Numerical simulation of problems involving the interaction between a very flexible solid and a fluid flow characterized by the presence of waves, drops and splashing.

Marco Lucio Cerquaglia will publicly defend his doctoral thesis entitled "Development of a fully-partitioned PFEM-FEM approach for fluid-structure interaction problems characterized by free surfaces, large solid deformations, and strong added-mass effects"

Fluid-Structure Interaction (FSI) phenomena are encountered in many engineering applications, ranging from the biomedical to the aerospace engineering, and there is nowadays an increasing need for powerful numerical tools capable to efficiently model them. In this work we address some critical features of the numerical simulation of such problems.

  In particular, the presence of free surfaces and of large solid displacements inside the fluid flow represents a major difficulty for traditional numerical approaches, often based on an Eulerian description of the fluid motion. The use of a Lagrangian approach for both the fluid and the solid parts allows to take these aspects into account in a natural way. However, in order to cope with mesh distortion issues typical of mesh-based Lagrangian approaches, a fairly recent meshless particle method, called Particle Finite Element Method (PFEM), has been implemented in a brand-new code and employed in this work to model the fluid.

  The fluid and the solid solutions are then coupled through a fully partitioned approach, which allows to exploit all the features of the coupled solvers at their best.

In particular, in this thesis the nonlinear Finite Element code Metafor, developed by the MN2L lab of the University of Liège, is used to model the solid part. Thanks to the use of a fully partitioned approach, all the nonlinear capabilities of Metafor, as for instance the contact management and the use of complex constitutive behaviors, are readily available. The coupling is made through CUPyDO, an integrated Python environment for FSI coupling developed during this PhD.

Finally, the techniques developed during this PhD have been applied to the simulation of bird strike events on aeronautical structures.

Promotor : Jean-Philippe Ponthot

Practical information

The defence (in english) is open to all and will take place on Wednesday, May 20, 2019 at 15:00 pm, in "Amphithéâtre 01" of the Mathematics Institute, Building B37, at Sart Tilman (access)