Bubble Raft Statistics Of Plunging Liquid Jet

When a liquid jet impinges on the surface of a deep pool of liquid, theair entrained during jet impact is pushed under and continues to flow with thecurrent. The majority of this air rises to the free surface and forms bubbles which tend to stay together as a raft. Here we study the entrainment phenomenon and the characteristics of the bubble raft formed by a continuous jet of water plunging into a large pool of water. We explore the average radius and size distributions of the bubble raft over a range Weber, Froude, and Reynolds numbers: We ∈ [100,2500], Fr ∈ [1,1500], and Re ∈ [300,3000], respectively.We study the formation and advection statistics of the free-surface bubbles, and the capillary waves generated by their intermittent popping (dissipation) events.An analogy is drawn to other non-equilibrium processes such as the turbulent energy cascade.