Bruno Levy, researcher and director of INRIA Nancy Grand-Est is invited for a LIRIS seminar around fluid simulation and optimal transport, on Monday, February 24th, in Nautibus, room C5. Abstract: I will talk about some numerical methods to simulate incompressible fluids with free boundaries. The methods I'm interested in [Gallouet & Merigot, DeGoes et. al] decompose the fluid into a set of cells (power diagram) in such a way that the volume of each cell remains constant, hence enforcing incompressibility. The volume constraints uniquely determines the parameters of the power diagram, that can be found by maximizing a concave objective function (semi-discrete optimal transport). I will show some examples of 3D fluid simulations with free boundaries, viscosity and surface tension, as well as applications in astrophysics.