AIM: MID SURFACE EXTRACTION OF BOTTLE CAP AND MESHING BY PREPROCESSING SOFTWARE ANSA

The meshing of this model is divided into 3 parts.

1. Geometry cleanup
2. Midsurface extraction
3. Meshing

• Import the model of the bottle cap in ANSA

• Assign a target length of 5 ( as per mesh quality criteria). assign a PID for reference purposes.

• The first step will be geometry cleanup, running the geometry checkup and fixing the errors.

• MID SURFACE EXTRACTION
• The next step is mid surface extraction of the bottle cap model.
• when to do mid surface extraction?
• when two dimensions are very large in comparison to 3rd dimensions or (sheet metal modeling or surface modeling (thickness less than 6 mm)the easiest way to do is mid surface extraction. manual and auto both methods are used which is directly dependent on model and level of accuracy.
• Use a multi and offset option as per geometry. Midsurface of the final model will look like below.

• MESHING

• The next step will be meshing as per the given quality criteria.

1	Target/Average length	1
2	Minimum Length	0.5
3	Maximum Length	3
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

• Use the different algorithm to do mesh , & edit it by reconstruction , split , cut , release & paste options.
• The final mesh will look like the below image.

• Assign a relevant PID as per thickness and check the draw shell as solid from options.

Learning outcomes

• Mid surface extraction by offset and the multi middle option
• Importance of 2d meshing.
• Assigning thickness after meshing with the use of relevant PIDS.
• Elimination of all errors under given quality critriea.

Google drive link for model :

https://drive.google.com/open?id=1kLeCrz3GMoWe8wvdm90X0ouKKAkP4D35