Week 4 - 2D Meshing for Sheet Metal

AIM:

For the given CCB CAD model, Check the Geometry cleanup, do the mid surface, and to Mesh it with the below 2D element Quality criteria.

GIVEN DATA:

Steps involved in the procedure:

1. To check all the geometry error and to fix them.
2. Mid surface to be made for all the geometrys.
3. To generate mesh with good flow in the given quality criteria.

PROCEDURE:

• Open the Ansa work bench ANSA v19.1.4.
• Import the given hood model from the downloads
• In ANSA we can import all the CAD Software file formats like IGES,STEP,etc.
• And we have to define the material and to orient the components.
• The model consists of 5 components listed below.

Given model:

The given cad model consists od 34 components

STEP 1:

• We have to fix the geometrical errors in the parent component,Then only we will be able to do midsurface using skin and offset.
• Tool Bar >> Checks >> Geometry.

• After clicking on the check geometry and executing it,The geometric errors will be displayed.
  
  

• We can fix that geometric errors by manually or automatically by using the auto fix option.

• after fixing the errors, we have to run another check then it will show no errors .

• similarly we have to do the same procedure for all the components.

STEP 2:

• Before doing mid surface we have give the length for every component to mesh properly.
• Mesh Module >> Perimeters >> Length.

• Then the length of the perimeters and macros should be given 5.

• the same procedure is followed for every components.
• After giving the length mid sufacing is done

STEP 3:

MID SURFACING:

• mid suface can be done by 2 methods by automatic method and manual method.
• auto method Topo Module >> Faces >> Mid Surface >> Skin >> Select the Face.
• manual method Topo Module >> Faces >> Offset .
• Here we have used auto method as well as manual method .
• the below image is the mid surface of the total 34 component.
• each component mid surface is given in the below ansa file.

STEP 4

• Before meshing the given data is added to the quality criteria of the components

• And in presentation parameters element percentage and all details are turned on for better visibility.

STEP 5

MESHING:

• To apply mesh use << BEST MESH < MESH GENERATION>> and to remove the mesh use<< ERASE < MESH GENERATION >>.
• To increase the quality of the mesh use <>RECONSTRUCT,<>SMOOTH options.
• To increase the qual;ity manually <> SPLIT /SWAP / JOIN
• the below images are the meshed images of the main assembly component, all components file is shared.
• tria percentage is achieved at 5.11%.

LEARNING OUTCOMES:

• I can now able to generate geometry clean up and property Ids
• can do mid surface for any component
• understood how to do mesh for complex geometry

CONCLUSION:

Thus for the given CCB CAD model, the mid surface for all the 34 components are generated and the geometrical errors are identified and fixed and meshing of the components with the given element Quality criteria is done.