Flowing matter lies at the crossroads between industrial processes, fundamental physics, engineering and Earth Sciences. Problems are often too complex to be attacked from first principle or by brute force numerical methods. We need to model to reduce the number of degrees of freedom and/or we need to control to drive the system toward a less unpredictable behaviour. We are considering multi-scale interactions among a fluid matrix and dispersed structures as for the case of an assembly of molecules, mesoscopic particles, active biological and artificial entities, solid macroscopic objects or turbulent `coherent' fluctuations. We often understand the microscopic or individual behaviour but we lack a way to systematically upscale the problem to continuum descriptions. Flowing matter frequently presents a tight coupling between multi-scale structures and large-scale flow urging for a unifying view at both Lagrangian and Eulerian levels.
Can we control complex flows by suitable Eulerian/Lagrangian optimal feedback? How to downsize the complexity and develop accurate sub-grid or multi-scale models? Can one learn how to escape from strong turbulent fluctuations? Or how to harvest fluid energy in a efficient way? What about robustness and universality of hydrodynamical models for active matter?

Aim of the workshop is to focus on modelling, going beyond brute force numerical approaches. We are interested to foster synergies among the communities working on modeling active matter by continuum Eulerian approaches, tailoring active particles to achieve optimal goals, understanding how biological entities learn and evolve in complex environments, modelling/controlling turbulence or complex flows in order to optimise applied problems or to develop fundamental understanding of multiscale dynamics, applying machine learning or modern data assimilation techniques to cope with big-data and/or complex behaviour in a high dimensional phase space.

FSIM-2017 is meant to coordinate the research activities of the scientists belonging to the COST Action "Flowing Matter" MP1305 and in synergy with the scientific program of the ERC grant NewTURB "New eddy-simulation concepts and methodologies for frontier problems in TURBulence".

A special issue of European Physical Journal E Soft Matter and Biological Physics on "Fluid Structure interactions and modeling in complex flows" is planned with contributions from the participants to the workshop.