Fluctuating Lift Acting on a Square Prism with Attacking Angle Commencing Its Motion in Still Water （Suppression of Nonrepeatability in Fluctuating Lift Produced by Vortex Formation）

摘要

The purpose of this study is to investigate the nonrepeatable characteristics of fluctuating lift in the case of a square prism. Variation of fluctuating lift with towed distance or swing angle were measured for various attacking angles from 0° to 30°. And the effect of attacking angles on fluctuating lift was evaluated by standard deviation of lift data at specific towed distance or swung angle. Moreover flow visualizations were also carried out to study the flow pattern for different attacking angles. The result of this study shows that attacking angle is helpful to reduce the nonrepeatable characteristics of fluctuating lift most effectively in the case of swing motion.