G. Campa, and S.M. Camporeale
Politecnico di Bari, Bari, Italy
The Transfer Matrix method in the Acoustics Module of COMSOL Multiphysics is used when the whole system can be represented into a sequence of subsystems that interact only with adjacent subsystems. This method is frequently used in mathematics and, particularly, in acoustics. The application of the present method is really useful, because it permits to break the total system into a network of ...
JBL Professional, Northridge, CA, USA
The author presents an overview of methods to build virtual prototypes of both horns and loudspeaker drivers which allows a significant reduction in the number of physical prototypes, as well as reduced development time. This paper will present some of the practical results from work the author has performed in the course of designing both transducers and horns using COMSOL Evolution of the ...
Simulating Acoustic Combustion Chamber Eigenmodes to Facilitate Combustion Stability in Rocket Engines
R. Kaess , J. Braun ,
 Airbus Safran Launchers, Ottobrunn, Germany
Airbus Safran Launchers is the market leader in Space Launch services. Rocket engines are among the most powerful machines that exist. The core of the rocket engine is the combustion chamber where in the case of liquid propellant rocket engines, fuel and oxidizer are injected, mixed and burnt and where, consequently, the energy release takes place. The hot combustion gases are accelerated in a ...
P. S. K. Mylavarapu, and S. Boddapati
Defence Metallurgical Research Laboratory
Syntactic foams are hollow particle filled composites that have recently emerged as attractive materials for use in advanced structural applications in aerospace and defence industry. Ultrasonic characterization of these foams is performed extensively in order to understand the effect of porosity and particle size on the ultrasonic properties such as longitudinal velocity and attenuation. ...
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 ...
M. Yeoman, V. Sivasailam, A. Tomar
Continuum Blue Ltd., Ystrad Mynach, UK
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 ...
E. Lacatus, G. C. Alecu, A. Tudor, M. A. Sopronyi
Polytechnic University of Bucharest, Bucharest, Romania
Student-Polytechnic University of Bucharest, Bucharest, Romania
INFLPR -National Institute for Laser Plasma and Radiation Physics, Bucharest, Romania
Vibration and music therapies are non-invasive treatments having effective results although their basics are still disputed. By the application of COMSOL Multiphysics® software for modeling and analysis, some of the nonlinear physical phenomena laying on these applications may be clarified. Acoustic environmental stimuli at different intensities are continuously interacting with our bodies, ...
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 ...
K. Chitale , B. Lipkens [1, 2], W. Presz, Jr. ,
 FloDesign Sonics Inc., Wilbraham, MA, USA
 Western New England University, Springfield, MA, USA
Macroscale ultrasonic separation is a new filtration technology, with various applications such as cell clarification, cell therapy, blood-lipid separation, oil-water separation etc. These systems use piezoelectric transducers to create standing waves in fluid-particle mixture. Suspended particles get clustered by action of acoustic radiation forces and are separated out by enhanced gravity ...
Y. Xiong 
 Department of Materials Science and Engineering, Pennsylvania State University - University Park, State College, PA, USA
Phonons underlie the propagation of sound and the transport of heat in materials. With outstanding progress in the design of phononic crystals, it is now feasible to control the acoustic properties of these materials and to endow them with unique acoustic properties. For instance, it has been shown that by decreasing the characteristic dimensions of a phononic crystal, the ability to control ...