EXPERIMENTAL STUDY ON DRIFT SPEED AND DRAG FORCE OF FLOATING LOG

Abstract

 In this study, we conducted flume experiments to reveal the change of floating log motions in wind blowing. First, we measured the drifting velocity of model logs by changing the model log diameter, specific gravity, and wind speed, and we examined the effect of wind drag forces on drifting velocity of logs. Secondly, we measured the drag forces acting on floating logs and evaluated the drag coefficient of wind drag forces. Results show that drifting velocity of the smaller diameter log increases significantly due to wind drag force, and for large specific density case the drifting velocity doesn’t increase. In addition, drag force measurements suggest that acceleration effect by wind drag forces is larger for smaller diameter log case, and conversely it is smaller for large specific gravity.