Meshing 3D Volume (Inverted Elements !)

Use of the platform
1

Hello All,

I want to create a 3D mesh for a solid with geometries shown in the Figure using SALOME 9.12.0. The type of elements I want to use is Hexahedral like the elements shown in the Figure. The steps this mesh was created is as follows:

  1. The cross-section perimeter of the solid was drawn in the y-z plane using the Shaper module. Then, the surface was extruded along the x-axis to create an extruded 3D solid volume as shown in the Figure.

  2. The sketch was exported to GEOM (from features tab – export to GEOM).

  3. Using the Mesh Module, we created a mesh with the following options.

a. Select extrusion for Geometry.

b. Select Hexahedron (i, j, k) for 3D Algorithm.

c. Select Quadrangle: Mapping for 2D Algorithm.

d. Select Wire Discretisation for 1D Algorithm. Select Number of Segments for Hypothesis (e.g., a number of 15 segments was selected here).

e. Compute the mesh.

Question1: When I used the approach mentioned earlier, which is meshing the entire extruded volume, I had issues with the created mesh. It shows some inverted elements at the ends as shown in the Figure !!. Is there a way to resolve this issue?

Question2: Is it possible/better to create the 3D mesh by creating a 2D surface mesh of the cross section using quadrilateral elements, and then extrude the 2D elements along the third dimension (longitudinal axis) to generate a 3D mesh with hexahedral elements?

I appreciate your help

Regards,

Abdullah Al Rufaydah

Figure

FIGURE
FIGURE2255×2745 1.56 MB

MESH_v2.pdf (187.0 KB)

2

For q1. I think it is an issue of your workflow. You are doing a workflow where your geometry should be divided into blocks (6 faces 8 vertexes) and what you did should work.
For q2. Yes, you can create a face group in the geometry of one of the extruded faces (only one) then go to the mesh module create a 3d mesh with extrusion 3d, and also define 1d with what you want. And lastly you need to create a sub es on the face group and quadrangulate that. For this you can use gmsh algos, netgen with predominant quads or divide that face into quads in the geometry and use quadrangle mapping.