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.

Flow Simulation In A Submerged Membrane Bioreactor At Laboratory Scale

Y.M. Carreño-Martinez, J.M. Gozalvez-Zafrilla, J.A. Mendoza-Roca, and A. Santafé-Moros
Universidad Politecnica de Valencia, Spain

Submerged membrane bioreactor (SMBR) is an efficient technology for wastewater treatment that combines biological process and membrane filtration in one single stage. In the most usual configuration, submerged membrane hollow fibers are set in several planes. Air is introduced from the bottom in order to supply oxygen to the microorganisms but also to reduce fouling over the membrane fibers. ...

Modeling Bacterial Transport and Removal in a Constructed Wetland System

E. Engström, B. Balfors, and R. Thunvik
Royal Institute of Technology, Stockholm, Sweden

In this study we evaluate transport, retention and subsistence of Escherichia coli (E. coli), a common fecal indicator bacteria, in a model (2x1m) of a constructed wetland. Transport occurs in the unsaturated and saturated zone. Inactivation is accounted for as a kinetic first-order process. Retention is assumed to be dominated by solid-air-water interface straining and is modeled with a kinetic ...

The Effect of Electrochemical Micro-Milling by Rotating Magnetic Field

H-Y. Shen[1], H-P. Tsui[1], J-C .Hung[1], S-Y. Lin[2], and B-H. Yan[2]
[1]Metal Industries Research and Development Centre, Taichung, Taiwan
[2]National Central University, Chungli, Taiwan

In this work, the process of micro-channels in electrochemical micro-milling by using rotating magnet assisted helical tool is presented. The results show helical tool and Lorentz force of the rotating magnetic field that enhance the renewal of the electrolyte and machining efficiency. The feed rate can be raised under the magnetic field assisted in terms of experimental results; moreover, the ...

Magnetic Nanoparticles for Novel Granular Spintronic Devices

A. Regtmeier[1], A. Weddemann[2], I. Ennen[3], and A. Hütten[1]
[1]Dept. of Physics, Thin Films and Physics of Nanostructures, Bielefeld University, Bielefeld, Germany
[2]Dept. of Elect. Eng. and Comp. Science, Lab. for Electromagnetic and Electronic Syst., MIT, Cambridge, MA
[3]Institute of Solid State Physics, Vienna University of Technology, Vienna, Austria

Superparamagnetic nanoparticles have a wide range of applications in modern electric devices. Recent developments have identi fied them as components for a new type of magnetoresistance sensor. We propose a model for the numeric evaluation of the sensor properties. Based on the solutions of the Landau-Lifshitz-Gilbert equation for a set of homogeneously magnetized spheres arranged in highly ...

Boundary Element Technique in Petroleum Reservoir Simulation

M. Liu, and G. Zhao
University of Regina
Regina, SK
Canada

Petroleum reservoir simulation is a process of modeling the complex physical phenomena inside a reservoir. This study presents an application of an analytical based numerical scheme so called the Boundary Element Method (DRBEM). It is proven to be able to provide a computationally efficient means of handling single and multiphase flow in a homogeneous medium through the comparison study with ...

Matching 4D Porous Media Fluid Flow GeoPET Data With COMSOL Multiphysics Simulation Results

J. Lippmann-Pipke, J. Kulenkampff, G. Marion, and M. Richter
Helmholtz-Zentrum Dresden
Rossendorf, Institut of Radiochemistry
Research Site Leipzig
Reactive Transport Division
Leipzig, Germany

We apply COMSOL Multiphysics for reproducing our experimental observations of fluid flow and transport processes in geological media. Our experimental GeoEPT-method allows the 4D monitoring of transport processes in geological material on laboratory scale. Explicitly we import “realistic structures” from geologic samples scanned by means of computer tomography (CT) as stl-files into COMSOL ...

High Field Magnetic Diffusion into Nonlinear Ferrimagnetic Materials

J-W. Braxton Bragg[1], J. Dickens[1], A. Neuber[1], and K. Long[2]
[1]Center for Pulsed Power and Power Electronics, Texas Tech University, Lubbock, TX
[2]Dept. of Mathematics, Texas Tech University, Lubbock, TX

Ferrimagnetic based, coaxial nonlinear transmission lines (NLTLs) provide a means to generate sub-nanosecond risetime pulses (from nano-second input pulses) or megawatt level high power microwave oscillations, depending on the geometry, material, and external bias fields. This investigation uses the commercially available, finite element solver COMSOL to provide insight into pulse behavior. ...

A Wide Range MEMS Vacuum Gauge Based on Knudsen’s Forces

V. Sista, and E. Bhattarchaya
Microelectronics and MEMS Lab
Department of Electrical Engineering
Indian Institute of technology Madras
Chennai, India

A MEMS based Knudsen’s pressure gauge working in the range of 1e-5 mbar to 10 mbar is designed and simulated in COMSOL. The working principle is based on Knudsen’s forces that arise when two plates are held at different temperatures and their separation is comparable to the mean free path of the ambient gas molecules. The forces change the separation between the plates and capacitance between ...

Optimization of a High-Temperature High-Pressure Direct Wafer Bonding Process for III-V Semiconductors

R. Martin, J. Kozak, K. Anglin, and W. Goodhue
University of Massachusetts Lowell
Lowell, MA

Many optoelectronic devices utilize a heterojunction of a pair semiconducting materials including high-efficiency MEMS devices, solar cells, LEDs, and VCSELs. One fabrication technique which achieves such a device is direct wafer fusion. To optimize the process, COMSOL Multiphysics 4.0 was used to test various geometric configurations of the fixture. 2D and 3D models were created in order ...

Comsol’s New Thermoviscous Interface and Computationally Efficient Alternative Formulations for FEM

W. R. Kampinga[1], and Y. H. Wijnant[2]
[1]Reden, Hengelo, Netherlands
[2]University of Twente, Enschede, Netherlands

Three efficient alternatives to the model in COMSOL’s thermoacoustics interface are presented. The higher efficiency of these models are explained from theory and are demonstrated by means of two examples.