L. Martinelli, and A. Lamberti
Universita di Bologna, Italy
Objective of this contribution is to show how to implement the Mild Slope Equations with COMSOL Multiphysics. These equations are commonly used to study the propagation of waves in harbors. Some interesting features are presented, namely the use of weak terms (used for the modelling of the source term); the evaluation of a smooth phase gradient from the complex dependent variable; a robust ...
J. M. Stauber , B. A. Marmo ,
 Xi Engineering Ltd, Edinburgh, United Kingdom
Tonal noise from wind turbines can have effects on neighboring residences and its emission can result in strong regulatory penalties that can include the closure of wind farms. The authors present a model of a new broadband damping approach where containers filled with EniDamp™, an Advance Particle Damping (APD) material. The containers, so-called APD pods, are magnetically fixed to wind ...
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 ...
SRM University & BITS Pilani University, Chennai, Tamil Nadu, India
Vibration analysis of perforated plates is extremely important when designing structures where resonance is the possible mode of failure. This paper deals with the vibration analysis of rectangular perforated plates with three different types of perforations. Vibration analysis is to be carried out by both COMSOL Multiphysics® Software and Experimental set-up. The applications of perforated ...
L. Fromme , J. Waßmuth , D. Wehmeier ,
 Bielefeld University of Applied Sciences, Bielefeld, Germany
The knowledge of the acoustical transfer paths in active noise control systems is very important for the performance of the system. Unfortunately, simulation is challenging since even simple configurations require comprehensive experience in physics and modeling. Two test setups were chosen for basic investigations on modeling, simulation and validation. The first results presented here are ...
R. S. Hallikar , S. Munshi , M. U. Kumari, K. Padmaraju,
 R. V. College of Engineering, Bengaluru, Karnataka, India
 JNTU Kakinada, Kakinada, Andhra Pradesh, India
This paper concentrates on developing a self-contained cochlea whose performance is at par with natural hearing. The Artificial Basilar Membrane (ABM) design is done in such a manner so as to get a performance similar to the natural hearing. Finite element analysis was done with the help of COMSOL Multiphysics software. Two materials, Polyvinylidene fluoride (PVDF) and lead zirconate titanate ( ...
Influence of Thermal Conductivity and Plasma Pressure on Temperature Distribution and Acoustical Eigenfrequencies of High-Intensity Discharge Lamps
J. Schwieger, B. Baumann, M. Wolff, F. Manders, J. Suijker
Heinrich-Blasius-Institute of Physical Technologies, Hamburg University of Applied Sciences, Hamburg, Germany
Philips Lighting, Turnhout, Belgium
High-intensity discharge (HID) lamps are energy-efficient light sources with excellent color qualities. A three-dimensional model of a low-wattage lamp, which includes plasma, electrodes, and burner walls, was developed in COMSOL Multiphysics®. Most parameters appearing in the coupled differential equations of the model, such as viscosity, thermal and electrical conductivity are temperature ...
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, ...
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 ...
J. Soons[1,2], C. Steele, S. Puria
Lab of Biomedical physics, University of Antwerp, Antwerp, Belgium
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 ...