry looks simple enough that I think it should be possible to generate a clean mesh from the start, which is generally much easier than making a bad mesh and trying to clean it after.

First of all I see that the collection of Breps is not flattened and joined before meshing.
I also see there are a lot of Trim Solid operations where maybe you want Boolean difference?

Aside from that, It looks like everything is extrusions, so maybe instead of making solids and doing boolean operations on them (which are generally relatively slow and potentially problematic), you could do any difference operations on curves before extruding.

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Thanks for taking the time.

You mean I should generate my mesh sooner and try to modify the mesh?

I tried Boolean operations but ran into some problems and Trim Solid worked the first time so I kept it, I will try and work it out with the Boolean operations. But it seems to me that the problem is not with the Brep generation because ultimately I have a few points generating perfectly aligned NURBS curves that I’m extruding, the problem only begins when it gets converted into meshes. There must be a way telling Grasshopper: Hey, try to generate mesh vertices on these two objects as near to each as possible.