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...

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...

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...

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...

An investigation of the multi-cycle dynamics underwater explosion bubbles near hybrid boundaries is conducted using experimental method. The experiments are carried out within a square steel tank. free surface and freely hanging plate comprise boundary condition. Bubbles initially positioned at equal distances from two to facilitate comparison relative influence exerted by each boundary. High-speed photography pressure sensors utilized document pressures in flow field. examination bubble...

This work investigates the effects of fluid compressibility related to bubble migration. These are described based on a theoretical model for compressible dynamics that considers phase transition and migration, as proposed by Zhang. Bubble experiments different types conducted validate this further. The well captures experimental results near wall free surface, illustrating neglecting migration in overestimating maximum radius period during second oscillating cycle. Disregarding higher peak...

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 jet characteristics of bubbles near mixed boundaries have been the focus research in many fields. As associated parameters are complicated, relatively few reports published. In this paper, a numerical model is established by considering influence free surface and mutual vertical wall using boundary element method. To determine collapsing different areas, two nondimensional must be investigated: distance γv from bubble to γh horizontal wall. At same time, buoyancy parameter δ cannot...

The silkworm (Bombyx mori) has served humankind through silk protein production. However, traditional sericulture and the industry have encountered considerable bottlenecks must rely on major technological breakthroughs to keep up with current rapid developments. adoption of gene editing technology nevertheless brought new hope industry. long period low efficiency genetic breeding methods obtain high silk-yielding strains hindered development industry; use specifically control expression...

The dynamics of a buoyant pulsating bubble near two crossed perpendicular rigid boundaries (a horizontal and vertical wall) are studied using the boundary element method combined with mirror images. Kelvin impulse elastic mesh velocity used to calculate direction volume liquid jet generated during collapse. numerical results show good agreement experiments. An increase in buoyancy causes local high-pressure zone at root move toward bottom bubble, causing rotate upward wall. At certain...

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 coupling effect between a pulsating bubble and free surface near rigid structure is complicated physical process. In this study, the evolution of an underwater explosion modeled by boundary integral method. An approach "double-node method" used to maintain stability fluid-structure junction in simulations, meshes on are transformed open domain ensure calculation accuracy efficiency. Validations conducted against experiment structure. As result, simulations trace jetting behavior rise...

Tetrastigma hemsleyanum Diels & Gilg ( T. ) has attracted much attention due to its ability on pneumonia, bronchitis, and immune-related diseases, while functional components underlying mechanism of action pneumonia have not been fully elucidated. Herein, we used a systematic network pharmacology approach explore the leaf in treatment pneumonia. In this study, results demonstrated that there were 34 active 80 drug–disease targets leaf, which strongly connection with signal...

A machine learning method is proposed to predict the collapse patterns and flow field state of underwater explosion bubbles subjected vertical sidewall free surface, which can overcome limitations high costs traditional experimental tests long computation times numerical simulations. The dataset was obtained by boundary element method, including cases bubble with different buoyancy parameters at distances from surface sidewall. Due strong geometric nonlinearity influenced boundary, three...

This study is concerned with the dynamic characteristics of bubbles near two connected walls (one horizontal and other inclined an obtuse angle from one). In this study, we set up experiment system to conduct typical cases, boundary element method employed explain bubble behavior effect relative parameters. Comparing mutually perpendicular walls, find that liquid jet deviates direction within a much shorter range. On intersection motions have similar trends. The relatively low pressure...

Over Antarctica, surface fluxes play an important role in the local atmospheric dynamical processes. To reveal characteristics and aerodynamic thermal roughness lengths over Zhongshan station, this paper analyzes data observed at station during 3 March 2008 through 15 February 2009. It is found that easterlies dominated site throughout whole year, with a maximum (average) speed of 25 (5.6) m s−1 3.9 height, annual (minimum) temperature reached 291.05 (230.05) K, while air-specific humidity...

A numerical model considering the bubble, rigid wall and free surface is established by using boundary element method (BEM). We concentrate on influence between a bubble near with 30 degrees to vertical plane. conduct this study from two aspects. First, effect of position, dimensionless distance parameter delimited: γh denoting initial plane crossing wall. find that for large-scale bubbles, liquid jets form at collapsing stage change in height found rely γh. At small reaches its peak wall,...

Supercritical carbon dioxide (SC CO2) was used as a carrier/solvent for the "dry" alumination of mesoporous silica to prepare aluminum-containing MCM-41. The effect on structure and crystallinity materials studied. In addition, hydrothermal thermal stability this material have been investigated compared with Al-MCM-41 prepared via conventional impregnation direct synthesis. Irrespective preparation method, surface area, pore diameter, volume, all decrease after treatments. However,...

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