Person in charge: Jean-Philippe Laval
The scientific projects of the team are focused on the characterization, analysis and modeling of turbulent flows, and on flows with rotation. All scales of turbulence are of interest, whether in wall turbulence to study modeling and control, or in rotating flow where the transient effects of rotation, instability and phase change of the fluid are taken into account.
The first research area concerns wall turbulence where the primary focus is on boundary layers with and without pressure gradient. Two different and complementary approaches are employed: the quantitative statistical analysis of coherent structures and numerical modeling. This work relies heavily on experiments using many hot wires (more than 100 at a time), optical metrology (especially PIV and SPIV) and direct numerical simulations (DNS). A major emphasis is on post-processing of data, which is performed using modern mathematical tools to extract relevant data from both experiments and that generated numerically. Numerical modeling using the LES approach is also carried out, and is of particular interest for flow control in wall-bounded flows, especially for the suppression of separation. A particular interest of the group is in the design, characterization, and modeling of actuators for detached and unstable wall-bounded flows. In support of this, detailed studies of control of separation are carried out both experimentally and numerically, including the study of closed loop control.
The second major research theme is rotating flows with two main application areas: turbomachinery and geophysical flows. For the former, the objective is the development of relevant numerical simulations based on experimental databases, which are reliable and detailed only for single-phase flows in cavities. The unsteady aspects, the coupling phenomena, and their interactions are obviously of primary importance and require the development of sophisticated metrology. Modeling is currently performed using a RANS approach, but this is being extended to include DES (Detached Eddy Simulation) that better takes into account the influence of large coherent structures. For geophysical flows, the competence of the team in the Hamiltonian approach is being applied to various problems of vortex flows at the scale of a planet or of the universe.
Créé le : 10-11-2004 17:40