Rear mirror 3D Tetra meshing in Ansa

Objective : For the given component, check for the geometrical errors and mesh with the given element Quality criteria. Use tetra elements to model the component and there should not and kinks and dips on the surface of the component.

fig. rear mirror (model)

Procedure : There are four steps that we should follows.

1. Geometry cleanup.

2. shell meshing for surfaces.

3. Define volume meshing.

4. Quality check.

First import the cad model into ansa and then give topo for the entire geometry to join the edges and change the perimeter length to 1mm to visualise the geometry properly.

fig. after topo operation

1. Geometry cleanup : check for all the geometry or topological error by run a geometry check on whole geometry by going into checks>>geometry from the menu tool. this will show the geometrical error.

fig. geometry check (topological errors)

As you can see the triple cons and other geometrical errors are there . so we remove those error by auto fix or manually and then check the geometry again.

fig. rectify geometrical error

2. Shell meshing with tria element : after geometry cleanup .now we are moving for surface meshing.

now apply the mesh parameter and quality critria which are as followed.

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

here we mesh the entire geometry by spot mesh algorithm by choose tria or ortho tria options for a proper mesh flow.

ortho tria element are preferred for curved surfaces to achieve proper mesh flow and better feature capturing.

ater meshing check the quality errors . if found then rectify the errors formed by the element by shell mesh>>reconstruct or grids>>mv free command.

3. Define volume : before performing volume meshing ,it is checked that th geometry is a closed entity.

under volume mesh module define each and every part seperately by going volume>>define option.

fig. Manually define volume

After define volume go to the Volumes>>list shows unmesh part. Right click on it and perform Remesh>>tetra rapid or Tetra Fem. continue this operation for all the part.

4.Quality check : check for kins and raise on the surface and rectify them using MV free command.

Learning outcome :

1. learn how to do solid or volume meshing.

2. difference between tetra rapid or tetra Fem.

3. learn to clean collapsed element in the model.