LAUSR

Using a hexapod ship motion emulator, the influence of floating vessel motion on the trajectory and velocity profile of single ellipsoidal bubbles is investigated from the images provided by a high-speed camera. Varying the amplitude and frequency of the vessel motion, relations between the column motion and variations in the bubbles’ trajectories are analyzed. Spectral analysis by means of fast Fourier transforms helps demarcate the factors influencing the bubbles’ zigzag flow patterns, in terms of contributions stemming from column wall effects, column oscillation frequency, and column angle of inclination. Although the column rolling motion is shown to have little effect on the rising velocity of the bubbles, its incidence on shaping the bubbles’ number density distribution and bubble flow patterns is remarkable, suggesting that these factors have to be accounted for in the marine context of floating vessels.