Experimental investigations on the integrated bubbly wake strength of two different scale ship models

ABSTRACT The integrated bubbly wake strength of two ship models with different scales is investigated in this paper. The laser spot video recording technique is implemented to measure the light scattering properties of laser beams transmitted through the wake. The bubbly wake is generated by the movement of two geometrically similar models towed at constant velocities in a towing tank. The effect of the model’s velocity and scale are investigated using data provided by the multiple laser emitter and detectors. Results show the dominance of small bubbles on the persistence of the wake. Also, the effects of wetness of the stern on the vertical distribution of the wake are evident. Comparing the wake of two scale models shows a stronger wake for the bigger model in similar conditions. Moreover, the importance of Froude and Weber numbers on the scaling of major features of the bubbly wake of ship models is prominent.

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