In this work, we established a novel theory for the dynamics of oscillating bubbles such as cavitation bubbles, underwater explosion and air bubbles. For first time, proposed bubble equations that can simultaneously take into consideration effects boundaries, interaction, ambient flow field, gravity, migration, fluid compressibility, viscosity, surface tension while maintaining unified elegant mathematical form. The present unifies different classical Rayleigh-Plesset equation, Gilmore...

High-speed water entry is a transient hydrodynamic process that accompanied by strongly compressible flow, free surface splash, cavity evolution and other nonlinear phenomena. To address these problems, novel fluid–structure interaction (FSI) scheme based on the immersed boundary method proposed which suitable for multiphase flows. In this scheme, considering interfaces at boundary, an improved effectively suppressing non-physical force oscillation proposed. Additionally, quaternion-based...

Vertically neutral collapse of a pulsating bubble occurs when the boundaries above or below balance buoyancy effect over pulsation. In this study, vertically near vertical rigid wall free surface is investigated. The boundary integral method (BIM) employed to model dynamics with an open-domain surface. Moreover, validated against several buoyant experiments. Bubble in such conditions are associated three dimensionless parameters: bubble-free distance $\gamma _{{f}}$ , bubble–wall _{{w}}$ and...

Abstract This paper aims to use the unified bubble dynamics equation investigate behavior in complex scenarios involving hybrid free surface/wall boundaries and interactions between multiple bubbles. The effect of singularity movement on equation’s form is analyzed after deriving pulsation using a moving point source dipole, followed by discussions migration compressibility-related terms dynamics. In addition, present study accounts for impact boundaries, including crossed parallel...

A novel theoretical model for bubble dynamics is established that simultaneously accounts the liquid compressibility, phase transition, oscillation, migration, ambient flow field, etc. The equations are presented in a unified and concise mathematical form, with clear physical meanings extensibility. oscillation equation can be simplified to Keller–Miksis by neglecting effects of transition migration. present effectively captures experimental results bubbles generated free fields, near...

The evolution of the water-entry cavity affects impact load and motion body. This paper adopts Eulerian finite element method for multiphase flow simulations high-speed process. accuracy convergence numerical are verified by comparing it with experimental data results transient dynamics theory. Based on results, representative characteristics discussed from perspective cross-section. It is found that asymmetry expansion contraction durations related to free surface closure cavity. uplift...

The treatment of material interface and cavitation in compressible flow brings difficulties challenges for numerical simulation, which is also a research field great significance. Therefore, we present discontinuous Galerkin (DG) method to simulate multiphase by combining the γ-based model cutoff model. DG scheme adopted spatial discretization on an unstructured mesh, positivity-preserving limiter extended ensure parabolicity system. Then eigenvectors Jacobian matrices obtained replacing...

Carbon-MXene heterostructures with increased interlayer spacing and surface defects show excellent electrochemical performance for supercapacitor electrodes.

The shock wave and bubble dynamics of an underwater explosion are significant in various fields. When the charge is non-spherical, detonation process will remarkably affect formation subsequent motion. In this work, a cylindrical explosive investigated numerically with Eulerian finite-element method combined programed burn model treating process. present validated by comparing simulated results experimental ones. Then, several cases different slenderness buoyancy environments analyzed....

The interaction between an underwater explosion bubble and elastic-plastic structure is a complex transient process, accompanying violent collapsing, jet impact, penetration through the bubble, large structural deformation. In present study, dynamics are modeled using boundary element method nonlinear response explicit finite method. A new fully coupled 3D model established coupling equations for state variables of fluid solving them as set linear algebra equations. Based on acceleration...

Dynamics behavior for a submerged oscillating bubble is closely related to the physical properties of boundaries adjacent bubble. For an incomplete boundary, such as ship structure broken by shock wave from underwater explosion attack, load formed after may cause secondary damage it, and jet characteristics generated during collapse are worth exploring. Based on incompressible potential flow method, boundary integral method with axisymmetric code employed investigate features under combined...

This paper presents numerical investigations of the nonlinear interactions between two underwater explosion (UNDEX) bubbles using compressible Eulerian finite-element method (EFEM). The volume fluid is applied to capture multi-fluid interface. In this model, high-temperature and high-pressure gaseous products inside UNDEX bubble are described by equation state for Jones–Wilkins–Lee, which allows us consecutively simulate propagation primary shock wave multi-period pulsations. To verify...

The jetting behaviour and migratory characteristics of a laser-induced cavitation bubble in rectangular channel are investigated both experimentally numerically, for various combinations the geometric physical parameters system. High-speed photography is used to visualize temporal development shape, formation liquid jets during collapse, displacement contact with sidewalls two oscillation cycles bubble. profiles, pressure contours velocity vectors ambient obtained through numerical...

The interaction of multiple bubbles is a complex physical problem. A simplified case studied theoretically with bubble located at the center circular cluster. All in cluster are equally spaced and own same initial conditions as central bubble. unified theory for dynamics (Zhang et al. arXiv:2301.13698) applied to model between To account effect propagation time pressure waves, emission source wave obtained by interpolating information on axis. An underwater explosion experiment two different...

The numerical modelling of 3D toroidal bubble dynamics is a challenging problem due to the complex topological transition flow domain, and physical instabilities, associated with jet penetration through bubble. In this paper, phenomenon modelled using boundary integral method (BIM) coupled vortex ring model. We implement new impact model consisting refined local mesh near location immediately before after impact, surgical cut at high resolution forming smooth hole for from singly connected...

This paper is concerned with microbubble dynamics in a blood vessel surrounded by elastic tissue subject to ultrasound, which are associated important applications medical ultrasonics. Both the flow inside and external modeled using potential theory coupled boundary element method. The elasticity of through inclusion pressure term dynamic condition at interface between two fluids. Weakly viscous effects considered theory. numerical model validated comparison theoretical results...