Lagrangian controllability for the 3D Navier-Stokes equations

Description:  In the Eulerian approach, the motion of an incompressible fluid is usually described by the velocity field which is given by the Navier-Stokes system. The velocity field generates a flow in the space of volume-preserving diffeomorphisms. The latter plays a central role in the Lagrangian description of a fluid, since it allows to identify the trajectories of the individual particles. In this talk, I will show that the velocity field of the fluid and the corresponding flow of diffeomorphisms can be simultaneously approximately controlled using a finite-dimensional external force. The proof is based on some methods from the geometric control theory introduced by Agrachev and Sarychev. Date:  2017-09-27 Start Time:   14:00 Speaker:  Vahagn Nersesyan (Univ. Versailles, France) Institution:  University of Versailles, France Place:  Sala 5.5 Research Groups: -Analysis See more:   <Main>