Energy losses in non-classical free surface flows

Abstract

One of the most familiar phenomena associated with the motion of water is the breaking of waves at the seashore. Another important, albeit less familiar example, is the impact of a liquid jet, formed during the collapse of an underwater bubble. Both phenomena involve the collision of liquid surfaces and represent a breakdown of classical hydro dynamic theory. This paper presents computations of such non-classical phenomena using an algorithm based on a generalized theory for hydrodynamics. Under the additional assumption that liquid collisions behave inelastically, the total mechanical energy of the flow field will be reduced at the time of impact. Examples included in this paper are a comparison of computations to an exact solution of the energy loss resulting from a face-on collision of liquid cylinders, and a computational convergence study of the energy loss due to a liquid jet within a bubble impacting a solid wall. A computation of the dynamics of a shallow depth bubble is also presented.

Research supported by the Office of Naval Research under Contract N0001493WX24233, and the Naval Surface Warfare Center Independent Research Fund.