Week 4 - 2D Meshing for Sheet Metal

Objective:

Checking for the Geometry cleanup (if required), taking the mid surface, and Meshing with the given 2D element Quality criteria ,for the given CCB CAD model.

Quality criteria:

S.No	Quality Criteria	Value
1	Target/Average length	5
2	Minimum Length	3
3	Maximum Length	7
4	Aspect	3
5	Warpage	15
6	Skewness	45
7	Jacobian	0.7
8	Minimum Quad Angle	45
9	Maximum Quad Angle	135
10	Minimum Tria Angle	30
11	Maximum Tria Angle	120
10	Tria Percentage	15

Following the below steps :

1. Taking the geometry for portal.

Download the geometry from the portal and open it in the ANSA software . It looks like ,

2. Do Topo on the following model :

To connect the geometry together do Topo.

3.Geometry cleanup:

Do Geometry check to see any errors are present in geometry or not .If errors are there Fix the errors .

Here we got the errors after Executing ,

We fixed the errors and got the clean geaometry.

4.Midsurfacing :

Take one by one part from parent geometry & do midsurfacing of each part seperately.

First measure the Thickness of parent geometry. Here we got the thickness 1.6 ,

So, we selected Offset from Faces option,used Feature angle and selected the upperface of geometry .Then after clicking middle mouse button we get the arrow and pop up to give the offset distance .As direction of arrow is away from the geometry use -sign to offset (-0.8),as shown in following img.

After clicking middle click we get the option to delet the original faces or not,so click on 'No'.

Create seperate property card for midsurface.

Follow the same procedure for all the parts ,we get the Midsurfaced geometry .

5. Meshing

Take one by one part from midsurface geometry & do meshing of each part seperately.

Switch to Mesh Module ,choose Classic Mesh option .

Use length option from Perimeter ,on middle click pop up box opens put 1 there.

Set Mesh Parameters as per given requriments.

Se Quality Criteria as per given requriments.

Select only given parameters & put the values as per requirement.

Use length option from Perimeter ,on middle click pop up box opens put 5 there as target length given is 5'.

Select the part & use Best option from Mesh Generation to generate mesh ,

After meshing we don't get the proper mesh as per quality criteria, so use Reconstruct option from shell mesh .

After Reconstruct,

Try to reduce trias using Reconstruct,Split, Smooth,Collpase options from Shell Mesh .

We reduce Trias and the final mesh we got,

Smillarly we do meshing for all the components .

Final Mesh model: