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.

Simulations of Microelectrode and Neuron Interfaces Enable Long-Term and High Fidelity Recordings

P. Wijdenes [1], H. Ali [2], N. Syed [3], C. Dalton [2],
[1] Centre for Bioengineering Research and Education, University of Calgary, Calgary, AB, Canada
[2] Department of Electrical and Computer Engineering, Schulich School of Engineering, University of Calgary, Calgary, AB, Canada
[3] Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada

Our inability to record single cell activity with high resolution over a long period of time precludes fundamental understanding of nervous system functions, both under normal and pathological conditions. While the fabrication of current micro- and nano-electrodes has advanced our capabilities to perform long-term recordings, this has been at the expense of signal resolution due to low sealing ...

Influence of Non-Newtonian Blood Viscosity on Wall Pressure in Right Coronary Arteries with Serial Stenoses

B. Liu [1]
[1] Monmouth University, West Long Branch, NJ, USA

Three dimensional mathematical models are developed to simulate the blood flows in patient specific right coronary arteries with two stenoses. Simulations are carried out with various flow parameters under physiological conditions. Both Newtonian and non-Newtonian blood viscosity models are applied in the simulations to examine the influence of non-Newtonian viscosity of blood on the wall ...

CMOS Based Atom Chips for Sensor Applications

Ph. Neuman [1], A. Nemecek [1], C. Koller [2]
[1] Department for Micro-and Nanosystems, University of Applied Sciences Wiener Neustadt, Austria
[2] Department for Micro-and Nanosystems, University of Applied Sciences Wiener Neustadt, Austria, and School of Physics and Astronomy, University of Nottingham, Nottingham, UK

Ultra-cold atomic systems have proven over the last decade to be a excellent platform for the realization of quantum sensors, quantum computation or quantum simulation applications. A special implementation of this technology is the so called atom chip, where the magnetic fields generated by wires on a semiconductor chip will result in elaborated trapping potentials for the atomic ensembles. ...

Near-Field of Resonating Piezoelectric Membrane Used as Ultrasound Transducer

V. Tzanov [1], J. Munoz [1], F. Torres [1], N. Barniol [1],
[1] Universitat Autonoma de Barcelona, Bellaterra, Spain

Micro-machined ultrasound transducers have a wide range of applications. As a sensor or actuator they can be used for measuring fluid speed and direction, to mix and excite particles (sonication), for taking images (ultrasonography), for non-destructive testing and many other purposes in wide variety of fields. For this particular study, a simplified model of micro-machined piezoelectric ...

Electron Trajectories in Scanning Field-Emission Microscopy

H. Cabrera [1],
[1] Swiss Federal Institute of Technology, Zurich, Switzerland

The Scanning Field Emission Microscopy (SFEM) is a novel technology similar to the better known Scanning Tunneling Microscopy (STM). In STM, electrons are exchanged between the outermost atom of a sharp tip and the outermost atom of a target over sub-nanometer distances by means of the quantum mechanical tunnel effect. When the tip is scanned parallel to the surface, the tunneling current can be ...

Green's Function Approach to Efficient 3D Electrostatics of Multi-Scale Problems

C. Roman [1], L. Schmid [1], L. Stolpmann [1], C. Hierold [1],
[1] ETH, Zurich, Switzerland

We present an efficient method to compute efficiently the general solution (Green's Function) of the Poisson Equation in 3D. The method proves its effectiveness when dealing with multi-scale problems in which lower dimensional objects, such as nanotubes or nanowires (1D), are embedded in 3D. Our case-study is a field effect device with a carbon nanotube channel having diameter around 2 nm and ...

Modeling Internal Erosion Processes in Soil Pipes

J. L. Nieber [1], G. V. Wilson [2], G. A. Fox [3],
[1] University of Minnesota, St. Paul, MN, USA
[2] United States Department of Agriculture - Agricultural Research Service National Sedimentation Laboratory, Oxford, MS, USA
[3] North Carolina State University, Raleigh, NC, USA

The erosion of the interior of soil pipes is an important process in the fields of geomechanics and geomorphology. Soil pipes can form in water holding structures like dams and levees, and water flow through these structures becomes concentrated into the soil pipes as they evolve by the process of internal erosion. With time the erosion process will lead to a soil pipe spanning the entire ...


张博 [1],
[1] 平高集团有限公司,平顶山,河南

随着高压直流输电技术的发展,直流气体绝缘金属封闭开关设备(GIS)因其具有占地面积小、可靠性高、维护少等优点已得到越来越多的关注。相比交流GIS,直流GIS绝缘介质表面存在严重的表面电荷积聚问题,导致其沿面闪络特性下降,制约着直流开关设备的工程应用。为了研究直流 GIS 绝缘子绝缘特性,采用 COMSOL 分析软件,基于有限元理论,在考虑绝缘介质阻容模型的基础上,建立了直流 GIS 柱式绝缘子的电场模型,根据此模型,研究了绝缘介质不同材料特性、加压等级在交直流场下的分布规律,并进行了试验验证,为高压开关设备直流绝缘设计优化提供了技术支撑和理论依据。


何启盛 [1],
[1] 上海微系统与信息技术研究所

可穿戴设备是近几年发展最快的电子产品之一,但是目前电池寿命仍然不够长、换电池代价高等问题制约进一步发展。为解决该问题,本文提出一种可拉伸式压电振动能量采集器,通过转化肢体运动的能量直接为设备的供能。该器件由柔性衬底、压电铁磁性悬臂梁以及磁铁组成。当衬底被拉伸,悬臂梁从磁铁上分离,进入高频振动发电状态;当衬底从拉伸状态恢复,悬臂梁被磁铁吸引,再次高频发电。本工作先建立器件 3D 模型,用 COMSOL 结构力学得到的前三阶模态阵型,并和解析计算结果进行对比,阵型函数很相近。采用压电设备和 AC/DC 电路模块进行多物理场耦合:在特征值研究中,分析两次高频振动发电的固有频率和模态;在瞬态研究中,分析器件位移、电压等时域结果,采用对电压求积分的后处理办法计算平均发电效率;还对不同 AC/DC 电阻负载进行参数扫描,找到匹配电阻最大化发电效率。同时采用 AC/DC 无电流磁场模块 ...


安琪 [1], 潘绍丰 [1], 栾兴龙 [1],
[1] 中国地质大学(北京),材料科学与工程学院

生命现象中存在许多复杂的时空调节机制,以便对一些生物活性因子进行合理分配。其中,最为常见的是动态的时空浓度梯度,即随着时间积累,空间各处浓度将不断地发生变化;这一过程对于生物体来说是十分重要的。 本文受生物体系中,扩散过程中快速可逆的超分子结合作用调控浓度梯度的启发,报道水凝胶材料中快速可逆超分子结合调控物质浓度梯度的概念。在接有环糊精的水凝胶基质中,客体分子偶氮苯的扩散受超分子结合的影响,产生与自由扩散不同的浓度梯度分配。 模拟过程运用了 COMSOL Multiphysics 5.2中化学反应工程下的稀物质传递模块。建立一个长 5mm、宽 2mm、高 0.5mm的三维几何体,作为水凝胶基底的模型。然后将 2*0.5mm 截面的某一面设置为具有恒定浓度的边界,其物质为对氨基偶氮苯,作为对氨基偶氮苯溶液与水凝胶的边界;对氨基偶氮苯的两种顺反异构体与 beta ...