Experimental Verification of Drag Forces on Spherical Objects Entering Water

Experimental Verification of Drag Forces on Spherical Objects Entering Water

Objects which pass from gas regions to liquid regions experience elevated impact forces associated with the acceleration of the surrounding liquid. In order to investigate these forces, complementary experiments and simulations were performed on a sphere that traveled from air to water with an impact velocity of 2 m/s. It was found that the two methods gave results that were in very good agreement. In particular, the depth vs. time trajectory of the sphere closely matched. A fitted polynomial allowed the entry region acceleration to be extracted.