W. Chalgham , A. C. Seibi ,
 University of Louisiana at Lafayette, Lafayette, LA, USA
Pipeline inspection tools present some limitations related to power supply which require recharging after each operation. Using batteries or tethered tools make the duration to inspect any pipeline very limited and time consuming. This paper aims at designing a spherical self-recharging untethered mobile ball flowing inside a given pipeline using the COMSOL Multiphysics® software. The ball will ...
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 ...
郁殿龙 , 温激鸿 , 尹剑飞 ,
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 ...
S. K. Kamilla , G. Parag , H. Tripathy , P. Pattanaik ,
 Semiconductor Research Lab, ITER, Siksha 'O' Anusandhan University, Bhubaneswar, Odisha, India
The attempt has taken to miniaturized size of non contact temperature sensor by using ultrasonic trans-receiver. The piezoelectric material is used in both transmitter and receiver ends for this ultrasonic Micro-Electronics Mechanical Systems (MEMS) based temperature sensing device. Prior to fabrication of ultrasonic MEMS device, design and simulation are extensively used to avoid wastage of ...
P. Bonfiglio and F. Pompoli
Materiacustica S.r.l., Ferrara, Italy
Engineering Department, University of Ferrara, Ferrara, Italy
The present work deals with a numerical investigation of resonating systems used for noise control applications. In literature one can find analytical models based on fluiddynamics concepts for evaluating losses occurring across the holes of the perforates. In the paper an acoustical formulation based on the equivalent dissipative fluid approach will be analyzed. It will be firstly applied to ...
R. De Luca[1,2], J. Fromageau, H.W. Chan, F. Marinozzi, J. Bamber
Institute of Cancer Research and Royal Marsden Hospital, Sutton, England, United Kingdom
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, ...
T. H. Hanley, H. T. D. Grigg, B. J. Gallacher
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 ...
Qingwei Liu , Hangjie Mo 
 Shanghai Jiao Tong University, Shanghai, China
This paper studies the application of laminate magnetoelectric (ME) material in displacement sensor. We studied the L-L block composite thanks to designed structure by coupling displacement signal with the displacement potential of ME composite. A nonlinear approximation is adapted to modeling magnetostrictive phase and implemented in COMSOL Multiphysics® software. The simulation results ...
Design and Simulation of an Orbiting Piezoelectric MEMS Gyroscope Based on Detection of Phase-Shift Signals - new
S. Gorelick, J. R. Dekker, B. Guo, H. Rimminen
 VTT Technical Research Centre of Finland, Espoo, Finland
The feasibility of phase-sensitive detection of angular-rates using bi-directional orbiting piezoresonators suspended by thick annular springs with thin-film aluminium nitride piezoactuators on top of them was investigated. The ring-shaped flexures are more suitable for supporting the orbiting motion due to their angle-dependent spring constant. The response of the orbiting resonators to ...
R. Langkemper , R. Külls , J. Wilde , S. Nau , S. Schopferer ,
 Fraunhofer-Institut für Kurzzeitdynamik, Ernst-Mach-Institut, EMI, Freiburg, Germany
 Albert-Ludwigs-Universität Freiburg, Institut für Mikrosystemtechnik, Freiburg, Germany
Acceleration is an important quantity to be measured in high-speed dynamics. A new piezoresistive sensor for the measurement of high-amplitude, short-duration transient accelerations of up to 100,000 g has been developed at the Fraunhofer EMI. Its figure of merit (sensitivity x resonance frequency²) is about one order of magnitude higher than that of comparable state-of-the-art sensors. ...