Trailing vortex detection and quantitative evaluation of vortex characteristics by PIV technique

This paper summarises the activities performed in order to investigate the formation, motion and persistence of trailing vortices released by large commercial aircraft. Two different experimental test campaigns were carried out in two different large towing tank facilities performing PIV measurements. The lesson learned by the first investigation and by the experience of the scientific community, the solution adopted in order to characterise the wake vortex by the initial formation phase down to wake collapsing in the far-wake region are illustrated. Together with the adopted technical solution, with the selected experimental facility and with the improved measurement system, a particular care is taken: on the data analysis description, on the importance of advanced PIV algorithms and on the selected postprocessing methods for evaluating the main magnitudes characterising the vortex structures.