Tutorial: Creating a sphere dimer with SALOME

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This tutorial is aimed at familiarizing you further with SALOME, in order to create more complex shapes (multiple bodies, multiple materials, etc.). You will create a sphere dimer, where each sphere is a different material.

You will learn:

  • How to create complex shapes (multiple bodies)
  • How to assigning different materials to each object

The following assumes that you thoroughly understand the basic concepts in the tutorial Creating a sphere with SALOME.

Tutorial

Starting SALOME

The first step is to (obviously) start SALOME.

Creating the geometry

Then, start the Geometry module. Create two spheres, each with a radius of 10, using the Primitives toolbar.

Next, click Sphere_2 in the Object Browser, and click the Translation button (circled in red, in the following image) on the Transformation toolbar (also circled in red). This will make the Translation Of An Object dialogue appear, as shown in the following image. Change Dz to 30. Click Apply and Close.

SALOME translation marked-up.png

We now need to combine these two spheres into one object. Ensure that both Sphere_1 and Translation_1 are selected in the Object Browser. Then, go to Operations $\rightarrow$ Partition. See the following image.

SALOME partition.png

This will make the Partition Of Object With Tool dialog pop up, as shown in the following image. Click Apply and Close.

SALOME partition dialogue.png

Create the volume groups

Now, the volume groups for the partition must be set. Since there are two objects this time, and we wish to set different material properties for each, the following must be done twice.

Ensure that Partition_1 is selected in the Object Browser, then create a new group using New Entity $\rightarrow$ Group $\rightarrow$ Create Group. Select the volume button Shape Type. Then, click Select All. This will select both objects. See the following image.

SALOME dimer create group 1.png

Select the second object, labeled 11. Click Remove. This should leave only sub-shape 2. See the following image.

CHANGE THIS IMAGE

SALOME dimer create group 2.png

Click Apply (not Apply and Close).

Then, click Select All again, and remove sub-shape 2. Click Apply and Close.

Note that, at this stage, the two groups created above should appear in the Object Browser. See the following image.

SALOME dimer geometry groups.png

Create the mesh

Now the mesh can be created. Be sure that Partition_1 is selected in the Object Browser and switch to the Mesh module.

Then, create the mesh, by going to Mesh $\rightarrow$ Create Mesh. Click on Assign a set of hypothesis and choose 3D: Automatic Tetrahedralization from the drop-down menu. The Hypothesis Construction should appear. Accept the default values by clicking on OK. Click Apply and Close on the Create mesh dialogue.

Now, compute the mesh. Ensure that Mesh_1 is selected in the Object Browser and go to Mesh $\rightarrow$ Compute. The Mesh computation succeed dialogue should appear. Click Close.

Create the mesh groups

Ensure that Mesh_1 is selected in the Object Browser. Create a group by going to Mesh $\rightarrow$ Create Group. Select Volume as the Elements Type. Change the Name to 1. Click on the Group on geometry button. Then, click the arrow next to Geometrical Object and select Direct geometry selection from the drop-down menu. Next, click Group_1 under Partition_1 in the Object Browser. This should populate the Geometrical Object field in the Create Group dialogue. Click Apply.

Then, the second group needs to be set. Change the Name to 2. Then, click Group_2 under Partition_1 in the Object Browser. This should populate the Geometrical Object field in the Create Group dialogue. Click Apply and Close.

Export the mesh

The final step is to export the mesh. First though, check that the Object Browser matches the following image:

SALOME dimer object browser.png

Assuming that things look correct, click on Mesh_1 in the Object Browser. Finally, go to File $\rightarrow$ Export $\rightarrow$ UNV file. Save the file in your work directory.