Here you will find presentations given at COMSOL Conferences around the globe. The presentations explore the innovative research and products designed by your peers using COMSOL Multiphysics. Research topics span a wide array of industries and application areas, including the electrical, mechanical, fluid, and chemical disciplines. Use the Quick Search to find presentations pertaining to your application area.

Near-Wall Dynamics of Microbubbles in an Acoustical Trap - new

L. Wright[1], G. Memoli[1], P. Jones[2], E. Stride[3]
[1]National Physical Laboratory, Teddington, UK
[2]University College London, London, UK
[3]University of Oxford, Oxford, UK

Understanding the interactions between microbubbles and surfaces is key to the successful deployment of microbubbles in a range of applications. Two important examples are their use as a drug delivery mechanism, and their potential use of acoustically-driven bubbles as microscale sensors. Drug delivery with bubbles involves sonication at high frequency close to a boundary, and sensing with ...

Ultrasound-assisted Microfluidic Devices: Insights and Optimization of Sono-microreactors

F. J. Navarro-Brull [1], P. Poveda [2], J. Ramis [2], R. Gómez [1],
[1] Departament de Química Física, Universidad de Alicante, Alicante, Spain
[2] Departament de Física, Enginyeria de Sistemes i Teoria del Senyal, Universidad de Alicante, Alicante, Spain

Possible drawbacks of microreactors are inefficient reactant mixing due to the predominance of laminar flow and clogging (when solid-forming reactions are performed or solid catalyst suspensions are used). Ultrasound has been successfully implemented not only to prevent these problems but also for its well-known mixing and particle-dispersion effects. Several configurations have been used for ...

Nondestructive Testing of Composites Using Model Based Design

E. Nesvijski[1]
[1]ACOUSTICS@MBD CONSULTANTS, LLC, Westborough, MA, USA

There is a practical interest among composite materials manufacturers to high-speed accurate non-destructive evaluation (NDE) technology for voids inspection when these voids are natural components of such complex structures like resin insulated layer of double-sided copper-clad laminates. Model based design (MBD) of NDE system is one of principal solutions for voids inspection in such ...

安装在有限大障板上的轴对称扬声器特性的近似计算方法

陆晓 [1], 温周斌 [1],
[1] 浙江中科电声研发中心,嘉善,浙江,中国

使用 COMSOL Multiphysics® 仿真轴对称扬声器一般可采用 2D 轴对称模型,但在这种坐标系下无法建立扬声器测量中常用的矩形障板模型,而选择计算安装在无限大障板上扬声器的声特性,其仿真计算结果又与常见的标准障板上的测量结果在中低频段存在较大差异。 为了使无限大障板上的仿真结果与标准障板(或其它有限大障板)上的测量结果相一致,提出一种方法,利用 COMSOL 软件的 Parameter Sweep 功能,通过多次进行 2D 轴对称的电磁场、结构力学和声学三场耦合的扬声器仿真计算及相应后处理,得到安装在有限大障板上的扬声器正前方的声特性。 采用该方法可在较短时间内比较准确地计算得到安装在任意形状的有限大障板上的扬声器的声压级和谐波失真等特性。如图1和图2所示,采用该方法得到的声压级和总谐波失真曲线(红色),与测量结果(黑色)趋势和细节都比较一致。 ...

Optimization of an Acoustic Waveguide for Professional Audio Applications

M. Cobianchi[1] and R. Magalotti[1]
[1] B&C Speakers S.p.a., Bagno a Ripoli, FI, Italia

In modern live sound reinforcement there is a growing use of line sources, obtained through the stacking of many loudspeakers with properly controlled wavefront shape. Thus the use of waveguides is mandatory in order to modify the shape and size of the wavefront exiting from professional compression drivers. With the help of COMSOL Multiphysics®, we have designed a waveguide featuring an ...

Study of an Electroacoustic Absorber

A-S. Moreau[1], H. Lissek[1], and R. Boulandet[1]
[1]EPFL-STI-IEL-LEMA, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland

In this paper, the underlying concept of electroacoustic absorbers is studied with the help of Comsol Multiphysics® Acoustics Module. Among the different ways to obtain variable acoustic properties on an electroacoustic transducer's voicing face, there is the shunting of the transducer's electrical input. With such shunt devices, the acoustic impedance that the transducer's membrane presents ...

Analysis of the Acoustic Response of a Railroad Bridge

K. Koppenhoefer[1], S.Yushanov[1], and M.H. McKenna[2]

[1]AltaSim Technologies, LLC, Columbus, Ohio, USA
[2]U.S. Army Engineering Research and Development Center

Aging infrastructure requires frequent inspections to assess their structural integrity. However, the large amount of existing infrastructure, and the distance between these structures present significant challenges to inspectors. Acoustics-based technologies represent a simple, and relatively inexpensive, technique to monitor the integrity of a structure. To develop these techniques, designers ...

Thermal Analysis of a Piezo-Disk Ultrasound Probe

L. Spicci[1], M. Cati[1]
[1]Esaote, Firenze, Italy

Ultrasound imaging probes are widely used for several types of diagnosis applications. In the present work we focus our attention on a disk-type probe, which is widely used in CW and PW operating conditions. In particular we present a 2D-axial symmetry FEM for the probe, capable to predict both the operative temperature values at different driving signal frequencies, both the heating dynamics. ...

Simplified Finite Element Simulation of a SAW Hydrogen Sensor using COMSOL Multiphysics

N. Krishnan[1], H. Nemade[1,2], and R. Paily[2]
[1]Centre for Nanotechnology, Indian Institute of Technology Guwahati, Assam, India
[2]Department of Electronics and Communication Engineering, Indian Institute of Technology, Assam, India

In this paper, we discuss a simplified finite element method simulation of surface acoustic wave (SAW) delay line hydrogen sensor using COMSOL Multiphysics.  A delay line SAW sensor consists of a transmitting interdigital transducer (IDT) and a receiving IDT separated by a few wavelengths. In this work, the number of degrees of freedom to solve for the SAW delay line sensor model ...

Phonon Tunneling Loss Solver for Micro- and Nanomechanical Resonators

G.D. Cole[1], M. Aspelmeyer[1], and I. Wilson-Rae[2]
[1]University of Vienna, Vienna, Austria
[2]Technical University Munich, Munich, Germany

Micro-and nanoscale mechanical resonators have recently emerged as ubiquitous devices for use in advanced technological applications, for example in mobile communications and inertial sensors, and as novel tools for fundamental scientific endeavors. We report a significant advancement towards understanding and controlling support-induced losses through the demonstration of an efficient numerical ...