Which data mapping method should I use for large deformations?

Nikrouz asked on the mailing list (Sep 13, 2019):

I am going to use OpenFoam-CalculiX for FSI simulations.
At this time, I am have technical question for preparing preCICE config file. The case I am going to run has very large deformations. Fortunately, CalculiX solver can handle the large deformations. On the other hand, large deformations necessitate using efficient mesh correction algorithms(Dynamic Mesh in OpenFoam).
Considering this point, can anyone suggest the best coupling method available in preCICE? Currently, I am using parallel RBFmapping.

The mapping problem that preCICE solves should be independent of the amount of deformation. The coupling interface on OpenFOAM side runs completely in the Lagrangian mode of the ALE framework. So does CalculiX. This means you compute the mapping between both meshes always in their reference domain. For RBF, this means that the system matrix always stays the same – you compute the same mapping in every timestep, just with different values.

General remarks on how to tune your RBF mapping, you can find in the wiki. We also wrote a paper on the RBF mapping in preCICE a while ago.

Of course, like you mentioned, the mesh deformation algorithm in OpenFOAM is a completely different story. Here, you need a powerful solution for large displacements.

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