• Vincent Faucher, CEA - Commissariat à l'Energie Atomique et aux Energies Alternatives
• Olivier Jamond
• Nicolas Lelong
• Benoît Prabel
• Maria-Adela Puscas

The proposed mini-symposium addresses challenges and locks for fluid-structure interaction in industrial framework. It is designed to stand out from the numerous and interesting topics associated to FSI in the sense that it gathers and tackles subjects with direct link to industrial applications.
This can obviously be related to large-scale simulations implementing complex and detailed systems, for which the challenge is the completeness of the modeling and the efficient use of high-level computational power taking into account the non-linear interactions between the modeled components. Are also of great practical interest the development of reduced and efficient numerical modeling which enable to catch the complexity of the physics for a minimal computational cost.
As examples for such topics, we can introduce full-scale reactor simulations for safety transients in nuclear industry, dynamic response of offshore installations submitted to gravity waves or in flight interactions for airplane wings involving external turbulent air flows and internal sloshing fuel.
However, the mini-symposium is also willing to address topics at more local scales, closer to physics and hard-to-understand phenomena known to be the limiting factor for a wide range of problems in the industry. One significant example of such a situation in fluid-structure interaction is the accurate representation of contact between immersed structures where the flow between and through the structure(s) opens a variety of unsolved problems, from both physical and numerical points of view. Such problems introduce for instance the question of the actual representation of the fluids and structures in interaction and address the sensitive question of immersed boundaries versus exact localization of fluid-structure interfaces coming with mandatory and often very complex ALE mesh motion. Providing knowledge and guidelines to handle modeling issues of this kind is of primary interest for industrial purposes. The same interest applies to the best-informed choice of the relevant modeling of the turbulence in the fluid. It goes from inviscid flows with no turbulence when pressure wave propagation is preponderant in the coupled solution, to advanced Large Eddy Simulation or Direct Numerical Simulation when needed, again depending on the configuration and on the actual effect of the fluid onto the structure. In the search for the optimal solution procedures, intermediate approaches such as Reynolds Averaged Navier-Stokes must not be a priori discarded when they can provide the appropriate effects and allow the representation of more complex structures serving the global purpose of the industrial analysis of interest.
More generally, the latter statements widen the scope of the mini-symposium to the general effects of turbulence and waves on flexible structures, with possibly subtle effects at local scale showing large consequences on the global response of the system of interest. FSI is likely to modify the apparent characteristics of an industrial system (mass, stiffness and damping basically) in a way that it would be very useful to predict starting at local scale (through simulation and/or smart experiments) and not only assess through full scale complex tests compensating for the lack of general knowledge of the involved physics. To this extent, advanced experimental developments, hopefully connected to simulations, are totally in the scope of expected contributions. Finally, the locks for the industrial analyses of interest are also likely to come directly from numerical considerations, and thus the current mini-symposium fully welcomes works dedicated to advanced coupling strategies, especially those designed to handle severe non-linearities, in both structure and fluid, representative of real systems. It addresses innovative coupling schemes and time-stepping strategies achieving both robustness and stability in any situation while preserving the accuracy of the solution to capture the subtle phenomena with potential large consequences mentioned above. It involves as well versatile and efficient software coupling to provide engineers with computational solutions with the most suitable solvers where they are relevant, working together in a high-performance and user-friendly way. Likewise, numerical methods targeting model reduction (like reduced order model, enriched elements or mesh refinement) and the efficient computation of system response in some parameters space (like continuation method based on HBM or collocation discretization) are fully relevant in this mini-symposium as they are of practical interest in the understanding and design of industrial system involving fluid-structure interactions.