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Related papers: Bubble cloud dynamics in an ultrasound field

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The dynamic response of a gas bubble entrapped in a cavity on the surface of a submerged solid subject to an acoustic field is investigated in the linear approximation. We derive semi-analytical expressions for the resonance frequency,…

Turbulent mixing and entrainment at the boundary of a cloud is studied by means of direct numerical simulations that couple the Eulerian description of the turbulent velocity and water vapor fields with a Lagrangian ensemble of cloud water…

Fluid Dynamics · Physics 2013-10-14 Bipin Kumar , Joerg Schumacher , Raymond A. Shaw

Ultrasound contrast imaging is a specialized imaging technique that applies microbubble contrast agents to traditional medical sonography, providing real-time visualization of blood flow and vessels. Gas-filled microbubbles are injected…

Analysis of PDEs · Mathematics 2024-12-17 Vanja Nikolić , Teresa Rauscher

In this paper, we present a theoretical, experimental, and numerical study of the dynamics of cavitation bubbles inside a droplet suspended in another host fluid. On the theoretical side, we provided a modified Rayleigh collapse time and…

Fluid Dynamics · Physics 2024-01-02 Shuai Li , Zhesheng Zhao , A-Man Zhang , Rui Han

The properties of bubble-laden turbulent flows at different scales are investigated experimentally, focusing on the flow kinetic energy, energy transfer, and extreme events. The experiments employed particle shadow velocimetry measurements…

Fluid Dynamics · Physics 2022-03-02 Tian Ma , Hendrik Hessenkemper , Dirk Lucas , Andrew D. Bragg

We conduct experiments in a turbulent bubbly flow to study the nature of the transition between the classical $-$5/3 energy spectrum scaling for a single-phase turbulent flow and the $-$3 scaling for a swarm of bubbles rising in a quiescent…

This work reports an experimental characterisation of the flow properties in a homogeneous bubble swarm rising at high-Reynolds-numbers within a homogeneous and isotropic turbulent flow. Both the gas volume fraction {\alpha} and the…

Fluid Dynamics · Physics 2017-10-11 Elise Almeras , Varghese Mathai , Detlef Lohse , Chao Sun

Cavitation and bubble dynamics are central concepts in engineering, the natural sciences, and the mathematics of fluid mechanics. Due to the nonlinear nature of their dynamics, the governing equations are not fully solvable. Here, the…

Fluid Dynamics · Physics 2014-10-15 Alexander R. Klotz

Bubble dynamics and luminol emissions of cavitation in sub-millimeter-sized PFA flow tubes, submerged in an ultrasonic bath reactor, are studied at 27 kHz driving frequency. Nucleation of cavitation inside the tubes only takes place via a…

Ultrasonic atomization is employed to generate size-controllable droplets for a variety of applications. Here, we minimize the number of parameters dictating the process by studying the atomization of a single drop pending from an…

In this work, a mathematical model based on interface energy is proposed within the framework of surface continuum mechanics to study the dynamics of encapsulated bubbles. The interface model naturally induces a residual stress field into…

Fluid Dynamics · Physics 2023-06-22 Nehal Dash , Ganesh Tamadapu

Bubbles and droplets are ubiquitous in many areas of engineering, including microfluidics where they can serve as microreactors for screening of chemical reactions. They are often formed out of a constriction (a microfluidic channel or a…

Fluid Dynamics · Physics 2022-10-18 Marc Grosjean , Elise Lorenceau

Ultrasound offers promising applications in biology and chemistry, but quantifying local ultrasound conditions remains challenging due to the lack of non-invasive measurement tools. We introduce antibubbles as novel optical reporters of…

Surface bubbles have attracted much interest in the past decades. In this article, we propose to explore the lifetime and thinning dynamics of centimetric surface bubbles. We study the impact of the bubbles size as well as that of the…

Soft Condensed Matter · Physics 2020-05-28 Jonas Miguet , Marina Pasquet , Florence Rouyer , Yuan Fang , Emmanuelle Rio

Ultrasound-driven microbubbles rectify oscillatory motion into strong steady streaming flow [1, 2]. In this fluid dynamics video, we show size-dependent trapping, focusing and sorting of microparticles, utilizing the interaction between…

Fluid Dynamics · Physics 2010-10-19 Cheng Wang , Shreyas Jalikop , Sascha Hilgenfeldt

Polymer droplets subjected to a heated environment have significance in several fields ranging from spray drying and powder formation to surface coating. In the present work, we investigate the evaporation of a high viscoelastic modulus…

Soft Condensed Matter · Physics 2023-09-28 Gannena K S Raghuram , Durbar Roy , D Chaitanya Kumar Rao , Aloke Kumar , Saptarshi Basu

The nonlinear dynamic behaviour of microscopic bubbles near a wall is investigated. The Keller-Miksis-Parlitz equation is adopted, but modified to account for the presence of the wall. This base model describes the time evolution of the…

Fluid Dynamics · Physics 2012-06-14 Sergey A. Suslov , Andrew Ooi , Richard Manasseh

In these fluid dynamics videos, we show how bubbles flowing in a thin microchannel interact under an acoustic field. Because of acoustic interactions without direct contact, bubbles self-organize into periodic patterns, and spontaneously…

Fluid Dynamics · Physics 2010-10-18 P. Marmottant , D. Rabaud , P. Thibault , M. Mathieu

Data from Direct Numerical Simulations of disperse bubbly flows in a vertical channel are used to study the effect of the bubbles on the carrier-phase turbulence. A new method is developed, based on the barycentric map approach, that allows…

Fluid Dynamics · Physics 2021-10-04 Tian Ma , Bernhard Ott , Jochen Frohlich , Andrew D. Bragg

The non-linear dynamics of driven oscillations in the size of a spherical bubble are mapped to the dynamics of a Newtonian particle in a potential within the incompressible liquid regime. The compressible liquid regime, which is important…

Fluid Dynamics · Physics 2024-12-30 Uri Shimon , Ady Stern