Preprocessing for structural analysis of a sheet metal Rear Wheel holder

Mesh the Rear Wheel Holder with the given Quality Criteria and assign the thickness

Introduction

Rear Wheel Holder

The rear-wheel holder is the part that is mostly situated in the trunk or boot space of the vehicle and is used to keep the extra wheel in case of any emergency or failure. The material used for the rear wheel holder is sheet metal.

So in this project, we are going to extract the mid-surface from the model and we are going to mesh that.

We do the meshing so that we can do the many types of testing. On the basis of those test results we are going to assign the property and metal to the model and we can make some changes to the model according to that.

Procedure

1. First we are going to import the model.

2. We are going to give the criteria file setting.

3. The thickness of the components is less than 6 mm. So when the thickness of the component is less than 6 mm we can extract the mid surface and we can mesh on that. It is easy to do the 2-D meshing as compare to the 3-D mesh. That is why we convert the 3-D model into the 2-D model and after meshing we give the thickness to the elements.

4. Now we are going to check if the components have a uniform thickness or not. For auto mid-surface extraction, the thickness of the model should be uniform.

5. So we found out that the thickness is almost uniform. Apart from the one region, the thickness of the model is uniform. So we are going to extract the auto mid-surface and in the end, we can assign the thickness properly.

6. After mid-surface extraction we are going to do the geometry cleanup. We check the areas where if we mesh it fails for the quality criteria and according to that we are going to do the changes in the geometry.

7. Now we are going to delete---------------------. Because it is going to fail if we mesh in that region. beads

So we are going to delete those surfaces and we are going to fill that gap with a flat surface. For that, we will go to the quick edit panel and we are going to fill that surface with the filler surf option.

8. Now we are going to repeat the same procedure with the-------------. pin holes

9. Now we are going to delete the surface of---------. Because the surface of the ---------- is default.

Now we are going to position the surface of the----------- to get the proper surface. So we can do the mesh properly in that area.

10. After the geometry clean-up, we are going to start the meshing.

For meshing, we have to go 2D--> automesh

So we are going to do the meshing with the mixed type elements. So that we will not get the rotating quads.

11. During meshing removed the trias which are in opposite direction.

After removing those

Some trias were touching each-other

After separate them

Some trias were in the fillet.

So I remove those

Some trias were touching the feature line

So I did drag those trias

12. When we are doing meshing, we have to keep that in mind that feature capturing should be proper.

13. We have to make sure that the mesh flow is good. The elements should be in a proper way of order structure.

14. Now we are going to assign the element thickness.

There is a region where the thickness is 1.00 mm other than that area the thickness is 0.75 mm. So we are going to create two properties and we are going to assign them separately.

(i) 0.75 mm thickness

(ii) 1.00 mm thickness

15. After the meshing is done we are going to do the element checks. In which we are going to check the free edges, normal of the elements, duplicates etc.

Duplicate Check:-

To check the Duplicate elements we go to Tool--> check elems (F10)

Free edge check:-

To check the free edges we go to Tool--> edges (Shift+F3)

Quality Check:-

To check the quality of the elements we will go to 2D--> qualityindex

Normals:-

To check the normals of the elements we will go to Tool--> normals

16. Now we are going to check that we have successfully assigned the properties to the elements properly.

For that, we will go to menu bar--> Tools--> component table

17. Now we are going to check if there is unnecessary component is present (empty component).

For that, we will go to menu bar--> Tools--> empty

18. Now we are going to check if there is unnecessary property is present (unused property).

For that, we will go to menu bar--> Tools--> unused

19. So we have resolved all the errors from the model and we have meshed the model without any element fail.

tria% = 1.7%

Things to keep in mind while meshing

1. Feature capturing should be proper in the mesh.

2. Mesh Flow should be good.

3. Element should not be failing for any quality criteria.

4. There should be connectivity properly in the elements.

5. There should not be any free edges between the elements.

6. Normals should be in the same direction on the surfaces.

7. Make sure that there should not be no duplicate elements.

Learning Outcome

1. Learn how to do the mesh.

2. Learn the rules which we have to follow while we are meshing the component.

3. Learn how to do the element check.

4. Learn about the different quality criteria.

5. Learn how to assign the thickness to any part of the model.