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.

Secondary Electron Trajectories in Scanning Tunneling Microscopy

H. Cabrera [1], D. A. Zanin [1], L. G. De Pietro [1], A. Vindigni [1], U. Ramsperger [1], D. Pescia [1],
[1] Laboratory for Solid State Physics, Microstructure Research, ETH Zurich, Zurich, Switzerland

The recently developed technique Scanning Tunneling Microscopy in the Field Emission regime (STM FE) is based on the Russell Young's topografiner technology. The set-up is a no contacting device consisting of a sharp tip approached vertically to a conducting surface at variable distances and biased with a small voltage with respect to the surface. The system builds a junction across which ...

Pulsed Electric Field Based Material Removal in Microelectrical Discharge Machining

T. Roy[1],, P. Ranjan[2], , R. Balasubramaniam[2]
[1]Homi Bhabha National Institute, Mumbai, India
[2]Bhabha Atomic Research Centre, Mumbai, India

Micro electrical discharge machining (MEDM), a scaled down version of EDM process, is a micro machining process used to fabricate micro holes and intricate shapes in electrically conductive materials irrespective of its hardness. In this process, an electric spark is generated in the gap between the two electrodes (tool as cathode and workpiece as anode) submerged in dielectric that leads to a ...

微波多模腔金属边界移动对加热的影响研究

于雨田 [1],
[1] 四川大学应用电磁所,成都,中国

本作品通过研究微波炉矩形金属璧的单向移动,实现腔体内电场分布的变化,从而达到调节作用腔体内各点的电场分布的目的。图表1为仿真几何模型示意图,除了腔体内部的小块土豆,其余的腔体材料均为理想导体铜,腔体内为标准大气压下的空气。图表1中300mm*30mm*350mm矩形块的设计是为了更便捷地计算移动后的网格。本次仿真沿x轴正方向向外移动2的外侧面金属壁来实现腔体的移动。端口激励源为TE10模、频率2.45GHz、功率700W、相位为0的微波。图表2为金属壁移动示意图,通过软件的移动网格接口实现移动金属壁的仿真。仿真结果良好,图表3和图表4显示了移动后的输入端口S11值以及土豆加热效果,金属壁移动40mm后,加热物体的加热均匀性提高了14.33%,加热效率提高了38.53%,说明合理地移动微波腔体金属壁可以有效地提高模型的加热均匀性和加热效率。研究结果对工业和科研有着较好的参考意义 ...

Numerical Analysis of Conjugate Heat Transfer in a Combustion Chamber and Firetubes

K. R. Anderson [1], C. Collizi [2],
[1] California State Polytechnic University, Ponoma, CA, USA
[2] Cryoquip, Inc., Murrieta, CA, USA

This paper presents the use of COMSOL's Conjugate Heat Transfer capabilities to model the coupled conduction, convection and surface-to-surface radiation heat transfer in a combustion chamber, firetube heat exchanger device. The paper details the geometry, mesh, governing equations and provides post procession results. The motivation of the study was to compare the COMSOL CFD based results for ...

Model Based Stimulus Experiments to Improve Biological Wastewater Treatment Performance

N. Do [1], M. Stich [1],
[1] Non-linearity and Complexity Research Group, System Analytics Research Institute, School of Engineering and Applied Science, Aston University, Birmingham, United Kingdom

The municipal wastewater treatment in a sustainable context requires a smart technology in which an optimal combination of the ecological status and energy demand can be achieved. The integration of electron conductive materials into a traditionally constructed wetland (CW) has been demonstrated as an emerging strategy for wastewater treatment [1, 2]. By exploiting the electron transfer ...

Modeling of Epithelial Sheet Deformation Under External Force Applied by a Migrating Cell

M. A. Akhmanova [1], A. Ratheesh [1], D. E. Siekhaus [1],
[1] Institute of Science and Technology Austria, Klosterneuburg, Austria

Mechanics of living cells and tissues play a central role in many phenomena, from tissue shape formation (morphogenesis) to migration of cells within tissues. One prominent example is the epithelia – a sheet of cells tightly attached to one another. It provides a physical barrier to separate an organism’s interior from the external environment and serves as a structural support for inner ...

Optimization of an Explosive Mixture Cooling Process Including a Phase Change

J. D. Wheeler [1], P. Namy [1], C. Coulouarn [2], E. Benade [2],
[1] SIMTEC, Grenoble, France
[2] TDA Armements, LA-FERTÉ-SAINT-AUBIN, France

In the scope of improvement of the industrial “ammunition cooling” process, a COMSOL Multiphysics® model is developed to transfer an existing cooling process. A device filled with a liquid explosive mixture is placed in an apparatus which controls the environment temperature. This explosive mixture undergoes a phase change during the cooling and the solidification enthalpy is introduced to the ...

基于 COMSOL 的电容成像传感器仿真研究

李振 [1], 李晨 [1], 符嘉明 [1], 曹松 [1], 王克凡 [1],
[1] 中国石油大学(华东)、青岛、山东、中国

本文针对电容成像传感器仿真分析的难点,以 8 极板电容成像传感器为例,建立了电容成像传感器的三维有限元仿真数学模型,详细介绍了如何使用 COMSOL 软件对电容成像传感器进行三维仿真,后处理结果表明8极板电容成像传感器能检测到有机玻璃内部 7 个不同深度的缺陷,验证了电容成像检测技术的可行性。除此之外还运用 COMSOL 对 8 极板电容成像传感器的电容值进行提取分析,并与实验结果相对比,结果表明两者的检测结果相吻合。此方法方便了电容成像检测技术正问题的研究,为运用COMSOL软件对电容成像传感器的性能分析与参数优化提供了依据。

应用于可穿戴设备的拉伸式压电MEMS能量采集器

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 ...

Finite Element Model of a Magnet Driven Reed Switch

B. LaBarge[1], and E. Gutierrez-Miravete[2]

[1]Gems Sensors and Controls, Plainville, CT, USA
[2]Rensselaer at Hartford, Hartford, CT, USA

A simple proximity sensing circuit is made using magnets actuating reed switches; these switches are wired into a larger circuit that performs auxiliary functions. The success or failure of such systems is a function of their position. A simulation using COMSOL Multiphysics is conducted to study the position of a reed switch relative to a magnet when the switch opens and closes. Ability to ...