Week- 5 - Solid meshing

WEEK 5 CHALLENGE

AIM

To generate tetra mesh of the given model using ortho tria and tria elements followed by generating a volumetric mesh according to the required quality criteria.

PROCEDURE

• Geometry cleanup is performed on after which we can move on to tetra meshing.
• Check Geometry is performed to check for geometrical errors such as collapsed cons, etc.

Figure 1.

• It is observed that certain features may fail for element quality length, such features were defeatured using the dach option as shown in figure 2 and figure 3
  

Figure2.

Figure 3

• Now we can move on to the mesh generation.

MESHING

• After topology clean up, we can move on to meshing the model.

• First, we set the meshing criteria according to our requirements.
  The criteria are given in table 1
  

Criteria	Value
Element Length	1mm
Minimum length	0.5 mm
Maximum Length	2 mm

• We set the criteria accordingly in the mesh parameters tab and quality criteria tab.
• Elements % is enabled and the detail on demand effect is set to all details.
• We set the element type to ortho tria and first focus on the curved portions of the model.
• Using the length command we set the length to 1mm so that the element length across the mid surface will be 1 mm.
• Now we move on to meshing, we use the spot mesh option under mesh generation for this.
• It should be noted that ortho tria is preferred for curved portions and tria is preferred for flat surfaces for the sake of simplicity for solvers.
  

Figure 4

Figure 5

Figure 6

• The mesh is reconstructed/smoothed so as to solve the failed elements.
• After this, we now go to the volume mesh module.
• First, each part needs to have its volume defined separately (they may be in the same Psolid but 4 volumes need to be generated In this case)
• For volume meshing, we choose Tetra rapid and do this for each volume separately.
• The final meshed part is show in figure 19-23.
  

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Learning Outcomes

The following skills were learned and practiced during this challenge.

• Model Geometry Clean up
• Tetra meshing with ortho tria elements.
• Defeaturing using Dach
• Setting up Mesh quality criteria
• Generating Mesh with spot mesh criteria option
• Modifying Generated mesh to fix elements that fail the criteria along with opposite trias and rotating quads.
• Defining volumes for parts
• Tetra rapid meshing of defined volume
• Fixing collapse error in volume meshing.

Conclusion

The meshing of the given Rearview mirror component was performed following strict standards which were passed. After topology clean-up, the generated mesh was modified to correct element failures. After this, the volumes for the generated mesh were defined and tetra rapid meshing was performed on the defined volume.