Study & Modeling of 'Acoustic Matching Layers' for Ultrasound Imaging Probes Through Pulse-Echo FEM Simulation - new
Esaote SpA, Florence, Italy
Ultrasound Imaging probes are specific devices that require a very detailed design of acoustic impedance match for the stack of layers that form the probe head (1,3). These are typically made of silicone rubber, special epoxy resins, polyurethanes and, of course, piezoelectric materials. The acoustic impedance, measured in Rayls, have to be matched similarly to an electric circuit (2), from a ...
C. R. Pérez , J. J. Santiago-Avilés ,
 Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA, USA
 Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA, USA
Sensorineural hearing loss is the most common sensory deficit in the world, and within this category damage or loss of the primary sensory cells of the inner ear, known as hair cells is the most common cause . Partial hearing loss is addressed by the use of hearing aids, electronic devices that greatly amplify sound directly into the user's ear, but for more severe cases cochlear implants are ...
Danieli Automation S.p.A., Buttrio, UD, Italy
The acoustoelastic effect relates the change in the speed of an acoustic wave travelling in a solid, to the pre-stress of the propagation medium. In this work the possibility of assessing nondestructively the stress status in metal sheets, by using the acoustoelastic effect, is investigated. As the effect turns out to be very small for practical values of applied stress, the proposed technique ...
Utilization of COMSOL Multiphysics® Java API for the Integration of Composite Material Properties Through a Customized User Interface - new
Indian Institute of Technology Madras, Chennai, Tamil Nadu, India
Introduction: Usage of Composite Materials properties is rapidly gaining acceptance in various industries such as aircraft manufacturing, automotive, healthcare, etc. Its main strengths are light weight material, great strength and durability, strength related to weight, corrosion resistance and design flexibility. In the process of modeling and simulation, many a time a user wants to use ...
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 ...
屈治国 , 张秀海 ,
引言 超材料是一类具有天然材料所不具备的特殊性质的材料[1-3]。近年来，有学者开始研究超材料对波的旋转效应，这一研究有着工程应用价值。江雪等设计并实验验证了一种声场旋转器。江雪等进一步研究了声场旋转器整体尺寸大小对其工作带宽的影响及声场旋转器中心处的旋转角度与其结构单元长度的关系。但未见声场旋转器结构单元尺寸对其工作带宽影响的研究。 COMSOL Multiphysics® 的使用 采用 COMSOL Multiphysics® 的声学模块和结构力学模块模拟图1的俯视二维结构，采用完美匹配层以获得更好的模拟结果。 结果 本文模拟了5个声场旋转器在不同频率下的声场，发现随着长方体结构单元长宽比的增加，尽管声场旋转器在低频仍能工作，但可以工作的高频频率是下降的，即声场旋转器的工作带宽是变窄的。为了确定声场旋转器的高频工作截止频率，本文采用二分法确定声场旋转器 ...
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 ...
D. Rubinetti , D. A. Weiss , J. Müller , A. Wahlen ,
 Institute of Thermal and Fluid Engineering, University of Applied Sciences Northwestern Switzerland, Windisch, Switzerland
 Institute of Product and Production Engineering, University of Applied Sciences Northwestern Switzerland, Windisch, Switzerland
Acoustic streaming (AS) describes a physical phenomenon where an oscillating sound emitter induces a steady fluid motion. Metal processing industry applies this treatment for grain morphology adjustments during the solidification of metal. Improvement and further development of this technique focus on numerical modeling to reduce substantial costs for test rigs and field tests. This study ...
Simulation of Pearl-Chain Formation of Microparticles by Acoustic Standing Waves, including Inter-Particle Forces and Collisions
T. Baasch , J. Dual ,
 ETH Zurich, Insitute for Mechanical Systems, Zurich, Switzerland
Acoustic standing waves can be used to manipulate micrometer sized particles, cells and organisms. In most applications these objects are driven towards pressure nodal lines, predominantly by the primary acoustic radiation force. Interestingly, at intermediate particle concentrations, detailed phenomena of line-formation and inter-line repulsion occur. Such phenomena are believed to be caused by ...
A-S.Moreau, H.Lissek, and F. Bongard
Ecole Polytechnique Fédérale de Lausanne, Switzerland
JAST SA, Antenna Systems, Lausanne, Switzerland
In this context, a one-dimensional acoustic transmission line, exhibiting metamaterial properties, is presented. It is composed of an acoustic waveguide, periodically loaded with membranes having the function of series capacitances, as well as transversally connected open channels (denoted stubs) having the function of shunt inductances. A validation of the transmission line design is made ...