Performing Mesh Cleanup on 2D SHELL Elements

OBJECTIVE

1. To perform the geometry cleanup operation on the given 3 files and to extract and apply mesh to the 2D shell elements under the given criteria.
2. The given geometries are:
   1. Practice
   2. Clip Repair
   3. Mounting Bracket
3. Operations to be carried out:
   1. Clean the geometry.
   2. Extract midsurface.
   3. Clean midsurface geometry.
   4. Ignore holes less than dia 5mm.
   5. Create 2D mesh with target length 5mm, min 3.5mm max 7mm.
   6. And assign proper thickness, by creating a generic property
4. Followed Criteria:
   1. No free edges
   2. convert all of them into refine geometry
   3. Create 2D mesh with target length 5mm, min 3.5mm max 7mm
5. Properties to be applied:
   1. To create a generic property to assign proper thickness

GIVEN GEOMETRIES:

1. PART 1: CLIP REPAIR
2. PART 2: PRACTICE
3. PART 3: MOUNTING BRACKET

PROCEDURE:

• The given geometries (in .hm format) are imported to hyperworks software.
• The geomerty cleanup operations are performed to make sure that the given geometry is a completely closed volume.
• After the completing the geometry cleanup operations, the mid-surface is extracted from the closed geometry.
• The cleanup operations used are:
  • toggle edge
  • filler surf
  • add/remove points
  • replace points
  • unsplit surf
  • delete surf
  • surface trim
• The extracted mid-surface is the 2D shell element on which the meshing is applied.
• Automesh option is used to mesh the shell element after the successful cleanup of the mid-surface.
• Automesh option is used from face to face of the shell element to maintain the flow and to satisfy the given criteria.
• Elements were mirrored using the Reflect option to make the process simpler and fasted.
• The equivalency was checked and the elements were made equivalent under a certain tolerance value.
• Holes having less than dia 5mm were ignored.
• The criteria file settings were change to satisfy the given conditions.
• The minimum element size was set to 3.5mm and the maximum element size to 7mm, the target value was set to 5mm.
• Remeshing was done to the elements to satisy the given conditions.
• Smooth option was used to improve the element flow.
• Smaller surfaces are ignored to maintain the element flow and size.
• Quality check is done to ensure that the elements are under the given criteria.
• Created a generic property to assign a thickness of 1mm.

Extracted Midsurface (2D shell element)

1. Part 1:
2. Part 2:
3. Part 3:

Meshed geometry

1. Part 1:
2. Part 2:
3. Part 3:

Criteria File Settings:

Element Equivalency Check:

1. Part 1:
2. Part 2:
3. Part 3:

Element Quality Check:

1. Part 1:
2. Part 2:
3. Part 3:

Applying Thickness:

1. Part 1:
2. Part 2:
3. Part 3:

Gdrive links for the .hm files: https://drive.google.com/open?id=1kd_UBzh6I-6LUpkgxR-x_3_7zHUMb2Qy

RESULTS AND CONCLUSION:

• The given geometries (.hm files) were successfully imported to the hyperworks software.
• The geometry cleanup, mid-surface extraction and mid surface cleanup operations were completed successfully.
• The element size was set to minimum size 3.5mm, maximum size 7mm and target size 5mm.
• Element equivalency check has been completed with zero errors.
• A generic property was created to assign a thickness of 1.
• The element quality check was completed successfull with zero elements crossing the given critirea.
• The minimum element size shown in the quality check is 3.5mm and the maximum size shown is 6.9mm which are under the given boundary.
• To conclude, this excercise was completed successfully and the usage and working of various tools and operations were studied and performed.