Moving a bead in a viscoelastic medium 3D

General Discussion
1

I would like to model a (spherical) bead in a (spherical) 3D visco-elastic medium.
The bead is first moved around actively by external forces.
Once these forces stop, I want to find out the movement of the bead due to the visco-elastic relaxation.

Would that be possible to model in FreeFem ? Any pointer one where I should look to get started ?

Thanks !

1 Like
2

Yes I think is possible, but first you need the mechanical model . If you do this in the framework of the bead, the domain are fixe or you have just small deformation. It will be not to hard to do.

2 Likes
3

Thanks for the reply !

So to be clear, the bead is moving inside a sphere of visco-elastic medium. The bead and its displacements are rather large compared to the sphere size so I don think I can work in the framework of the bead.

I guess I need a model for the bead, and I think a stiff linear elastic will do. I do not care about the bead deformation, and in the analytical formulation, the bead is mostly a moving boundary condition - albeit moved around by the visco-elastic medium.

Orders of magnitudes : bead radius is 1/4 of sphere radius ; bead displacement is also 1/4th of sphere radius.

4

Sorry, for me it very hard to understand what is you problem without graphic.
Please a small hand plot will really help me.

5

Sorry if I was not clear ! Here is a schematic :

illus
illus1354×787 77.7 KB

6

So this is just a large non linear elastic problem, so problem for except the
modele of the viscoelastic medium.