相关论文: Controlling the dynamics of cloud cavitation bubbl…
Sound absorption at low frequencies still remains a challenge in both scientific research and engineering practice. Natural porous materials are ineffective in this frequency range, as well as acoustic resonators which present too narrow…
We compare the computational performance of two modeling approaches for the flow of dilute cavitation bubbles in a liquid. The first approach is a deterministic model, for which bubbles are represented in a Lagrangian framework as advected…
Vaporization of low-boiling point droplets has numerous applications in combustion, process engineering and in recent years, in clinical medicine. However, the physical mechanisms governing the phase conversion are only partly explained.…
The acoustic coupling between two air bubbles immersed in water is clearly demonstrated. The system is acoustically forced, and its response is detected. The experimental results confirm that both theoretically predicted eigenmodes,…
We study quantum feedback cooling of atomic motion in an optical cavity as a prototypical nonlinear quantum control problem. We design a feedback algorithm that can cool the atom to the ground state of the optical potential with high…
Flow topology and unsteady cavitation dynamics in the wake of a backward facing step was investigated using high speed videography and time-resolved X-Ray densitometry, along with static and dynamic pressure measurements. The measurements…
A self-consistent saturation model for the prediction of aeroacoustic limit cycles emerging in turbulent low-Mach cavity flows (Re=O(10^5), M\simeq 0.2) is proposed. It predicts the nonlinear interactions between the acoustic modes of a…
We propose a computational framework for the self-consistent dynamics of a microsphere system driven by a pulsed acoustic field in an ideal fluid. Our framework combines a molecular dynamics integrator describing the dynamics of the…
This work investigates the fundamental role of cavitation bubble clouds in stone comminution by focused ultrasound. The fragmentation of stones by ultrasound has applications in medical lithotripsy for the comminution of kidney stones or…
Cavitation is a limiting phenomenon in many domains of fluid mechanics. Instabilities of a partial cavity developed on an hydrofoil, a converging-diverging step or in an inter-blade channel in turbomachinery, have already been investigated…
This paper presents a study of the forced acoustical response of an open cavity from the perspective of modal expansion. Based on the coupled mode theory, it is shown that the sound pressure distribution of an open cavity excited by a point…
A growing class of ultrasound-mediated diagnostic and therapeutic technologies, including sonoporation and blood-brain barrier modulation, relies on microbubble contrast agents, where precise control of microbubble dynamics governs…
Cavitation is a ubiquitous phenomenon in nature and bubble dynamics in open spaces have been widely studied, but the effects of the wall on the dynamics of cavitation bubbles in confined spaces are still unclear. Here, the dynamics of…
Bubble nucleation in water induced by boiling, gas supersaturation or cavitation usually originates from pre-existing gas cavities trapped into solid defects. Even though the destabilization of such gas pockets, called nuclei, has been…
We present a phase-based framework for reducing the pressure fluctuations within a spanwise-periodic supersonic turbulent cavity flow with an incoming free-stream Mach number of 1.4 and a depth-based Reynolds number of 10,000. Open cavity…
We conduct experiments and numerical simulations of the dynamics of bubble clouds nucleated on the surface of an epoxy cylindrical stone model during burst wave lithotripsy (BWL). In the experiment, the bubble clouds are visualized and…
Water at negative pressures can remain in a metastable state for a surprisingly long time before it reaches equilibrium by cavitation, i.e. by the formation of vapor bubbles. The wide spread of experimentally measured cavitation pressures…
The pressure wave emitted from the air gun contains many frequencies, among which the low-frequency waves are desirable for exploration and imaging, while the high-frequency waves need to be suppressed as they are harmful to marine species.…
A vortices-bubble system may be depicted by some features which may lead to infer its acoustic charge and its spin angular momentum. We study the dynamics of this system within the framework of fluid physics and with the help of Maxwell's…
Understanding the acoustic cavitation threshold is essential for minimizing cavitation bioeffects in diagnostic ultrasound and for controlling cavitation--mediated tissue ablation in focused ultrasound procedures. The homogeneous cavitation…