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.

Hyperbolic Heat Transfer Equation for Radiofrequency Heating: Comparison between Analytical and COMSOL Solutions

V. Romero-García[1], M. Trujillo[2], M.J. Rivera[2], J.A. López Molina[2], and E.J. Berjano[3]
[1]Centro de Tecnologías Físicas Acústica, Universidad Politécnica de Valencia, Valencia, Spain
[2]Dpto. Matemática Aplicada, Instituto Universitario de Matemática Pura y Aplicada, Universidad Politécnica de Valencia, Valencia, Spain
[3]Institute for Research and Innovation on Bioengineering, Universidad Politécnica de Valencia, Valencia, Spain

The Radiofrequency Heating (RFH) is widely employed to heat biological tissue in different surgical procedures. Most models analyze the RFH employing a Parabolic Heat Transfer Equation (PHTE) based on Fourier's theory. The PHTE can be used for problems involving long heating times or low thermal gradients. However, when the problem involves short heating times or extreme thermal gradients it is ...

Measuring and Calculation of Positive Corona Currents Using COMSOL Multiphysics®

M. Quast[1] and N.R. Lalic[1]
[1]Gunytronic GmbH, St Valentin, Germany

The sensor type developed by Gunytronic uses corona discharge for measuring flow rates in exhaust streams of automotives, aircrafts and industrial plants. This paper will present the development of testing equipment used in laboratory for investigating physical relations on corona currents, charged particle transport, the calculation of the collateral electric fields and high potentials. This ...

Fast 2D Simulation of Superconductors: A Multiscale Approach

V.M. Rodriguez-Zermeno[1], M.P. Sørensen[1], N.F. Pedersen[2], N. Mijatovic[2], and A.B. Abrahamsen[3]
[1]DTU Mathematics, Lyngby, Denmark
[2]DTU Electrical Engineering, Lyngby, Denmark
[3]Materials Research Division, Risø, DTU, Roskilde, Denmark

This work presents a method to calculate AC losses in thin conductors such as the commercially available second generation superconducting wires through a multiscale meshing technique. The main idea is to use large aspect ratio elements to accurately simulate thin material layers. For a single thin superconductor, several standard test cases are simulated including transport current, externally ...

Model of Heat and Mass Transfer with Moving Boundary During Roasting of Meat in Convection-Oven

A.H. Feyissa[1], J. Adler-Nissen[1], and K.V. Gernaey[2]
[1]Food Production Engineering, National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
[2]Department of Chemical and Biochemical Engineering, Technical University of Denmark, Kgs. Lyngby, Denmark

A 2D mathematical model of coupled heat and mass transfer describing oven roasting of meat was formulated from first principles. The current formulation of model equations incorporates the effect of shrinkage phenomena and water holding capacity. The model equations are based on conservation of mass and energy. The pressure driven transport of water in meat is expressed using Darcy’s equation. ...

Impedance Spectroscopy and Cell Constant of the Electrodes for Deep Brain Stimulation

E. Vinter[1], S. Petersen[1], J. Gimsa[2], and U. van Rienen[1]

[1]Institute of General Electrical Engineering, University of Rostock, Rostock, Germany
[2]Institute of Biology, University of Rostock, Rostock, Germany

To achieve a deeper understanding of the mechanism of the Deep Brain Stimulation (DBS) scientists use more and more numerical simulations. DBS inhibits overreaching brain activity via electric pulses that send into the brain by electrodes. Different electrode parameters such as geometry, frequency of stimulated impulse or applied voltage have a great influence on the size of the stimulated ...

Static and Dynamic Simulation of an Electromagnetic Valve Actuator Using COMSOL Multiphysics®

R. Wislati[1] and H. Haase[1]
[1]Institut für Grundlagen der Elektrotechnik und Messtechnik, Leibniz Universität Hannover, Hannover, Germany

In this paper an Electromagnetic Solenoid Actuator (EMVA) consisting of an upper and lower electromagnet, a linear moving armature and two preloaded springs is considered as a potential approach in Variable Valve Actuation (VVA) systems for internal combustion engines. The analysis of the upper electromagnet has been performed using Finite Element Method (FEM) simulation. Thereby an axially ...

Numerical Modelling of a Free-Burning Arc in Argon. A Tool for Understanding the Optical Mirage Effect in a TIG Welding Device

J-M. Bauchire[1], E. Langlois-Bertrand[1], and C. de Izarra[1]
[1]GREMI, CNRS, Université d’Orléans, Orléans, France

In this paper, we present the numerical modelling of a free-burning arc and its application to the understanding of optical mirage effect which could occur in a TIG (Tungsten Inert Gas) device used in welding applications.

Multi-Objective Optimization of a Ball Grid Array Using modeFRONTIER® and COMSOL Multiphysics®

H. Strandberg[1], T. Makkonen[2], and J. Leinvuo[2]
[1]ESTECO Nordic AB, Lund, Sweden
[2]VTI Technologies Oy, Vantaa, Finland

Capacitive MEMS (Micro-Electro-Mechanical Systems) accelerometers may be directly soldered to the printed circuit board by an array of solder balls. Differences in the thermal expansion coefficients of the pertinent materials cause deformations of the accelerometer under temperature change. This may cause a relative movement of the sensing masses with respect to the sensing electrodes, resulting ...

The Full-System Approach for Elastohydrodynamic Lubrication

N. Fillot[1], T. Doki-Thonon[1], and W. Habchi[2]
[1]CNRS, INSA, Université de Lyon, Lyon, France
[2]Department of Industrial and Mechanical Engineering, Lebanese American University, Byblos, Lebanon

A ball is in contact with a plane, and a lubricant separates the two surfaces to decrease friction during their relative motion. To avoid wear, the lubricant film thickness should be higher than the surface roughness. The goal of this paper is to show how it is possible to solve efficiently the problem of elastohydrodynamics lubrication with COMSOL Multiphysics®, using a PDE (Partial ...

Simulation Bubble Nucleation and Bubble Growth of a Thermal-Bubble Microejector

Z. Hongwei[1] and A.M. Gué[1]
[1]Laboratoire d’Analyse et d’Architecture de Systèmes, Université de Toulouse, Toulouse, France

The present study investigates simulation model and droplet ejection performance of a thermal-bubble microejector. This model simulates the bubble nucleation and the bubble growth, to predict the droplet ejection process. Specificity, it is achieved by coupling an electric-thermal model and flow model with bubble dynamics equations. The model is validated by comparing prediction results with ...