EXPERIMENTAL-ANALYSIS OF VORTEX FLOW DEVELOPMENT

The development of a vortex structure in the presence of an opposing pressure gradient that does not cause it to burst was analyzed using a wingtip eddy type device. The resulting vortex flow was investigated in great detail both by laser tomoscopy visualization and by 3D laser velocimeter measurements. The tests were conducted in the Fauga-Mauzac F2 return flow wind tunnel with a test section approximately five meters long and an inflow velocity of 25 m/s. The vortex field at a large number of stations was thoroughly analyzed to define its mean and turbulent properties. The mean internal vortex structure exhibited an overvelocity in the center, decreasing in the streamwise direction. The external velocity field is correctly represented by a potential vortex. The presence of general lateral motions in the flow causes low frequency oscillations which are superimposed on the turbulence.