Here you will find presentations given at COMSOL Conferences around the globe. The presentations explore the innovative research and products designed by your peers using COMSOL Multiphysics. Research topics span a wide array of industries and application areas, including the electrical, mechanical, fluid, and chemical disciplines. Use the Quick Search to find presentations pertaining to your application area.

浅海声场建模预报

刘佳琪 [1], 朴胜春 [2], 唐骏 [2]
[1] 哈尔滨工程大学,哈尔滨,黑龙江,中国
[2] 挪威科技大学,特隆赫姆,挪威

海洋覆盖了地球表面百分之七十以上的面积,其中蕴藏着丰富的生物矿产资源,日益受到世界各国的重视。声波作为海水中传输信号的唯一载体,在浅海波导中的传播受海底和海面影响很大,当声波在浅海波导中发生折射反射和散射时,如何预报复杂海底边界条件下浅海中的传播特性对海洋开发有重要意义。针对含有声速剖面的沉积层海底、楔形海底及实际弹性海底,利用有限元理论,对二维浅海声场的传播损失进行数值模拟。应用 COMSOL Multiphysics® 软件的声压接口和声结构耦合接口,把地形数据导入软件模拟真实海底的地形。把浅海波导简化成分层矩形,信号源以点声源的形式向外发射单频信号,在模型定义处添加完美匹配层模拟无限远距离处声压场情况;对于含有声速剖面情况的波导问题,在 COMSOL 中可以较为便捷地以添加内插函数的形式进行仿真,与其他声场建模软件形成对比,突显有限理论元理论计算浅海传播损失的优势 ...

Simulation of Electrodynamic Planar Loudspeaker (EDPL) with COMSOL Multiphysics® Software

M. Asgarisabet [1,2], R. Czapla [2], J. Krueger [2], B. Sterling [2],
[1] Michigan Technological University, Houghton, MI, USA
[2] HARMAN International, Detroit, MI, USA

A simulation of an electrodynamic planar loudspeaker (EDPL) has been developed in this study with the COMSOL Multiphysics® software. Using the simulated model, effect of different parts has been studied to improve the performance. The locations of the coil and magnets have been obtained using the magnetic flux density. Then, the sound pressure level and directivity index have been obtained.

Analysis of an Air Transparent Soundproof Window System & Comparisons to Physical Test Data - new

M. Yeoman[1], V. Sivasailam[1], A. Tomar[2]
[1]Continuum Blue Ltd., Ystrad Mynach, UK
[2]Jaguar Land Rover Ltd, Coventry, UK

The design of windows and or other perforated structures which allow the free flow of air into & out of a building or system, while being fully soundproofed or attenuate certain frequencies is of great interest to architects and design engineers, where sound as a longitudinal wave, is difficult to separate it from its medium of propagation. In this work, we present the analysis of air ...

Support-Q Optimisation of a Trapped Mode Beam Resonator - new

T. H. Hanley[1], H. T. D. Grigg[1], B. J. Gallacher[1]
[1]Newcastle University, Newcastle-Upon-Tyne, UK

Introducing a disorder into a finite periodic oscillatory system induces the presence of a 'trapped mode': a mode in which the displacement field is localised to the region of the disorder. A main inhibitor to MEMS resonators achieving a high quality (Q) factor is energy radiation through the support to the substrate. The trapped modes present a way to tune this to a minimal value. An initial ...

基于超大规模并行计算的多尺度模型声振特性仿真与预报

郁殿龙 [1], 温激鸿 [1], 尹剑飞 [1],
[1] 国防科学技术大学,长沙,湖南,中国

汽车、飞行器、舰船、高速列车等工程装备中,振动和噪声问题会严重影响装备可靠性、安全性、使用寿命和人员的健康。因此,减振降噪需求迫切,相关技术和研究也得到了前所未有的重视。 国防科技大学振动与噪声控制研究团队从2003年开始,致力于基于人工周期结构理论的弹性波传播特性、调控机理及其应用探索研究。将物理学领域中声子晶体、声学超材料等人工周期结构中的新概念与工程减振降噪应用相结合,设计研发了多种声波控制器件与结构。 COMSOL Multiphysics® 声学模块的丰富接口及其处理多物理场耦合问题的强大功能,为研究团队解决复杂多尺度结构的声振特性预报和减振降噪设计提供了有力的工具。在此平台上,研究团队设计了局域共振低频吸声材料,并依托学校“天河二号”超级计算机并行计算环境,开展了元胞尺度(mm量级)到部件尺度(m量级)模型的声学特性有限元建模求解 ...

Guided Wave in Engineering Structures Using Non-Contact Electromagnetic Acoustic Transducers: A Numerical Approach for the Technique Optimisation

S. Soua[1], A. Raude[1], and T-H. Gan[1]
[1]NDT Technology Group, TWI Ltd, Cambridge, United Kingdom

There are over 10 million kilometers of pipes and pipelines around the world that carry hazardous fluids and gases. Fluids include oil, oil products, chemicals such as solvents, caustics, acids, corrosives and combustibles often at high pressure and temperature. These pipes are susceptible to corrosion if they are not protected properly by the environment or the contents. Inspection of pipes is ...

Lamb Waves in Fluid-Loaded Plates

T. Kaufmann[1], F. Kassubek[1], D. Pape [1], M. Lenner[1]
[1]ABB Corporate Research, Baden-Dättwil, Switzerland

Lamb waves are elastic waves propagating in free solid plates. In the case of plates loaded with a fluid, the equations describing these waves have to be modified to include the effects of the fluid. In our work we have tackled this problem using COMSOL Multiphysics®. We have used the two-dimensional plane strain model of the solid mechanics interface to calculate the eigenmodes of the coupled ...

A Finite Element Model of Shear Wave Propagation Induced by an Acoustic Radiation Force Impulse

R. De Luca[1,2], J. Fromageau[1], H.W. Chan[1], F. Marinozzi[2], J. Bamber[1]
[1]Institute of Cancer Research and Royal Marsden Hospital, Sutton, England, United Kingdom
[2]Sapienza University of Rome, Dept. of Mechanical and Aerospace Engineering, Rome, Italy

Shear wave elastography is an innovative technique used in combination with the traditional ultrasound imaging to improve the specificity of cancer imaging. A two-dimensional finite element model (FEM), composed of realistic boundary conditions, was developed in COMSOL Multiphysics® to simulate the propagation of shear waves induced by an acoustic radiation force impulse (ARFI) in isotropic, ...

Modeling of a Jecklin Disk for Stereophonic Recordings

G. McRobbie[1]
[1]University of the West of Scotland, Paisley, Renfrewshire, UK

The Jecklin Disk is a sound absorbing disk placed between two omnidirectional microphones. It is used to recreate some of the frequency-response, time and amplitude variations human listeners’ experience, but in such a way that the recordings also produce a useable stereo image through loudspeakers. This paper presents a finite element model able to simulate the effects on sound propagation ...

Feed-forward/Feed-backward Mechanical Amplification in the Mouse Cochlea

J. Soons[1,2], C. Steele[2], S. Puria[2]
[1]Lab of Biomedical physics, University of Antwerp, Antwerp, Belgium
[2]Department of Mechanical Engineering, Stanford University, Stanford, USA

Sound vibrations are collected from the external environment by the eardrum and are guided to the basilar membrane in the cochlea. Pressure differences in the two scalae of the cochlea result in a traveling wave on the basilar membrane. The tiny displacements are detected by the deflection of thousands of hair cells, situated along this membrane. It is hypothesized that some 3/4 of these hair ...