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.

Low Pt Cathodes for High Performance PEMFCs: Modeling and Experiments

F. Daouda[1], J. Hamelin[1], P. Benard[1], S. Kumar Natarajan [1]
[1]Insitut de recherche sur l'hydrogène, Université du Québec à Trois-Rivières, Trois-Rivières, Québec, Canada

We present a novel multi-layered electrode fabrication technique for polymer electrolyte membrane fuel cells (PEMFCs). This method consists of alternate layers of Pt deposition (0.05 mg/cm²) by sputtering on the painted multi-walled carbon-Nafion layer (CNL) with larger concentration of catalyst particles closer to the membrane. Parametric models were developed and validated by experimental ...

BHE Field Design by Superposition of Effects in Space and Time

S. Lazzari[1], E. Zanchini[1]
[1]DIENCA - University of Bologna, Bologna, Italy

A design method for BHE fields in the absence of groundwater flow is presented, based on the superposition of effects. The effects of any periodic heat load with a period of one year can be obtained by a weighted sum of the effects of a monthly unit step heat load, properly displaced in time. The interference among BHEs is evaluated by the superposition of effects in space. The result of the ...

Kinetic Investigation of a Mechanism for Generating Microstructures on Polycrystalline Substrates Using an Electroplating Process

T. Soares[1], H. Mozaffari[2], H. Reinecke[1]
[1]Universität Freiburg, Freiburg im Breisgau, BW, Germany
[2]Hochschule Furtwangen, Tuttlingen, BW, Germany

The purpose of this study is to understand the growth mechanism of copper (Cu) films on a Cu-Zn system substrate with a pre-defined pattern. The pattern was defined by conducting a selective etching process on a two-phase polycrystalline substrate. As a result of this process, there were etched regions correspondent to beta-phase crystals and quasi non-etched regions that belong to alpha-phase ...

Numerical and Experimental Investigation of Natural Convection Flow of (Sub-) and (Super-) Critical CO2 in Aqueous Phase

R. Khosrokhavar[1], G. Elsinga[1], R. Farajzadeh[2], H. Bruining[1]
[1]Delft University of Technology, Delft, The Netherland
[2]Shell International Global Solutions, Amsterdam, The Netherland

Optimal storage of carbon dioxide (CO2) in aquifers requires dissolution in the aqueous phase. Transfer of CO2 from the gas phase to the aqueous phase or oil phase would be slow if it were only driven by diffusion. Dissolution of CO2 in brine (oil) forms a mixture that is denser than the original brine. This causes a local density increase, which induces natural convection currents accelerating ...

Methodology for Calculation Scattering Parameters in a Transmission-Line Transducer

E.J.P. Santos[1], L.B.M. Silva[1]
[1]Laboratory for Devices and Nanostructures, Departamento de Eletrônica e Sistemas, Universidade Federal de Pernambuco, Várzea, Recife, PE, Brasil

Transmission-line transducers are used for the measurement of absorption and reflection of different materials, such as: liquids, granular medium, and ground. A simplified methodology for calculation of scattering parameters of such transducers is presented. The transducer cell is partitioned at each interface and the partial scattering equations are calculated, considering two interfaces at a ...

Microfluidics based Worm Sorter

Koduri V.V.N.R.M Manohar Prasad[1], John Yan[2], Andrew A.Bettiol[2], K.C James Raju[1]
[1]University of Hyderabad, Hyderabad, Andhra Pradesh, India
[2]National University of Singapore, Singapore

The nematode Caenorhabditis elegans is a widely adopted model organism for studying various neurobiological processes at the molecular and cellular level in vivo. With a small, flexible, and continuously moving body, the manipulation of C.elegans becomes a challenging task. A lab-on-a-chip (LOC),is a device that integrates one or several laboratory functions on a single chip of only mm to a few ...

Design of a MEMS Resonator for a Centre Frequency Greater than 26.35 MHz and Temperature Coefficient Frequency Less than 0.5 ppm

S.Manikandan[1], R.Radeep krishna[1]
[1]Kalasalingam University, Department of ECE, Srivilliputtur ,Krishnan koil, Tamil Nadu, India

The variability of the design parameters caused by material properties like thermal conductivity is the major challenge in Micro Electromechanical System (MEMS). In resonator design the basic problem is that the frequency changes with temperature variation and quantitative explanation with respect to this varies. The change can be attributed to the stability in terms of frequency drift in parts ...

Optimization of a Rotor Shape for Spherical Actuator with Magnetically Levitating Rotor to Match Octupole Field Distribution

M. Sidz[1], R. Wawrzaszek[1], L. Rossini[2], A. Boletis[3], S. Mingard[3], K. Seweryn[1], E. Onillon[2], M. Strumik[1]
[1]Space Research Centre of PAS, Warsaw, Poland
[2]CSEM Centre Suisse d’Electronique et de Microtechnique SA, Neuchâtel, Switzerland
[3]Maxon Motor AG, Sachseln, Switzerland

The use of a reaction sphere as an actuator used by satellite Attitude Control System was proposed over twenty years ago. In principle this concept assumes the use of a single reaction sphere which can be accelerated in any direction instead of a set of reaction wheels. The solution discussed in this work has been proposed and patented by CSEM company. Contrary to conventional ball bearing ...

Modeling Charge/Discharge Heat Generation of Li-ion Cells and Experimental Verification of Temperature Distribution

Tatsuya YAMAUE[1]
[1] Kobelco Research Institute, Inc., Kobe, Hyogo, Japan

Modeling the heat generation and the heat transfer of the electrode of lithium-ion battery are introduced. There are several models, such as an homogeneous heating model and a model considering the current and reaction distribution of electrode. Generally, electrodes have large area and the calculation load of the model becomes high. Therefore, some approximated models are required to analyze ...

Assessment of the SNR, G-Factor and Relative B1- Fields of Medical Radiofrequency Arrays - new

G. Cook[1], F. Robb[2], M. Graves[1], D. Lomas[1]
[1]Department of Radiology, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK
[2]GE Healthcare Coils, Aurora, OH, USA

MRI relies upon a static magnetic field which creates a net magnetic moment from proton spins and radio-frequency fields are generated to excite this magnetic moment into a perpendicular plane, where it can be detected through the use of an array of conductive loops. The optimal size,shape and layout of these elements has been widely discussed in literature since the phased array's conception ...