Meshing of Door Inner Panel Challenge

2-D Shell meshing of Side Door Inner Panel using Hypermesh

AIM: The aim of this project is to extract a mid surface via the Manual method for the given model and perform 2-D meshing for the given quality criteria.

OBJECTIVES:

1. To import the model into the Hypermesh module and check for geometrical errors and clear them so that we can extract a Mid surface manually.
2. To set the quality criteria and mesh the parts using 2-D Shell mesh.
3. Make sure that the flow of mesh is maintained and avoid rotating quads, pattern trias, and opposite trias.

PROCEDURE:

First, we will have to import the model into the Hypermesh module. We can do that using File`rarr`Import`rarr`Model/Geometry.

Once the model is imported this is how it will look. Also, change the view to wireframe so that we can check the model is fully closed or not. As if the model is not fully closed taking the Automatic mid will be difficult. Since we are gonna extract a Manual surface you can also manage with open surfaces but it is not recommended.

Since this is a complex geometry manual surfacing is the best option so we can start with the Manual mid-surfacing.

From the above image, you can see that there are red lines showing open surfaces but correcting this open surface will take time to correct but we can just use the opposite surface to take the mid and continue with the mid-surfacing without closing the surface.

Using Geometry`rarr`Surface Edit `rarr`Offset. We can select the surfaces we want to offset make sure the vector normal is checked and give the offset value. Also, you will have to create a Duplicate before offsetting. Then all the individual surfaces will be switched together using stitch.

The features like this have been captured with mid surfaces forming a plus sign.

The yellow lines show that three surfaces are connected together and you can see how such surfaces are captures.

From the Red lines in the edges, we can see that a MidSurface has been extracted correctly.

By changing the view to wireframe we can check if the Midsurface is extracted correctly from the parent body and we can see that all the lines are in the middle. We must follow the same procedure for the rest of the parts and make sure you Organise them into Different components with different thicknesses.

Since the Mid-Surface has been extracted we can now start with the meshing. Before meshing we must upload the Quality Criteria.

We will be meshing the whole component using the above criteria.

To get a good flow of mesh it is recommended to cut the part into Square sections and mesh it from each surface. These lines will help in bringing a good flow in the mesh.

While meshing we will encounter many element errors which must be corrected by us using Quality Index`rarr` Element clean up. We must use a combination of Drag trias, Split, Combine and move the node to clear them.

Once the meshing is done we can assign the material and property where we can assign the thickness of the material. Once the thickness is given we can see the shell as solid using the 2-D Detailed element representation. Using this method we can check the feature capture with the parent body.

From the above image, you can see the varying colors are the varying thickness in different components.

While checking for free edges this is how a model with no free edges will look like. Only the edges at the end will be visible. Also, there are a number of ribs so T-Connections in edges also have to be checked.

RESULTS:

For the given Side door model we have extracted the mid surface and meshed it without any errors for the given quality criteria. Here are some images of the given model.