The water entry of a solid object has been an important issue in multiphase flows while drawing wide interests of scientists and engineers. It is largely relevant to many different areas such as ship slamming, air to sea weapons, entrance of planes or satellites into a body of water, and any industrial coating process that involves the dipping of a solid object in a liquid bath. While the surface roughness is considered as an important issue in water entry, most previous studies have focused on the effect of static contact angle. Thus, our lab investigates experimentally how the surface roughness affects the water entry of a sphere.
1. Water entry of spheres
The water entry phenomena of smooth spheres (non-cavity-forming case).
The water entry phenomena of roughened spheres (cavity-forming case).
The cavity and splash outlines of roughened spheres. (The black line has rougher surfaces.)