Week 5

Solid Meshing Or 3D Meshing

Objective : To clear the geometrical errors in the model and mesh the same in 3D.

Step 1 : The model is imported onto the ANSA GUI.

Step 2 : There are a few topological errors in the CAD model. They are cleared automatically from the check geometry.

Step 3 : After the topological errors have been cleared , Start meshing for the given quality criteria.

S.No	Quality Criteria	Value
1.	Target/Average length	1
2.	Minimum Length	0.5
3.	Maximum Length	2
4.	Tetcolapse	0.2

Step 4 : Since the model has no definite thickness and requires to be meshed in 3D tetra elements , the tria mesh is generated on the model without extracting any mid surface. The ortho tria elements were used on few fillets and on a few curved surfaces of geometry. The Ortho trias were used because it captures the mesh perfectly in such areas better than that of tria elements. The computational time for ortho trias is higher than that of trias elements.

Step 5 : To generate tetra mesh or Unstructured mesh from the generated tria mesh , the generated tria mesh should be defined i.e to generate tetra mesh , we need to specify the meshed component or model to be a closed volume.

To generate any volume we need to define a volumetric property.

When the model is defined ANSA will change the property ID of the model from P shell to P solids.

Step 6 : The components were defined and meshed with tetra rapid elements. Volumetric property any definite thickness. ANSA will start generating tetra mesh inside the tria mesh.

Conclusion :

• The model was cleared from all topological errors .
• The model was meshed 2D tria elements.
• 3D Tetra mesh was generated from the 2D tria elements on the surface.
• Errors such as tet collapse were cleared using “MV free” option from Grids module Buttons.