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.

Solid Food Pasteurization by means of Ohmic Heating: Influence of Process Parameters

M. Zell[1], D. Cronin[1], D. Morgan[1], F. Marra[2], and J. Lyng[1]
[1]School of Agriculture, Food Science and Veterinary Medicine, Agriculture and Food Science Centre, College of Life Sciences, UCD Dublin, Ireland
[2]Dipartimento di Ingegneria Chimica e Alimentare, Università degli Studi di Salerno, Italy

Pasteurization of solid food undergoing ohmic heating has been analyzed using COMSOL Multiphysics on the basis of a previously validated multiphysics model. The simulation of pasteurization by ohmic heating involves simultaneous solution electrical potential within the food, heat transfer, and the kinetics transport of death of microorganisms. In the model, thermo-physical and electrical ...

A Method for Efficient Calculation of Diffusion and Reactions of Lipophilic Compounds in Complex Cell Geometry

Kristian Dreij[1], Qasim Ali Chaudhry[2], Bengt Jernström[1], Ralf Morgenstern[1], and Michael Hanke[2]
[1]Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
[2]School of Computer Science and Communication, Royal Institute of Technology, Stockholm, Sweden

A general description of effects of toxic compounds in mammalian cells is facing several problems. Firstly, most toxic compounds are hydrophobic and partition phenomena strongly influence their behaviour. Secondly, cells display considerable heterogeneity regarding the presence, activity and distribution of enzymes participating in the metabolism of foreign compounds i.e. bioactivation ...

Numerical Prediction of Particle Dynamics Within a Cytometer. Application to Counting and Sizing by Impendance Measurement

D. Isèbe[1]
[1]HORIBA Medical, Montpellier, France

This paper describes how to numerically tackle the problem of counting and sizing particles by impedance measurement in an orifice–electrode system. The model simulate the particle dynamics submitted to strong hydrodynamic stresses through a microorifice and compute the voltage pulses generated by the modification of the inner dielectric medium. This FSI problem is solved on a moving mesh by ...

基于 DTI 纤维追踪和有限元力学模型的脑损伤轴突纤维损伤研究

李娜 [1], 李江红 [2]
[1] 中南大学湘雅三医院,长沙,湖南,中国
[2] 中车集团南车研究所,株洲,湖南,中国

研究头部损伤机理是对运动撞击中脑损伤进行预测的有效手段。数学模型是分析损伤实验数据、预测人员碰撞损伤程度的唯一方法,但现有的头部损伤有限元模型基于尸体实验数据,且忽略脑组织结构的各向异性。本项目旨在提出并实现一种以损伤生物力学为基础、结合磁共振扫描 DTI 的轴突走向信息的有限元力学模型。提取脑外伤前的弥散张量成像信息,实现深入到轴突水平有限元力学模型的建立,在有限元模拟中采用非线性超弹性力学模型,并植入 NSGAII 最优化方法对有限元模型的材料参数进行优化,从而提高模型的稳定性和计算精度;将计算预测结果与损伤后 DTI 的 FA 值所表现的轴突断裂情况进行验证, 探索活体环境下碰撞损伤中脑轴突的损伤性变化,从而获得脑外伤损伤程度与力学因素之间的关系,为脑外伤损伤程度的预测和脑外伤损伤标准的校正提供精确完整的信息。本项目的研究成果将在汽车碰撞的乘员防护设计上有重要的理论指导价值。 ...

Modeling Enzymatic Pathways in Giant Lipid Vesicles

F. Mavelli [1], E. Altamura [1], P. Stano [2],
[1] University “Aldo Moro”, Chemistry Department, Bari, Italy
[2] Science Department, Roma Tre University, Rome, Italy

Giant vesicles (GVs) are artificial chemical systems largely used as cell models, since they are micrometer-sized closed compartments bounded by a semi-permeable membrane, which in turn is composed by self-assembling amphiphiles. By opportunely engineering the lipid membrane and by entrapping cascade-reaction enzymes inside GVs, it is possible to design micro-sized reactors where metabolic ...

Human Torso Model for Heat Transfer Analysis

X. Xu[1], T. Patel[1], R.W. Hoyt[1]
[1]U.S. Army Institute of Environmental Medicine, Natick, MA, USA

A human torso model was created for heat transfer analysis. The torso was derived from the ‘Virtual Family’ whole-body voxel data from the ITIS Foundation (Zurich, Switzerland). Measurements were taken from the ITIS male along the axial plane at key anatomical landmarks and used to develop geometry in Solidworks. Individual components were created to represent the skin, fat, muscle, and bone ...

Optimizing Performance of Equipment for Thermostimulation of Muscle Tissue using COMSOL Multiphysics

J. Kocbach[1], K. Folgerø[1], L. Mohn[2], O. Brix[3]
[1]Christian Michelsen Research, Bergen, Norway
[2]Luzmon Norway, Bergen, Norway
[3]Michelsen Medical, Bergen, Norway

The design challenge for thermostimulation equipment is to get a combination of high electric field strength and high temperature within the muscle tissue without causing pain or skin burns. In the present work, COMSOL Multiphysics is used to simulate the temperature distribution and electric field distribution within body tissue for varying body composition and varying design parameters of the ...

Microstimulation in The Brain: Does Microdialysis Inuence the Activated Volume of Tissue?

D. Krapohl[1][3], S. Loeffler[2], A. Moser[2], and U.G.Hofmann[1]

[1]Institute for Signalprocessing, University of Luebeck, Lübeck, Germany
[2]Institute for Neurology, University of Luebeck, Lübeck, Germany
[3]Department of Information Technology and Media, Mid Sweden University, Sundsvall, Sweden

Deep Brain Stimulation (DBS) has been established as an effective treatment for Parkinson's disease and other movement disorders. The stimulation is currently administered using tetrode-macroelectrodes that target the Subthalamic Nucleus (STN). This often leads to side effects which bias the surrounding areas, e.g. the speech centre. Targeting a specific brain region can better be achieved with ...

Bayesian Estimation of Tumors in Breasts Using Microwave Imaging

A. Jeremic[1], E. Khosrowshahli[1]
[1]McMaster University, Hamilton, ON, Canada

Although mammography is extremely important diagnostic technique, it suffers from some limitations such as false negative and positive results, using ionizing radiation and patient’s discomfort. Microwave imaging has been recently proposed as an additional medical imaging technique which can potentially overcome some of the shortcomings of the mammography. We believe that the accuracy of ...

Modeling Plant Morphodynamics in Predefined COMSOL Multiphysics® Interface

S. Nikolaev[1], A. Trubuil[2]
[1]Institute of cytology and genetics SB RAS, Novosibirsk, Russia
[2]Institut National de la Recherche Agronomique, Jouy-en-Josas, France

We used a predefined COMSOL Multiphysics® interface to imitate biological growth and shape change (morphodynamics). We found a set of parameters that supply observed morphodynamics for an Arabidopsis embryo during its transition from globular to heart stage.