Elastic filamentous structures found on swimming and flying organisms are versatile in function, rendering their precise contribution to locomotion difficult to assess. We show in this Letter that a single passive filament hinged on the rear of a bluff body placed in a stream can generate a net lift force without increasing the mean drag force on the body. This is a consequence of spontaneous s...

For micro air vehicles (MAV), the precise prediction of aerodynamic force plays an important role. The a comparative low Reynold number (Re) vehicle tends to be affected by different flow modes. In this paper, performance three-dimensional NACA0012 airfoil is studied numerically. A range angles attack ( α) 0°−25° and Reynolds 1000 considered. Mean fluctuating coefficients forces around are anal...

By performing three-dimensional magnetohydrodynamic simulations including Alfvén eigenmode perturbations most unstable to the ionospheric feedback effects, we examined the auroral vortex street that often appears just before substorm onset. We found that an initially placed arc splits, intensifies, and rapidly deforms into a vortex street. We also found that there is a critical convection elect...

Julien Christophe, Stéphane Moreau, Jérome Anthoine 1 von Karman Institute for Fluid Dynamics, 72 Chaussée de Waterloo, 1640 Rhode-St-Genèse, Belgium, [email protected] 2 Université de Sherbrooke, 2500 Boulevard de l’Université, Sherbrooke, J1K 2R1 Québec, Canada, [email protected] 3 ONERA The French Aerospace Lab, Midi-Pyrenees Center, Mauzac, France, Jerome.Anthoine@one...