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流体-孔隙介质周期性粗糙界面超声波反射与透射特性研究

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声学技术 2024年第2期43卷 218-223页

作者：张煜静韩庆邦苏娜娜吴洋靳琪琳孙刘家河海大学物联网工程学院江苏常州213022

为了研究超声波在流体-孔隙介质周期性粗糙界面的传播特性,文章基于周期性锯齿粗糙界面的衍射模型分析孔隙介质开孔与闭孔状态下孔隙度对反射与透射的影响。通过孔隙介质比奥特(Biot)理论与光栅方程理论,得到包含各阶反射系数、透射系... 详细信息

为了研究超声波在流体-孔隙介质周期性粗糙界面的传播特性,文章基于周期性锯齿粗糙界面的衍射模型分析孔隙介质开孔与闭孔状态下孔隙度对反射与透射的影响。通过孔隙介质比奥特(Biot)理论与光栅方程理论,得到包含各阶反射系数、透射系数的线性方程组,再利用傅里叶变换进行数值计算,得到孔隙度与流体-孔隙介质周期性粗糙界面反射系数、透射系数之间的关系。结果表明,由于界面的周期性,频率对反射与透射系数的影响没有呈现一定的规律。但孔隙度对反射与透射系数有显著影响,且由于孔隙介质状态的差异性,导致反射与透射系数在开孔与闭孔时变化趋势不同。

关键词：孔隙介质粗糙界面反射系数透射系数

Propagation characteristics of low-frequency axisymmetric waves in fluid-filled pipes embedded in the viscoelastic medium

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Chinese Journal of Acoustics 2022年第3期41卷 221-237页

作者： QIAN Jiawen han qingbang SU Nana BAI Le QIAN Xintong College of IOT Engineering of Hohai University Changzhou 213022

The propagation characteristics of the low-frequency axisymmetric waves in buried fluid-filled pipes are investigated theoretically,based on the Kennard thin-walled shell equations,the Helmholtz equation,and the Kelvin-Voigt linear viscoelastic *** expressions of the phase velocity are derived for both the fluid-dominated wave and the shell-compressed wave under lubricated contact,via considering the surrounding soil as a viscoelastic *** dispersion and attenuation curves of the two wave types are obtained and verified *** ratio of the radial pipe wall displacements is analyzed,with particular emphasis on the effects of the thickness-to-radius ratio and the quality factor on the dispersion and attenuation characteristics of the fluid-dominated *** results show that the viscoelastic property has slight effects on the phase velocities of the two wave types,but it influences the attenuation *** fluid-dominated wave influences the radial pipe wall displacement significantly and is the primary carrier of leakage noise energy;its phase velocity increases as a function of the thickness-to-radius ratio while the attenuation *** also shows that the dispersion and attenuation of the fluid-dominated wave decrease as a function of the quality *** work will provide insights and guidance for the leakage detection of buried fluid-filled pipes.

关键词： wave viscoelastic filled

Second-order harmonic field characteristics at solid-solid interface with P wave incidence

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Chinese Journal of Acoustics 2020年第4期39卷 541-551页

作者： WU Ning han qingbang HONG Xiaomin College of IOT Engineering Hohai UniversityChangzhou 213022

The second-order harmonic field characteristics at the solid-solid interface with P wave incidence were evaluated according to the second-order potential *** isotropic solid-solid interface was established to solve the boundary value problem of second-order nonhomogeneous potential equation based on the Lagrange’s method of variation parameters.A numerical computation was performed to analyze the incident angle and second-order harmonic *** results show that the longitudinal wave and transverse wave displacements of second-order harmonic field rapidly increase at a specific incidence ***,the special solutions of displacement abruptly change for incident angle θ***,the effect of boundary surface on second-order harmonic sound field is also discussed.

关键词： theory. harmonic wave

Propagation characteristics of guided waves in a liquid filled pipe embedded in a porous medium

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Chinese Journal of Acoustics 2020年第1期39卷 94-107页

作者： JIANG Jian han qingbang XU Zhouchen JIA Jing LIANG Dong ZHONG Xiaomin College of IOT Engineering of Hohai University Changzhou 213022

A model of a liquid-filled pipe embedded in a porous medium is built to research its wave propagation characteristics,and to analyze the effect of the parameters of porous media on the *** dispersion equations are established on the basis of the elastic-dynamic theory of the liquid-saturated porous *** characteristic of dispersion and the time domain waveform in pipes of different thicknesses and with different porous-medium parameters are discussed theoretically and *** reveal that the porosity has little impact on dispersion,and the attenuation of guided wave increases with porosity,whilst the porosity influences the displacement amplitude of the time domain *** is hard to detect the permeability variation of the media by the *** drawn conclusion can provide some theoretical instruction and guidance for the nondestructive testing of buried pipe.

关键词： porous filled porosity

Time difference based measurement of ultrasonic cavitations in wastewater treatment

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High Technology Letters 2016年第1期22卷 63-66页

作者：朱昌平 Wang Bin Liu Changwei Gong Runhang Liu Jing Ren Qinggong han qingbang Huang Bo Shan Minglei Tang Yibin Ni Caihua Jiangsu Key Laboratory of Power Transmission and Distribution Equipment Technology Changzhou Key Laboratory of Sensor Networks and Environmental Sensing Hohai University Changzhou 213022 P. R. China School of Petrochemical Engineering Changzhou University Changzhou 213164 P. R. China School of Chemical and Material Engineering Jiangnan University Wuxi 214122 P. R. China

Intensity of cavitation is significant in ultrasonic wastewater treatment,but is complicated to measure.A time difference based method of ultrasonic cavitation measurement is *** time differences at different powers of 495 kHz ultrasonic are measured in experiment in comparison with conductimetric *** results show that time difference and electrical conductivity are both approximately positive proportional to the ultrasonic *** degradation of PNP solution verifies the availability in wastewater treatment by using ultrasonic.

关键词：测量时间废水处理超声波空化作用超声空化效应污水处理测量方法对比试验

Interface wave propagation characteristics of liquid-immersed porous cylinder

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Chinese Journal of Acoustics 2018年第2期37卷 177-190页

作者： han qingbang XU Zhouchen TONG Ziwei QI Lihua WANG Peng Shan Minglei ZHU Changping College of IOT Engineering of Hohai University

This paper devotes to investigate the propagation characteristics of the interface wave on the liquid-immersed porous cylinder, and special emphasis is paid on the dependence of the dispersion relation on the porous media parameters. A model of liquid-immersed porous cylinder is established theoretically. Based on the elastic-dynamic theory of liquid-saturated porous solid and wave theory, the dispersion curves and transient response of open-pores and sealed-pores are simulated numerically, and their dependence on the cylinder radius and porous medium parameters are analyzed. The results show that the Stoneley-Scholte wave can be clearly distinguished with other waves in the time domain, and the Stoneley-Scholte wave dispersion relates intimately with the porosity of the porous medium and cylinder radius, whilst the permeability of the media has little effect on the dispersion property.

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Investigation of cavitation bubble collapse in hydrophobic concave using the pseudopotential multi-relaxation-time lattice Boltzmann method

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Chinese Physics B 2021年第4期30卷 333-341页

作者：单鸣雷杨雨赵雪梦韩庆邦姚澄 Jiangsu Key Laboratory of Power Transmission and Distribution Equipment Technology Hohai UniversityChangzhou 213022China College of Computer and Information Hohai UniversityNanjing 210000China

The interaction between cavitation bubble and solid surface is a fundamental topic which is deeply concerned for the utilization or avoidance of cavitation *** complexity of this topic is that the cavitation bubble collapse includes many extreme physical phenomena and variability of different solid surface *** the present work,the cavitation bubble collapse in hydrophobic concave is studied using the pseudopotential multi-relaxation-time lattice Boltzmann model(MRT-LB).The model is modified by involving the piecewise linear equation of state and improved forcing *** fluid-solid interaction in the model is employed to adjust the wettability of solid ***,the validity of the model is verified by comparison with experimental results and grid-independence ***,the cavitation bubble collapse in a hydrophobic concave is studied by investigating density field,pressure field,collapse time,and jet *** superimposed effect of the surface hydrophobicity and concave geometry is analyzed and explained in the framework of the pseudopotential *** study shows that the hydrophobic concave can enhance cavitation effect by decreasing cavitation threshold,accelerating collapse and increasing jet velocity.

关键词： cavitation bubble hydrophobic concave lattice Boltzmann model pseudopotential model

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激光激发粘弹表面波特性分析

声学学报 2007年第4期32卷 338-342页

作者：韩庆邦钱梦騄河海大学计算机与信息工程学院同济大学声学研究所上海200092

研究了粘弹Rayleigh波的传播特性。基于基本粘弹理论,推导出了粘弹Rayleigh波频散方程及位移表述式,探讨了粘弹模量对波频散特性及衰减特性的影响。发现在小粘滞的情况下,粘弹对相速度的影响不大,波的衰减和粘滞模量近似成正比,同样量... 详细信息

研究了粘弹Rayleigh波的传播特性。基于基本粘弹理论,推导出了粘弹Rayleigh波频散方程及位移表述式,探讨了粘弹模量对波频散特性及衰减特性的影响。发现在小粘滞的情况下,粘弹对相速度的影响不大,波的衰减和粘滞模量近似成正比,同样量级的体变粘滞引起的频散及衰减比切变粘滞要小很多。数值上还计算了粘弹Rayleigh瞬态波形,计算结果与理论预言一致。

关键词：粘弹理论传播特性 Rayleigh波激光激发表面波频散方程衰减特性计算结果

Modeling for Collapsing Cavitation Bubble near Rough Solid Wall by Mulit-Relaxation-Time Pseudopotential Lattice Boltzmann Model

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Journal of Applied Mathematics and Physics 2017年第6期5卷 1243-1256页

作者： Minglei Shan Yipeng Zhu Cheng Yao qingbang han Changping Zhu College of Internet of Things Engineering Hohai University Changzhou China Jiangsu Key Laboratory of Power Transmission and Distribution Equipment Technology Hohai University Changzhou China

Cavitation bubble collapse near rough solid wall is modeled by the multi-relaxation-time (MRT) pseudopotential lattice Boltzmann (LB) model. The modified forcing scheme, which can achieve LB model’s thermodynamic consistency by tuning a parameter related with the particle interaction range, is adopted to achieve desired stability and density ratio. The bubble collapse near rough solid wall was simulated by the improved MRT pseudopotential LB model. The mechanism of bubble collapse is studied by investigating the bubble profiles, pressure field and velocity field evolution. The eroding effects of collapsing bubble are analyzed in details. It is found that the process and the effect of the interaction between bubble collapse and rough solid wall are affected seriously by the geometry of solid boundary. At the same time, it demonstrates that the MRT pseudopotential LB model is a potential tool for the investigation of the interaction mechanism between the collapsing bubble and complex geometry boundary.

关键词： Cavitation Bubble Bubble Collapse Lattice Boltzmann Method Pseudopotential Model Rough Solid Wall