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.

Simulation of Chromatographic Band Transport

B. Bunner , A. Kromidas , M. Kele , and U. Neue
Waters Corp, Milford, MA, USA

High-Performance Liquid Chromatography (HPLC) is a standard method in the pharmaceutical industry for the separation and identification of chemical compounds. Modeling of band transport, or band broadening phenomena, can provide tremendous insight into problems of chromatography that are difficult or impossible to measure experimentally. We used COMSOL to analyze two classes of problems in ...

Coupled Heat and Mass Transfer Processes in Enclosed Environments

J.L.Wilson[1], and R. Dwivedi[1]

[1]New Mexico Institute of Mining and Technology, Socorro, New Mexico, USA

Geothermally driven natural convection in enclosures is a ubiquitous process occurring in many physical environments such as caves, mines, etc. We have numerically simulated laminar and turbulent natural convection in isolated air-filled cavities, buried in a more conductive rock mass. We have modeled heat transfer using COMSOL's Convection and Conduction mode. To better understand the ...

Microwave Heating at the Grain Level

S. Lefeuvre[1], and O. Gomonova[2]
[1]Eurl Creawave, Toulouse, France
[2]Siberian State Aerospace University, Krasnoyarsk, Russia

The microwave heating and processing of heterogeneous material is usually simulated using a set of coupled PDE equations in an homogeneous medium. Nowadays it is possible to describe more accurately the process with a suitable description of the heterogeneities that is at the grain level. Many authors work with spheres (circles) to represent the grains but it is difficult to achieve an ...

Analysis of Multiconductor Quasi-TEM Transmission Lines and Multimode Waveguides

S.M. Musa[1], M.N.O. Sadiku[1], and O.D. Momoh[2]
[1]Prairie View A&M University, Prairie View, TX, USA
[2]Indiana University-Purdue University, Fort Wayne, IN, USA

This paper presents an analysis approach of multicondcutor quasi-TEM lines transmission interconnect in a single dielectric region and multimode waveguides using the finite element method (FEM). FEM is especially suitable and effective for the computation of electromagnetic fields in strongly inhomogeneous media. We illustrate that FEM is suitable and effective as other methods for modeling of ...

COMSOL Modelling of a Planar Micro Ion Mobility Spectrometer

R. Cumeras, I. Gràcia, E. Figueras, L. Fonseca, J. Santander, M. Salleras, C. Calaza, N. Sabaté, and C. Cané
Instituto de Microelectrónica de Barcelona, Barcelona, Spain

A micro Planar Ion Mobility Spectrometer (P-FAIMS) has been simulated using multiphysics software. In P-FAIMS target ions are discriminated by the application of the proper separation voltages to the electrodes of the system. Modelling of vapour phase ions of two compounds have been studied for different values of electric field amplitude to gas number density (E/N) ratio: a health risky ...

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 Role of 1D & 2D Asymmetric Diffusion Layers In Rectification Through Ion-Selective Membranes

W. Booth, J. Schiffbauer, and B. Edwards
West Virginia University
Star City, WV

Ion-selective membranes can be used in lab-on-a-chip devices for various portable applications in this field. These devices can be used as concentrators for analytical chemistry and for micro-scale filtration. Here, a binary aqueous electrolyte solution in a microchannel has a potential bias applied across it and it is driven through an ion-selective membrane. Ion concentration gradients form ...

Improved Finite Element Modeling of Heat and Mass Transfers in Single Corn Kernels During Drying

A. J. Kovacs, and M. Nemenyi
University of West Hungary
Institute of Biosystems Engineering
GYMS, Hungary

Our Institute at the West Hungarian University is dealing with modelling of heat physical treatments in agricultural (biological) materials. The essential key in order to gain accurate results is to know the driving forces during heat and mass transfers. In case of mass transfer processes the application of moisture gradient as driving force gives false results. Therefore, we use water ...

3D FEM-analysis of a Micromachined Wind Sensor Based on a Self-heated Thermistor Array

A. Talic[1], S. Cerimovic[2], M. Mutapcic[2], R. Beigelbeck[1], and F. Keplinger[2]
[1]Institute for Integrated Sensor Systems, Austrian Academy of Sciences, Wiener Neustadt, Austria
[2]Institute of Sensor and Actuator Systems, Vienna University of Technology, Vienna, Austria

We present COMSOL-based analyses and design optimizations of a micromachined wind sensor. The sensor relies on eight germanium thermistors embedded in a thin silicon nitride membrane, where two orthogonally arranged ensembles, each consisting of four thermistors, are connected to form a double Wheatstone-bridge. In operation, each bridge is supplied by a constant current and the self-heating of ...

Electro-acoustic Coupling in Nematic Liquid Crystals

G. Rosi[1], L. Teresi[1], A. DiCarlo[1], and F. dell'Isola[2]
[1]LaMS - Università degli Studi Roma Tre, Roma, Italy
[2]Università degli Studi di Roma "La Sapienza", Roma, Italy

Liquid crystals - as all liquids - are generally modelled as incompressible media. In fact, mass-density changes occurring in these mesophases are minuscule and inconsequential in most regimes of interest. However, liquid crystals exhibit also phenomena that call for a more refined theory. In particular, it is experimentally well established that the Fréedericksz transition - i.e., the sudden ...