自航時の船尾水面近傍の流場に関する研究

抄録

The structure of flow field near free surface at the stern of ship models is investigated experimentally by means of measurement of velocity distribution and flow visualization. It is found that a strong difference exists in flow structure near free surface at the stern between the self-propulsive ship models with a rudder and without it. The difference is characterized by the occurence of a pair of vortices rotating outwardly in the model with a rudder. The physical explanation for this phenomenon is attempted both experimentally and theoretically. Flow visualization by means of air bubble method is carried out for a propeller-rudder system and an asymmetric distortion of flow field is pointed out due to strong interference between the propeller slip stream and the rudder. The result is explained from the standpoint of vortex filaments dynamics.