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. ...

Wind Evaporation On Wetted Surfaces Under Uncertainty Conditions

J.M. Gozalvez-Zafrilla, M.C. Leon-Hidalgo, J. Lora-Garcia, A. Santafe-Moros, and J.C. Garcia-Diaz
Universidad Politecnica de Valencia, Valencia, Spain

Brine disposal from desalination plants placed in inland areas far from sea is an important problem. Evaporation ponds can be used for reducing the waste to solid state but they require huge amounts of land. Evaporation using arrays of wet surfaces can minimize the land requirements. One characteristic of the methods based on natural evaporation is the uncertainty associated to the influent ...

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 ...

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 ...

Effect of Property Distribution on Flow Behavior in Microfluidic System

M. Motosuke
Tokyo University of Science
Tokyo
Japan

This presentation includes: * A discussion on the role of properties in the micro-world * A simulation of a temperature-dependent property * A numerical model that investigates the effects of temperature and velocity fields This paper is in Japanese.

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 ...

Multiphysics Process Simulation of Static Magnetic Fields in High Power Laser Beam Welding of Aluminum

M. Bachmann[1], V. Avilov[1], A. Gumenyuk[1], M. Rethmeier[1]
[1]BAM Federal Institute for Materials Research and Testing, Berlin, Germany

The article deals with the application of the Hartmann effect in high power laser beam welding of aluminum. The movement of liquid metal in a magnetic field causes electric currents which build a Lorentz force that decelerates the original flow. The numerical model calculates the influence of a steady magnetic field on partial penetration keyhole laser beam welding of aluminum. Three-dimensional ...

Optimized Illumination Directions of Single-Photon Detectors Integrated with Different Plasmonic Structures

M. Csete[1], Á. Sipos[1], A. Szalai[1], G. Szabó[1]
[1]Department of Optics and Quantum Electronics, University of Szeged, Szeged, Hungary

The optimal orientations of different single-photon detector designs were determined by COMSOL software package. Absorption of niobium-nitride (NbN) stripes in two different (p=220 nm, 3p=660 nm) periodic patterns integrated with plasmonic elements was studied. In OC-SNSPDs consisting of ~quarter-photon-wavelength nano-cavity the optimum direction is perpendicular incidence onto NbN stripes in P ...

Singlet Oxygen Modeling of BPD Mediated-PDT Using COMSOL

T.C. Zhu[1], B. Liu[1], X. Liang[1]
[1]University of Pennsylvania, Philadelphia, PA, USA

Singlet oxygen (1O2) is the major cytotoxic agent during photodynamic therapy (PDT). A previously developed model that incorporates the diffusion equation for the light transport in tissue and the macroscopic kinetic equations for the generation of the singlet oxygen, can be used to numerically calculate the distance-dependent reacted 1O2 using finite-element method (FEM). The formula of reacted ...