Characterization of the Near-Wake of an Ahmed Body Profile

In aerovehicles context, the flow around an Ahmed
body profile is simulated using the velocity-vorticity formulation of
the Navier-Stokes equations, associated to a penalization method for
solids and Large Eddy Simulation for turbulence. The study focuses
both on the ground influence on the flow and on the dissymetry of
the wake, observed for a ground clearance greater than 10% of the
body height H. Unsteady and mean flows are presented and analyzed.
POD study completes the analysis and gives information on the most
energetic structures of the flow.

Authors:

• Stéphanie Pellerin
• Bérengére Podvin
• Luc Pastur

Keywords:

• Ahmed body
• bi-stability
• LES
• near wake.

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