The work reported here comes within a broader research program dealing with ambianceudseparation or confining by means of air curtains (plane air jets). The process is studiedudexperimentally by Particle Image Velocimetry (PIV). In this paper, the emphasis is put on theudflow structure in the impingement region of such jet systems insofar as it is where transfersudoccur preferentially. More precisely, a vortex eduction method was implemented under theudMatlab environment enabling both the automatic detection of 2D coherent patterns embeddedudin PIV velocity vector maps, and a statistical analysis of the topological and energy featuresudof these structures. First, the approach is explained in detail. The second part of this paper isuddevoted to its application in the case of plane turbulent impinging simple- and twin-jets forudvarious jet exit velocities. Results about the size, the shape, the spatial distribution and theudenergy content of the detected vortices are provided. Although many questions still remainudopen, new insights into the fashion these structures might form, organize and evolve areudgiven providing an original picture of the plane turbulent impinging jet.
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