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.

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 ...

Pervaporation Membrane Module Design with Simulation

J. Boon [1], H. Heuver [2], F. Velterop [2], H. van Veen [1], A. de Groot [1],
[1] ECN, Petten, The Netherlands
[2] Pervatech, Rijssen, The Netherlands

Pervaporation is the selective evaporation of one component in a liquid mixture using a membrane. HybSi pervaporation membranes consist of porous ceramic support tubes with a thin selective layer on the inside or feed side. Modules for 7 and 19 membrane bundles (surface area up to 2.0 m2) are studied in COMSOL Multiphysics® for the absence of pressure drop on the permeate side. With a water flux ...

Simulation of Beverage Refrigeration with Dependence on Container Shape, Material and Orientation

S. Bekemeier[1], L. Fromme[1], A. Genschel[1], K. Kröger[1]
[1]University of Applied Sciences Bielefeld, Department of Engineering Sciences and Mathematics, Bielefeld, Germany

Adequate cooling of beverages is a major issue in planning of several types of events, e.g. poster sessions at conferences. One crucial factor is the time needed to cool beverages from its initial temperature to the desired drinking temperature. We present a way to determine a close approximation for the cooling behavior of three types of commonly used beverage containers using COMSOL ...

Multiphysics Analysis of a Photobioreactor

L. T. Gritter [1], E. Dunlop [2], J. S. Crompton [1], K. C. Koppenhoefer [1]
[1] AltaSim Technologies, Columbus, OH, USA
[2] Pan Pacific Technologies Pty Ltd, Adelaide, South Australia, Australia

Photo-bioreactors generate biomass by providing a controlled environment for the cultivation of algae due to photosynthesis. Algae cultivation can be controlled through the operating parameters and bioreactor environment to allow for high productivity and the use of systems with large surface-to-volume ratios offers maximum efficiency in the use of light compared to alternative batch systems. ...

Uniform Reaction Rates and Optimal Porosity Design for Hydrogen Fuel Cells

J. H. Al-Smail [1]
[1] King Fahd University of Petroleum & Minerals, Dhahran, Saudi Arabia

We develop a porosity-optimization problem to improve the electrochemical reactions taking place in hydrogen fuel cells. We introduce a mathematical model, which involves a system of conservation laws defined in a porous space domain. Our goal is to find the domain's optimal porosity function that can make the oxygen-hydrogen reaction as uniform as possible. The optimal porosity design ...

Kinetics of Proteins in the Blood-Brain Barrier

K. Gandhi [1],
[1] University of California, Riverside, CA, USA

The delivery of chemotherapy for cancer into the central nervous system, in particular the brain, remains a challenge. This results in brain metastases commonly being a cause of death from cancer. Here, we look at the environment of the blood-brain barrier. Then, we explore two proteins (breast cancer resistance protein and p-glycoprotein) that may inhibit the transport of medications (erlotinib ...