Theoretical and Experimental Velocities of Free-Falling Spheres in a Stratified Atmosphere.

摘要

An important factor in the sound produced by an object impacting the water surface is the impact velocity of the object. A series of tests was conducted at the Atlantic Undersea Test and Evaluation Center (AUTEC) to determine the free-fall impact velocity of various size and weight spheres. The experimental data were then compared with the predictions of a mathematical model,which calculated impact velocities based on the drag coefficient,Reynolds number,drop altitude,and physical characteristics of the sphere and the atmosphere. After some modifications were made to the drag coefficient-versus-Reynolds number curve,good correlation was obtained between the experimental and calculated impact velocities.