Week 12:Project-1-Meshing of Door Inner Panel Challenge

Aim:

1) To mesh the given automobile side door interior plastic component in hypermesh with the quality criteria given below.

S.No	Quality Criteria	Value
1	Aspect Ratio	5
2	Skewness	45
3	Warping	15
4	Taper	0.5
5	Min. Length	2mm
6	Max. Length	6mm
7	Min angle Quad	45
8	Max angle Quad	135
9	Min angle Tria	20
10	Max angle Tria	120
11	Tria %	10
12	Target Element Length	4mm

2) To assign thickness to the mid-surfaced and meshed components.

Theory:

The model given to us is the Automobile Side Door Interior Plastic Component. These plastic are manufactured using the injection molding process in which the plastic in the molten form is injected into the mold or die to get the desired shape of the component. The material used in these interior parts is polypropylene which is high strength plastic material and it also has the ability to absorb heavy loads in the event of a crash or an impact on the body.

Procedure:

• We first import the model into the hypermesh using the import model option.

• We see that the model is a plastic interior door trim model with complex geometry having clip-on, ribs, and dog houses as shown in the image.
• Geometry clean-up is done on one side of the part by removing free edges and collapsed surfaces inside the surface and this error-free surface is to be offset to generate the mid surface.
• The thickness of the base part is measured using the Distance option under the Geometry module and extract mid surface only for it using the offset option under the Surface edit panel of the Geometry module.
• Then we extract the mid surface for all the ribs, cylindrical component, and mounting clips using the midline creation, and by using the free lines, a new surface is created.
• Then segregate the surfaces having different thicknesses into appropriate collectors by mentioning their thickness value.
• After extracting the mid-surface for all the ribs, cylindrical component, and mounting clips we need to extend them to the base surface so, that the connectivity is maintained throughout the mid-surfaced component while meshing the component. For that, use the extend command under the Surface edit panel of the Geometry module. We input the extension distance and the surface onto which we have to extend the components and then, we press on to extend. All the ribs, cylindrical component, and mounting clips are extended to the base as shown in the image given below.

• Then meshing is performed on the component after defining the quality criteria as mentioned in the objective.
• Then meshing is performed on the model component by component. We first mesh the base surface using the Automesh option under the 2D module. We first enter the target element length as 4mm with the type of mesh as mixed and then select the surface to mesh and finally, click on mesh. 
• Then mesh all the ribs and cylindrical surface and then, we go to the quality index option under the 2D module to clear all the quality issues that we are facing in the model. We use all the QI cleanup tools to get rid of all the quality issues. Then, we can also use the Rebuild mesh, Smooth, and elem cleanup options in the 2D module so that, we can obtain better mesh with lesser tria concentration.
• By using the above-mentioned techniques proper flow of mesh is achieved as shown below.

• Then property card is created for each component having different thickness and define their thickness value in the card.

• Then assign the property card to each collector.
• Finally, we assign thickness to all the components using the 2D element representation as a detailed representation in the visualization tab as shown in the image given below.

Conclusion:

1) We have done the geometry cleanup.

2) We have taken the mid-surface for all the components using the manual-offset option.

3) We have also meshed the mid-surfaced components one by one and then, cleared all the quality issues using QI cleanup tools, Rebuild mesh, Smooth and elem cleanup options.

4) We have finally, assigned thickness to the model by creating properties for each component. The thickness assignment was done using the 2D detailed element representation option.