LAGRANGIAN VELOCITY PROFILES IN THE WAKE OF A HIGH-SPEED VESSEL

A video imaging technique is employed in a towing basin to obtain high resolution surface Lagrangian velocity observations in the centerline wake region of a high speed, twin screw surface vessel. Approximately 30,000 surface velocity realizations within the wake region extending from the stern to approximately six model ship lengths aft are used f or comparison with both recent full-scale and numerical model results. Analysis of this data set reveals spatial decay rates in the mean and fluctuating velocity components which serve to identify relevant scal es of motion and define candidate mechanisms for the persistence of th ese wakes in remotely sensed ocean surface data.