2. Modeling A

2.1. Geometry and meshing

The geometry in FIG. 1.1-1 is represented by two substructures. A substructure representing the central part, and a substructure representing one of the branches of the star. The central portion is meshed using 45 triangular elements, and the arm is meshed using 104 quadrangular elements. The meshes are compatible at the level of the interfaces between the center and each of the arms.

2.2. Material properties

For modeling A, Rayleigh damping is not considered. We pose \(\alpha =\beta =0.\)

2.3. Tested sizes and results

In this test, for the first three specific modes of the assembly, the relative displacement of nodes located opposite each other, one belonging to the central substructure, the other belonging to the arm, is compared. The three nodes for which the tests are carried out are represented by green dots in Figure 1.1-1. This relative displacement must be zero for each node.