3D Meshing Of Components

OBJECTIVE: Create 3D mesh on the given models with required quality parameters

MODELS: The models given in this task can be seen below

1. Housing Component

   2. Chassis Component

    3. Tetmesh Component

PROCEDURE:

1. IMPORT MODELS IN HYPERMESH
2. GEOMETRY CLEANUP
3. GENERATING 3D MESH
4. CORRECTING MESH FOR OPTIMUM QUALITY

IMPORT MODELS IN HYPERMESH

Models are generally imported into hypermesh through the import tab. Depending on the type of file ( STEP, IGES ), the geometry is imported. All models in the task were either STEP or  IGES. Imported models can be seen above in the model decription.

GEOMETRY CLEANUP

1. Housing Component

After this model was imported , the model was pretty good and not much errors or unequivalenced edges was present. The cleanup done hear was to prepare the housing component for meshing with miinmum element size of 2mm and maximum of 7mm. Using F4 (DISTANCE) points on the geomety was measured and all the lines lesser than 2mm was either toggled or corrected by merging and replacing points. This is done to prevent elements failing after meshing.Below is an image of the final cleanedup model.

    2. Chassis Component

After this model was imported , the model consisted of 8 components was pretty good and not much errors or unequivalenced edges was present.

This model consisted 4 components with mirror componets of it at the opposite side.

The cleanup done hear was to prepare the housing component for meshing with miinmum element size of 2mm and maximum of 8mm. Using F4 (DISTANCE) points on the geomety was measured and all the lines lesser than 2mm was either toggled or corrected by merging and replacing points.All fillets below 2mm was removed by moving points. Below is an image of component 4 with removed fillets and teeths which falls below 2mm.

The teeths were removed by trimming that part out ,masking it then deleted. The surface was extended after.

    3. Tetmesh Component

After this model was imported , the model was pretty good and not much errors or unequivalenced edges was present. The cleanup done hear was to prepare the housing component for meshing with miinmum element size of 2mm and maximum of 7mm. Using F4 (DISTANCE) points on the geomety was measured and all the lines lesser than 2mm was either toggled or corrected by merging and replacing points. This is done to prevent elements failing after meshing.Below is an image of the final cleanedup model.

GENERATING 3D MESH

3D meshing was done in this project in two different ways. 

1. Converting 2D trial mesh to 3D tetrahedral mesh.
2. Volume tetra mesh

Housing component was 3D meshed using this method. This method is done by using trials to mesh the component in 2D. This is done very easily using the automesh tab and setting the element type to trials. Per the task requirement the target element size was set to 5mm with min and max 2mm to 7mm. Since we meshed in 2D it is optimum to control the 2d element size to be within the limit for good mesh quality. After cleaning the elements , the model is remeshed this time using 3d Tetra mesh and setting the tetra remesh parameter to

Min element : 2mm Max : 7mm

Including fill voids, smoothening ,  fixmidnodes 

tet collapse =0.15

Final meshed image below

     Volume tetra mesh

The chassis geometry which consist of 4 components identical on two sides were all meshed using the enclosed volume tetra meshing. Mesh was done using an eclosed surface and target element size of 6mm.All four components was meshed and reflectd across the z-axis.This method is straight forward and quite easier than the first. Below is an image of the final meshed model

Tetmesh Component 

The third geometry was also meshed using the volume tetra mesh method after cleanup. All 3D meshing was done by setting tetrameshing parameter of 

Tet collapse =0.15

Checked smoothening

Checked fill voids 

Checked mixnodes and setting required minimum and maximum lenght.

Results And Conclusion

After the mesh is completed it is required to check that all elements pass the required tet collapse value of 0.15

After meshing of all three models there was a few elements which failed tet collapse. This was fixed by first remeshing the components again . If there are still more failed elements then they are fixed by using the distance option and translating nodes to increase the tet collapse of the elements. Below is an image of some fixed failed elements

Conclusion

The objective of this task was succesfully perfomed and passed all quality test as can be shown below

HOUSING

TETRAMESH

CHASSIS

*COMMENTS* : THE HALF MESHED CHASSIS IS PRESENTED BECAUSE THE APPLICATION ALLOWED ONLY 100000 NODES TO BE SAVED.