Article
Mechanics
Jing Luo, Weilin Xu, Boo Cheong Khoo
Summary: The study found that the relative distance and size between the cavitation bubble and air bubble play a dominant role in the stratification effect exerted by the air bubble on the shock wave. When the two bubbles merge, the energy and pressure peak of the shock wave decrease significantly to less than 40% of the original values.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Xiao-Xuan Liang, Norbert Linz, Sebastian Freidank, Gunther Paltauf, Alfred Vogel
Summary: The dynamics of spherical laser-induced cavitation bubbles in water were investigated using experimental techniques and numerical simulations. The study revealed the oscillation characteristics, gas content, and shock wave emission of the bubbles, and analyzed the motion velocity of the bubble wall and energy distribution.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Engineering, Marine
Yanwei Zhai, Weilin Xu, Jing Luo, Jianbo Li
Summary: This paper studies the interaction between cavitation bubbles and different elastic boundaries from the perspective of microjets and shock waves. The elastic deformation characteristics of elastic materials under the penetration of microjets are found to be the main influencing factors of cavitation erosion.
Article
Mechanics
Qianxi Wang, Wenke Liu, Callan Corbett, Warren R. Smith
Summary: This article presents a grid-free and robust model for simulating the non-spherical oscillation or surface modes of microbubbles under ultrasound. By introducing a viscous pressure correction and using the boundary integral method, the model incorporates compressible and viscous effects and shows good agreement with theoretical and experimental results.
Article
Acoustics
Jinsen Hu, Xuan Lu, Yifan Liu, Jingfei Duan, Yuhang Liu, Jiaxin Yu, Xiaoxiao Zheng, Yuning Zhang, Yuning Zhang
Summary: This paper investigates the jet dynamics and shock waves induced by the cavitation bubble collapsing near two spherical particles using OpenFOAM. The numerical results are validated by experimental data obtained from a high-speed camera cavitation system. The study reveals that bubble split induced by annular jet is the primary feature during bubble collapsing. The localized high pressure produced at the bubble split point is the main reason for jet formation and also serves as the source of the shock waves.
ULTRASONICS SONOCHEMISTRY
(2023)
Article
Engineering, Marine
Rui-Nan Cui, Shuai Li, Shi-Ping Wang, A-Man Zhang
Summary: In this study, the dynamics of high-pressure pulsating bubbles near a concave surface were investigated using experimental and numerical methods. Detailed information on bubble shapes, jet velocity, and wall pressure were obtained, and the validity of the numerical model was confirmed.
Article
Engineering, Marine
Zhen-Yu Hu, Shuai Li, Shi-Ping Wang, A-Man Zhang
Summary: In this study, the nonlinear bubble-plate interaction and the effect of fluid-structure interaction are investigated using boundary integral simulations and experiments. Different bubble collapse patterns and the impact of FSI on jet velocity and pressure are identified. Two scaling laws for plate motion with respect to geometry parameters are proposed.
Article
Computer Science, Interdisciplinary Applications
Shuai Li, A-Man Zhang, Rui Han
Summary: The study establishes an accurate and inexpensive three-dimensional boundary integral (BI) model for the dynamics of cavitation bubbles in binary immiscible fluid systems. The model is found to be comparable in accuracy to a 3D axisymmetric model and shows good agreement with experimental results. The study also investigates the interactions between two bubbles in different phases, revealing the effects on bubble morphologies, flow patterns, and jet velocities, as well as the differences in fluid mixing mechanisms between multiple bubbles and a single bubble.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Mechanics
Aditya Madabhushi, Krishnan Mahesh
Summary: We propose a compressible multi-scale model that captures the dynamics of both large vapour cavities and micro-bubbles and takes into account the compressibility of the medium. The model tracks the homogeneous mixture of liquid and resolved vapour in an Eulerian sense and tracks the unresolved vapour in a Lagrangian sense using a novel equation. The model has been validated and shown to accurately capture the collapse of single and multiple bubbles, as well as the interaction between bubbles in a cluster.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Acoustics
Fabian Reuter, Carsten Deiter, Claus -Dieter Ohl
Summary: This study reveals the mechanism behind energy focusing during the non-spherical collapse of cavitation bubbles, leading to the erosion of hardened metals. Using high-speed imaging and shockwave recording, the conditions for this focusing process and its damage to solids are resolved.
ULTRASONICS SONOCHEMISTRY
(2022)
Article
Mechanics
Ulisses J. Gutierrez-Hernandez, Fabio De Colle, Claus-Dieter Ohl, Pedro A. Quinto-Su
Summary: In this work, a Fresnel-lens-inspired method is proposed and demonstrated for focusing multiple laser-induced shock waves through time-delay superposition at arbitrary locations. The method has been successfully demonstrated experimentally, showing effectiveness under specific geometric conditions and good agreement with simulation results.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Mohammad Khavari, Abhinav Priyadarshi, Andrew Hurrell, Koulis Pericleous, Dmitry Eskin, Iakovos Tzanakis
Summary: This study investigates the shock wave pressures emitted by cavitating bubbles in water under ultrasonic excitation, revealing a resonance peak at a narrow range of frequencies and suggesting its association with shock wave emissions from collapsing bubbles. Results show an increasing pressure shielding effect with higher input power.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Ulisses J. Gutierrez-Hernandez, Hendrik Reese, Claus-Dieter Ohl, Pedro A. Quinto-Su
Summary: Researchers have discovered that acoustic cavitation at high frequencies can be achieved through wave propagation in a solid medium. By nucleating cavitation bubbles at nano-sized fractures on a glass substrate and driving their expansion with a leaky Rayleigh wave, and their collapse with a trailing shock wave, the lifetime of the bubbles can be controlled. Experimental results align with simulation models.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Acoustics
Darja Horvat, Vid Agrez, Tomaz Pozar, Bojan Starman, Miroslav Halilovic, Rok Petkovsek
Summary: This study investigated the generation of secondary cavitation following laser-induced breakdown in spherical media. Through numerical simulation and experimental comparison, it was found that significant transient negative pressure and pre-illumination by breakdown-generating laser pulses played important roles in the generation of secondary cavitation.
ULTRASONICS SONOCHEMISTRY
(2022)
Article
Mechanics
Wangxia Wu, Qingquan Liu, Bing Wang
Summary: The study numerically investigates high-speed droplet impingement on typical curved surfaces to analyze complex wave structures and cavitation. The analysis includes the evolution of confined shock waves, cavities, and pressure distribution on concave, convex, and flat surfaces, showing different impacts on shock wave strength and cavitation behavior.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mathematics, Interdisciplinary Applications
Dalei Jing, Jian Song, Yi Sui
FRACTALS-COMPLEX GEOMETRY PATTERNS AND SCALING IN NATURE AND SOCIETY
(2020)
Article
Thermodynamics
Yang Ma, Yongpan Cheng, Yang Shen, Jinliang Xu, Yi Sui
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2020)
Article
Mechanics
K. Ashoke Raman, Erik Birgersson, Yi Sui, Adrian Fisher
Article
Mechanics
Qianxi Wang, Mehdi Mahmud, Jie Cui, Warren R. Smith, A. D. Walmsley
Article
Acoustics
K. M. A. Manmi, W. B. Wu, N. Vyas, W. R. Smith, Q. X. Wang, A. D. Walmsley
ULTRASONICS SONOCHEMISTRY
(2020)
Article
Multidisciplinary Sciences
N. Vyas, R. L. Sammons, S. A. Kuehne, C. Johansson, V Stenport, Q. X. Wang, A. D. Walmsley
Article
Acoustics
Jie Cui, Zhi-Peng Chen, Qianxi Wang, Tao-Ran Zhou, Callan Corbett
ULTRASONICS SONOCHEMISTRY
(2020)
Article
Mechanics
W. R. Smith, Q. X. Wang
Summary: Numerical simulations of violent bubble dynamics often encounter numerical instabilities due to two time scales associated with the phenomenon, as revealed by the Keller-Miksis equation. The short time scale for significant acoustic radiation emission from the bubble has been determined and validated through comparison with experimental results.
FLUID DYNAMICS RESEARCH
(2021)
Article
Mechanics
Tao Lin, Zhen Wang, Ruixin Lu, Wen Wang, Yi Sui
Summary: In this study, a novel efficient method combining a deep convolutional neural network with a high-fidelity mechanistic capsule model is proposed to predict the membrane viscosity and elasticity of microcapsules flowing in a branched microchannel. Compared with traditional methods, this approach significantly increases prediction throughput rate while maintaining accuracy, and can handle capsules with large deformation in inertial flows.
Article
Acoustics
N. Vyas, Q. X. Wang, A. D. Walmsley
Summary: This study investigated the use of carbonated water to enhance cavitation generated by ultrasonic scalers for improved biofilm removal from dental implants and other biomaterials. Results showed that cavitation significantly increased and accelerated in carbonated water, leading to more effective biofilm removal. This suggests a potential clinical application for using carbonated water to enhance cavitation and improve biofilm cleaning.
ULTRASONICS SONOCHEMISTRY
(2021)
Article
Mechanics
Shi-Min Li, Yun-Long Liu, Qianxi Wang, A-Man Zhang
Summary: This study investigates the dynamics of a buoyant pulsating bubble near two crossed perpendicular rigid boundaries, and the numerical results show good agreement with experiments. It is found that an increase in buoyancy leads to a change in jet direction, exhibiting different characteristics at different standoff distances between the walls.
Article
Physics, Applied
Kewen Peng, Frank G. F. Qin, Runhua Jiang, Wanjun Qu, Qianxi Wang
Summary: Reactive species (RS) play a critical role in postoperative complications in laser surgery. Through simulation calculations, it has been found that the concentration of RS produced in collapsing bubbles is relatively high, and the generation mechanism mainly involves the decomposition of hydrogen peroxide and reactions between hydrogen, oxygen, and various free radicals. Furthermore, the production of RS increases with pulse energy. These findings can contribute to the development of strategies to mitigate complications or exploit the benefits associated with RS in laser surgery.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Mechanics
Warren R. Smith, Qianxi Wang
Summary: Small viscous effects in high-Reynolds-number rotational flows accumulate over time to have a leading-order effect, making the high-Reynolds-number limit for the Navier-Stokes equations singular. Investigating whether a solution of the Euler equations can approximate a real flow at large Reynolds number is crucial. The neglect of these facts leads to the use of Euler equations to simulate laminar rotational flows at large Reynolds number.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Qianxi Wang, Wenke Liu, Callan Corbett, Warren R. Smith
Summary: This article presents a grid-free and robust model for simulating the non-spherical oscillation or surface modes of microbubbles under ultrasound. By introducing a viscous pressure correction and using the boundary integral method, the model incorporates compressible and viscous effects and shows good agreement with theoretical and experimental results.
Correction
Mechanics
Q. X. Wang