Abstract
Water model experiments are described in which spheres of various diameters and specific gravities were dropped from typical industrial heights into water. Maximum penetration distances, trajectories and retention times were measured and compared with theoretical predictions based on transient fluid flow. The relative importance of steady drag, added mass and history forces were demonstrated. Results indicate that immersion times are extremely short ( similar 1 second) for aluminum additions and low density ferro-alloys. High density ferro-alloys remain immersed considerably longer and penetrate much deeper.