Inertial collapse of a single bubble near a solid surface
Shahaboddin Alahyari Beig, University of Michigan
Eric Johnsen, University of Michigan
DOI: doi.org/10.1103/APS.DFD.2018....
Cavitation research is essential to a variety of applications ranging from naval hydrodynamics to medicine and energy sciences. Sub-micron-sized cavities can grow to millimeter-sized bubbles, and collapse violently in an inertial fashion. This implosion, which concentrates energy into a small volume, can produce high pressures and temperatures, generate strong shock waves, and even emit visible light. In the vicinity of a neighboring solid the collapse becomes non-spherical, evidenced by the formation of a liquid re-entrant jet directed toward the solid. The impact of the jet upon the distal side of the bubble generates a water-hammer shock, and thus high pressure regions along the solid wall. One of the main consequences of cavitation is structural damage to neighboring objects due to bubble collapse. In this video, we simulate the collapse of a single bubble near a solid surface. We show the detailed dynamics of the flow including jet formation and shockwave propagation. Furthermore, we present scaling plots for important collapse properties (e.g., jet velocity, wall pressures) in terms of the initial stand-off distance and driving pressure, which not only illustrate universality of single bubble dynamics but also provide means to predict these phenomena.
See other videos from the 2018 Gallery of Fluid Motion: gfm.aps.org/