Dynamics Analysis

V. Daru, N. Delprat, Y. Fraigneau, F. Lusseyran, L. Pastur, S. Pellerin, B. Podvin, D. Sciamarella and C. Tenaud



Flows in real situations, whether natural or technique are generally characterized by the variation in time and space of local quantities that describe them, speed, pressure, density, etc. However the interaction of the fluid with the solid around him, or more generally the boundary conditions, reduce the extent of the range of spatial and temporal scales actually present. It is then possible to complete the statistical approach with an analysis of the interaction between these structures.

Therefore, in this theme we favor the physical study of unsteady model flows and the understanding of fundamental dynamic phenomena through the spatiotemporal characterization of coherent structures. The tools used and developed, range from high-performance numerical simulation, to original experiences, through the development of advanced analytical methods, such as, modal decomposition, identification of Lagrangian coherent structures, tools of analysis of nonlinear dynamical systems.

These methodological developments are based on the study of academic or applied flow patterns, as flow inside an open cavity, flow around a thick plate, pulsating jets (unsteadiness of the glottal jet), interaction between two facing open cavities, etc

Spanwise flow structures inside an open cavity: space(x,y)-time diagram of vorticity Iso-surfaces computed from the experimental velocity field measured by time resolved 2D PIV.