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.

Prism Coupling of Light in Optical Waveguides

J.T. Andrews, R.R. Kumar, and P.K. Sen
Department of Applied Physics, S G S Institute Technology & Science, Indore, Maharashtra, India

We report the results of simulation showing light coupling in waveguides through prism coupling method. Prism coupling method of light coupling in waveguides is a dominant method adopted by photonic device fabricators. It is necessary to understand the effect various parameters on light coupling in such processes. We used industry standard PDE solver COMSOL Multiphysics to study and analyze the ...

Thermal Properties of Copper Tungsten with Copper Via Composite

J. Ma[1], A. Parker[1], and K. Kuan[2]
[1]Southeastern Louisiana University, Hammond, LA, USA
[2]Torrey Hill Technology LLC, SanDiego, CA, USA

This study focuses on a low-cost composite material based on CuW with Cu via, which functions as a more efficient thermal path for heat conduction. A 50mm X 50mm X 1mm CuW(15/85) speciman consists an array of 30X30 uniformly distributed cylindrical Cu via attaching to a microprocessor generating 100 watts power was studied. By calculating the heat flux coming out of the top and the ...

Evanescent Waves at the Interface Between Ear Canal and Otoacoustic Emission Probe

M. Zebian[1,2], J. Hensel [2], and T. Fedtke[2]
[1]Physikalisch-Technische Bundesanstalt, Braunschweig, Germany
[2]International Graduate School of Metrology, Braunschweig, Germany

Otoacoustic emission (OAE) tests provide an objective examination of the cochlear function. However, the validity of OAE tests is affected negatively by calibration errors. This report sheds light on the evanescent waves arising at the interface between the OAE probe and the ear canal, and analyses the impact of minor eartip modifications on the acoustic length estimation of ear canals, using ...

Comparison of Borehole Heat Exchangers (BHEs): State of the Art vs. Novel Design Approaches

P. Oberdorfer, F. Maier, and E. Holzbecher
Applied Geology
Geoscience Centre
Georg-August-University Göttingen
Göttingen, Germany

The efficiency of borehole heat exchangers (BHEs) for geothermal purposes depends not only on material properties but also on their geometrical design. These days most used design consists of two parallel arranged U-shaped pipes which are embedded in a high-conductive shell filling out the borehole. Another common design is a pipe inside of another pipe, with fluid flowing down inside and up ...

Energetics of Half-Quantum Vortices

K. Roberts[1]
[1]University of Illinois at Urbana-Champaign, Urbana, IL, USA

Magnetic cantilever measurements have detected half-flux states in mesoscopic rings of the layered material Sr2RuO4, adding evidence that superconducting Sr2RuO4 may be described by a p-wave order parameter. A proposal accounting for this behavior has been presented in which the polarization axis of the condensates lies entirely in the plane. In a half-flux state there is a non-zero ...

Microwave Inactivation of Bacteria Under Dynamic Heating Conditions in Solid Media

S. Curet[1], M. Mazen Hamoud-Agha[1]
[1]GEPEA, UMR 6144, CNRS, ONIRIS, Université de Nantes, Nantes, France

In this study, COMSOL®4.2a is used to model a microwave heating process in a TE10 rectangular waveguide. The sample consists of a small cylindrical Ca-alginate gel (D = 8 mm, H = 10 mm) inoculated with bacteria Escherichia Coli K12. The sample is placed along the microwave propagation direction into the waveguide. Maxwell’s equations and heat transfer are coupled to a microbial inactivation ...

Numerical Simulations of Radionuclide Transport through Clay and Confining Units in a Geological Repository using COMSOL

J. Hansmann[1], M. L. Sentis[1], B. J. Graupner[1], A.-K. Leuz[1], C. Belardinelli[2]
[1]Swiss Federal Nuclear Safety Inspectorate (ENSI), Brugg, Switzerland
[2]Kantonsschule Solothurn, Solothurn, Switzerland

Introduction: The sectoral plan that defines the procedure and criteria of site selection for deep geological repositories for all categories of waste (high-level and low- and intermediate-level waste) in Switzerland started in 2008 and will last for about ten years. ENSI (Swiss Nuclear Safety Inspectorate) is in charge of reviewing the proposals and safety assessments for geological ...

Looking for the Origin of Power Laws in Electric Field Assisted Tunneling

H. Cabrera[1], D.A. Zanin[1], L.G. De Pietro[1], A. Vindigni[1], U. Ramsperger[1], D. Pescia[1]
[1]Laboratory for Solid State Physics, ETH Zurich, Zurich, Switzerland

A sharp tip approached perpendicular to a conducting surface at subnanometer distances and biased with a small voltage builds a junction across which electrons can be transferred from the tip apex to the nearest surface atom by direct quantum mechanical tunneling. Such a junction is used e.g. in Scanning Tunneling Microscopy (STM). When the distance d between tip and collector is increased ...

Can we use Aquifers to Monitor Magma Chambers? Using COMSOL Multiphysics® to Investigate Subsurface Strain Changes and Their Effect on Hydrological Systems - new

K. Strehlow[1], J. Gottsmann[1], A. Rust[1]
[1]University of Bristol, Bristol, UK

Groundwater-bearing geological layers respond to and modify the surface expressions of magmatic activity, and they can also become agents of volcanic unrest themselves. Interpretations of unrest signals as groundwater responses to changes in the magmatic system can be found for many volcanoes and include a wide range of phenomena and suggested processes to explain them (e.g., Newhall et al., ...

COMSOL Multiphysics® Models Combined with Experiments to Teach PID Controller Tuning

W. Clark[1]
[1]Chemical Engineering Department, Worcester Polytechnic Institute, Worcester, MA, USA

A laboratory exercise to learn PID controller tuning can be time consuming and taxing on the equipment. A purely equation-based, virtual controller tuning exercise might not seem relevant to real world processes. We have combined a physical process with a COMSOL Multiphysics model to teach the practical aspects of PID controller tuning. Students ran simulated experiments with COMSOL to test ...