Ici vous trouverez les présentations issues des Conférences COMSOL à travers le monde. Réalisées par des utilisateurs de COMSOL Multiphysics, ces présentations explorent tous les domaines actuels d'innovation. Les applications couvrent pratiquement tous les secteurs industriels et impliquent des phénomènes électriques, mécaniques, fluidiques et chimiques. Utilisez la recherche rapide pour trouver les présentations les plus intéressantes dans votre domaine d'intérêt.

Time-Domain Model of the Inner Ear to Study Nonlinear Responses

K. Gladine [1], J. Soons [1], J. Dirckx [1]
[1] University of Antwerp, Belgium

The ear doesn’t solely listen but it also speaks. Sounds formed in the inner ear which are measurable in the outer ear are called Otoacoustic emissions (OAEs). Some claim these are produced by the outer hair cells (OHCs), the amplifiers in the inner ear. Our hypothesis is that the OHCs only amplify distortion products (DPs) but do not produce them.

Geometric Multigrid Solver and Experimental Validation in Laser Surface Remelting

M. M. Pariona [1], F. de Oliveira [1],
[1] State University of Ponta Grossa, PR, Brazil

INTRODUCTION The purpose of this work is to verify the effect of Multigrid method on the CPU time for the resolution of the heat transfer model, based on the Finite Element Method (FEM), in order to simulate the laser surface remelting (LSR) of the Al–1.5 wt.% Fe alloy. To accelerate the convergence of Single grid methods, Multigrid method (MG) was employed in order to reduce the CPU time. In ...

Simulation of an AlN Thin Film Resonator for High Sensitivity Mass Sensors

M. Maitra [1], H. B. Nemade [1], S. Kundu [1],
[1] Indian Institute of Technology Guwahati, Guwahati, Assam, India

The objective of this paper is to show the simulation of a piezoelectric thin film device and its application as a sensor. Piezoelectric aluminum nitride thin film clamped at two ends is simulated using COMSOL Multiphysics software. The device consists of the piezoelectric thin film suspended on a cavity etched on a silicon substrate. Two metal electrodes are placed at the two fixed sides of the ...

MEMS Cleanroom Particle Contamination Flow Visualization through Fluid-Structure Interaction Simulation

S. P. Regalla [1], S. R. Vutla [1], A. Shushanth [1], P. K. Pattnaik [1], K. Ramaswamy [1], M. B. Srinivas [1]
[1] Birla Institute of Technology and Science Pilani, Hyderabad Campus, Hyderabad, Telangana, India

This paper reports the simulation of micro-electro-mechanical system (MEMS) cleanroom for the purpose of determining the effect of particulate contaminants on the static stress response of cantilever type MEMS devices, such as high precision MEMS pressure sensor. The contaminant presence has been qualitatively verified through computational fluid dynamic simulation of the clean room in COMSOL ...

基于 ALE 方法的脉冲磁体不可逆电感变化计算

蒋帆 [1], 孙衢骎 [1],
[1] 武汉脉冲强磁场中心,武汉,湖北,中国

目前,脉冲磁体广泛采用导体绕组和加固材料分层交替绕制的工艺(内部层间加固),以提高磁体的整体结构强度。磁体在长期的放电工作过程中,反复经历强电磁力的作用,导体材料(一般为纯铜、铜基合金以及铜基复合材料)在重复的加卸载过程中存在着塑性应变的累积效应,即棘轮效应。导体材料塑性应变的逐渐累积,导致了磁体不可逆电感值的不断增加。因此,磁体的不可逆电感变化可表征磁体内部的整体变形情况,可用于脉冲磁体的疲劳失效预测。 本文基于 COMSOL Multiphysics® 5.1 软件,对脉冲磁体的放电过程建立了电路、电磁场、温度场及结构场的二维轴对称全耦合模型。考虑了放电过程中集肤效应对磁体电阻、电感的影响;在结构场中引入了接触对,采用罚函数法对磁体内部的层间分离机制进行了有效的模拟;利用耦合变量,基于 ALE 方法计算了脉冲磁体在服役过程中 ...

基于声学超材料的近场点声源亚波长分辨率显微成像模拟

韩建宁 [1],
[1] 中北大学,太原,山西,中国

所谓近场声学,是相对于远场声学而言。传统的声学理论,通常只研究远离光源或者远离物体的声场分布,一般统称为远场声学。远场声学在原理上存在着一个远场衍射极限,限制了利用远场光学原理进行显微和其它光学应用时的最小分辨尺寸和最小标记尺寸。而近场声学则研究距离光源或物体一个波长范围内的光场分布。在近场声学研究领域,远场衍射极限被打破,分辨率极限在原理上不再受到任何限制,可以无限地小,从而基于近场声学原理可以提高显微成像与其它光学应用时的光学分辨率。 声学超材料自问世之日起就受到了国内外科学家们的广泛追捧,在很多领域都可以看到其踪迹,以声子晶体为代表的声超材料具有很多天然材料所不具备的声学特性,为声学信号处理带来了很多创新的思路和途径。 声超材料的突出特点在于采用尺寸远小于入射波长的人工结构构建出等效参数,利用等效参数实现“小尺寸结构调控大尺寸波长”的目的。 ...

Influence of Notches in Corners of Casement Windows on Stress Experienced in the Aluminum Profiles under Thermal Load

J. Arfaoui [1], L. Fromme [1]
[1] University of Applied Sciences Bielefeld, Department of Engineering Sciences and Mathematics, Bielefeld, Germany

Modern aluminum casement windows consist of an inner and outer profile made of aluminum, which are separated by an insulating bar made of polyamide (see Figure 1). Due to the low heat conductivity of the plastic material the thermal interaction between the living space and the surrounding is reduced significantly, but thermal expansion of the different materials could cause elastic or even ...

Modeling of a Direct Methanol Fuel Cell

J. Drillet [1],
[1] DECHEMA-Forschungsinstitut, Frankfurt, Germany

This work aims at the modelling of a 5 cm^2 Direct Methanol Fuel Cell (DMFC) with mixed serial/parallel serpentine flow fields in terms of current/voltage behavior. One of the main challenge to overcome consists on lowering the so-called methanol cross over from the anode through the polymer membrane to the cathode that is responsible for mixed-potential formation at the cathode where both ...

Analysis of an Inductive Proximity Sensor

A. Frey [1], I. Kuehne [2], R. Großmann [1], T. Frommelt [1], L. Fromme [3], T. Koch [4],
[1] Augsburg University of Applied Sciences, Augsburg, Bavaria, Germany
[2] Heilbronn University, Heilbronn, Germany
[3] Bielefeld University of Applied Sciences, Bielefeld, Germany
[4] COMSOL Multiphysics GmbH, Göttingen, Germany

Today, 90 percent of automation sensors are binary proximity detectors. Besides capacitive and optical types, inductive proximity sensors are essential for industrial applications. Compared to their mechanical counterparts, they offer almost ideal properties as contact-free and wear-free working principle as well as high switching frequency and precision. Inductive sensors cover a detection ...

Modeling and Characterization of Piezoelectric Structures: From Bulk Material to Thin Film

M. Bavencoffe [1], N. Tembhurnikar [1], B. Negulescu [2], J. Wolfman [2], G. Feuillard [1]
[1] INSA Centre Val de Loire, GREMAN, UMR CNRS 7347, 3 rue de la Chocolaterie, 41034 Blois, France
[2] François Rabelais University, GREMAN, UMR CNRS 7347, Parc de Grandmont, 37200 Tours, France

With the development of micro and nanotechnologies, integrated structures based on piezoelectric thin films are widely investigated and their characterization become a crucial issue for the development of new applications. A laser interferometry is here used to assess the mechanical response in quasistatic regime of a piezoelectric sample. To complete this experimental approach, a numerical ...