Week- 5 - Solid meshing

1. AIM
The aim of this challenge is to check for the geometrical errors of the 3D model of a
'Rearview mirror' and mesh with the given element quality criteria using tetra elements to
model the component.

2. Import the model:

file>open> disc> folder (downloaded model )

3. CAD CLEAN UP
As shown in Figure , the CAD model of the Rearview mirror is shown where the surfaces
are not attached to it its adjacent surface and single cons can be visible. Using the 'TOPO'
command the faces are stiched together removing all the single cons which is shown in
Figure

The CAD model had some unwanted triple cons and needle faces issue which were fixed
using auto fix option.

4. MESH GENERATION

Following steps were used to generate the solid mesh using Tetra elements after CAD clea
up process:
a) The quality criteria was assigned and the average element length was defined as given
below:

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

b) The CAD model was refined using 'Length' option from the MESH deck with a perimeter
size of 1.
c) Curved surface were meshed using 'Ortho Tria' elements to capture the curved face
more precisely and plane surface were captured using 'Tria' elements which can bee seen
in Figure below

d) All the off elements which were failing for maximum length and minmum length were
being solved using 'Reconstruct' option. Figure 3.2 shows no off element on the surface
mesh.

d) New PIDs were defined for the four different parts of the model. (Command Path =
V.Mesh>Volumes>Define)
These new PIDs for solid were meshed using 'Tetra Rapid' algorithm which does the volume
meshing faster without following the mesh pattern used in the surface meshing

S.No	Quality Criteria	Value
1	Tet collapse	0.2

conclusion

It was also noticed that the volume mesh can't be generated if the geomtery is open. So
the geometry has to be closed. Another important thing which has to be taken care of is
the meshed surface should be without any kinks and dips after meshing which was
achieved in here clear the Tet collapse quality criteria.

Result:

Tetra volumetric mesh is done with all quality criteria.

note: i have attached the ansa file along with this report