The effect of slenderness ratio on water entry

In the paper, air cavity created by vertical water entry of cylinders with different slenderness ratio (defined as “s=L/D”) is investigated experimentally, theoretically, and computationally. The study focused on range Froude numbers, Fr = V /( gr ) 0.5, (12< Fr< 30). Particular attention given to effect ratios surface seal time, evolution process cavities. To understand physical processes, we conduct several experiments length cylinders. A theory model considering added mass (induced motion), buoyancy force, gravity, water-resisting force developed predict relationship between falling distance time. Studies show that for same size bullet time decreases increase impact speed. Under identical speed, ratio. For consistent value “s” increase, (the moment). captured theoretical match experimental numerical data.