Simulations of pressure pulse-bubble interaction using the boundary element method

摘要

The Boundary Element Method (BEM) is used to simulate the interaction of a bubble with a pressure pulse which resembles a shock wave. The main advantage of this model lies in its enormous speed-up in calculation as compared with other existing methods. The pulse in question is in the form of a step-pulse function with variable width and is incorporated into the Bernoulli equation. Its interaction with a bubble induces the formation of a high-speed jet that accelerates in the pulse direction. Since the dynamic response of the bubble is assumed to be mainly inertia-controlled, the compressibility effect of the surrounding water is neglected. The validation of this methodology comes from the reasonable agreement of the results with those from other established numerical simulations; namely, the Arbitrary Lagrangian Eulerian (ALE) method, the Free Lagrange Method (FLM), and experiments. Detailed comparisons in terms of bubble-shape transformation, collapse times, and jet velocities are discussed.