Cannot create volume mesh
Hello all,
I am trying to create a volume mesh of a ship. There is no special requirement on the mesh size and quality as it will be an input to a CFD solver with a background staggered grid so the geometry mesh only has to covers the whole geometry.
I received an .igs file of a ship hull which contains a lot of surfaces. There is a layer in the IGES which I don’t need (container on top of ship), therefore I removed that and closed the geometry in rhino and I was able to create a closed geometry without any naked edges.
I tried two methods creating volume mesh in gmsh. First was to create a surface mesh from the model in rhino, either with rhino tool itself creating a mesh and export to stl that or directly export the geometry. After, in gmsh I can create a volume from the closed imported surfaces using the following geo file:
Merge "6570TEU.stl";
Surface Loop(1) = {1};
Volume(1) = {1};
but when creating volume mesh I get the error:
Invalid boundary mesh (overlaping facets on surface 1 surface 1 No elements in volume 1
In rhino I checked the mesh and there was no overlapping elements so I don't understand where does this come from. I also checked and there are no non-manifold edges, degenerate elements. Is there other things I need to considered?
The second method I tried is to import the modified .igs but then I cannot even create a volume from the imported geometry. I can create a surface mesh, but than when I try to use that as an input and create a volume from it I cannot.
What would be a good way to get a volume tetrahedron mesh for this geometry?
I attached both the original igs, modified igs (without the containers), and the stl file.
6750TEUcontainership-scale1_65-breakwater.igs 6570TEU_modified.igsv 6570TEU.stl