Modeling of Ultrasonic Transducers and Ultrasonic Wave Propagation for Commercial Applications Using Finite Elements with Experimental Visualization of Waves for Validation - new
D. R. Andrews
Cambridge Ultrasonics, Over, UK
Finite element (FE) modelling of ultrasonic propagation using COMSOL Multiphysics® simulations can be used to create images of waves. Unfortunately, in time-stepping solutions, it is possible for numerical instabilities to grow large and dominate the solution adversely. Any design of transducer that is based upon poorly-configured FE models is unlikely to perform as expected and will almost ...
Lamb Waves and Dispersion Curves in Plates and It’s Applications in NDE Experiences Using Comsol Multiphysics
P. Gómez, J. P. Fernandez, and P. D. García
Hydro-Geophysics & NDE Modeling Unit
University of Oviedo
In this paper, a model for numerically obtaining lamb wave modes and dispersion curves in plates is presented. It is shown that COMSOL Multiphysics can be employed to simulate the behavior of guided waves in dispersive plates, which is useful for NDE applications. A two dimensional steel plate (4x0.1 meters) is excited with a space-time impact point source. To model the point source, we use ...
L. Liu, W.J. Lin, H.L. Zhang
State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing, China
In this paper, we use the PDE interface of COMSOL Multiphysics® software to implement the 2.5D frequency wave-number domain method to investigate the wave propagation in a deviated borehole penetrating a transversely isotropic formation. A convolutional perfectly matched layer is realized to eliminate the reflections from the artificial truncation boundary. With this method, we can obtain the ...
M. Cobianchi, M. Rousseau
 B&W Group Ltd, Steyning, UK
While musical instruments often rely on a body which resonates on purposefully to amplify the vibration produced by a string or a membrane, such as in a violin or a guitar, loudspeaker cabinets should not contribute at all to the total sound radiation, but aim instead to be a perfectly rigid box which encloses the drive units in charge to transform the electrical signal at their terminal into ...
V. Pavelko, I. Pavelko, M. Smolyaninovs, H. Pffeifer, M. Wevers
Riga Technical University, Riga, Latvia
Catholic University Leuven, Leuven, Belgium
A problem of damage prediction in aircraft structure and its non-destructive evaluation is very important for aircraft structural health assessment. The analysis of the features of direct impact of thin-walled laminate component of aircraft was performed by COMSOL Multiphysics software. Mainly the GFRC and CFRC laminates were selected in form either thin separate plate or sandwich structure. The ...
Zhejiang Electro-Acoustic R&D Center, CAS, Zhejiang, China
扬声器的失真问题一直受电声业界的关注，尤其是谐波失真，它是影响扬声器重放声音音质的主要因素之一。 本文提出了一种基于 COMSOL Multiphysics® 软件预测扬声器谐波失真的仿真分析方法。该方法需建立包括磁场、振动系统和声场等多个物理场的扬声器的全模型，给扬声器加载一单频电压信号，用瞬态分析的方法可求解得到该频率激励下的扬声器的多个重要物理量随时间的变化函数，如流经音圈的电流I(t)、音圈的受力F(t)、振动系统表面上任意点的位移x(t)，以及声场中任意点的声压P(t)等。给扬声器加载一个时间长度为0.1s的单频电压信号，仿真分析所得的防尘帽顶点的位移曲线 x(t) 如图1所示，图2则是对应的在扬声器正前方0.1m处的声压曲线 P(t)。 再对所得的声压信号的稳态部分做FFT频谱分析，便可获得输入信号的各阶次谐波分量 ...
A. Prasad , R. C Thiagarajan ,
 ATOA Scientific Technologies, Bengaluru, India
This paper deals with the numerical experiments for early prediction of muffler performance at the design stage. In this experiment, a Reactive Muffler is developed and validated numerically compared to traditional built and test process.
Simulation of a New PZT Energy Harvester with a Lower Resonance Frequency Using COMSOL Multiphysics® - new
H. Elbahr, T. Ali[1,2], A. Badawi, S. Sedky
Zewail City of Science and Technology - Cairo, Cairo, Egypt
Cairo University, Cairo, Egypt
Energy harvesting from environmental vibration nowadays is feasible because of natural oscillations like that caused by air or liquid flow and by exhalation or the heartbeat of a human body. This vibration frequency is typically low (in order of less than 1 kHz). Accordingly, low-frequency vibration based energy harvesting systems are an important research topic; these systems can be used for ...
R. Balistreri ,
 QSC Audio Products, LLC., Costa Mesa, CA, USA
This paper utilizes lumped circuits equivalent and pressure acoustics to simulate the behavior of a PA loudspeaker in order to improve its design.
D. Neihguk , A. Prasad ,
 Mahindra & Mahindra Ltd., Chennai, India
The acoustic performance of an acoustically short Concentric Tube Resonator (CTR) is investigated to find an optimum porosity for a given length to diameter ratio. The study is motivated by the following practical difficulties encountered in automotive exhaust noise control: 1. Increasing trend of downsized engine and increase in power to weight ratio of engine for better fuel economy. 2. The ...