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.

Numerical Simulation of Phonon Dispersion Relations for Phononic Crystals

G. Zhu[1], E.M. Dede[1]
[1]Toyota Research Institute of North America, Ann Arbor, MI, USA

In previous work, a two-dimensional (2D) model was carried out to simulate the phononic band structure of a phononic crystal with square lattice structure, but this model did not account for the out-of-plane phonon dispersions [1]. In fact, for 2D films used for coating materials, it is more interesting to understand their cross-plane properties. In this work, the phonon dispersion relation of ...

Poroelastic Models of Stress Diffusion and Fault Re-Activation in Underground Injection

R. Nopper[1], J. Clark[2], C. Miller[1]
[1]DuPont Company, Wilmington, DE, USA
[2]DuPont Company, Beaumont, TX, USA

Stress and failure in the earth have long been observed to couple to hydrogeology. Poroelastic models, introduced by soil scientists, can account for strong two-way coupling between porous crustal rock formations and their pore fluids. Current efforts to provide new energy resources (water injection in EGS, enhanced oil recovery) and to reduce pollution (CO2 sequestration, deepwell disposal) ...

Steps for the Optimization of Pipe and Tubing Extrusion Dies

J.R. Puentes[1], T.A. Osswald[1], S. Schick[2], J. Berg[2]
[1]Polymer Engineering Center, University of Wisconsin, Madison, WI, USA
[2]TEEL Plastics, Baraboo, WI, USA

The extrusion of polyolefin pipes suffers degradation due to mechanical design problems of the extrusion die that is commonly used. This study uses numerical and computational approaches to detect problematic areas in the die geometry. Simulations show that in the conventional die there are areas of stagnation and recirculation of the melt flow, resulting in greater residence times, one of the ...

Modeling Internal Heating of Optoelectronic Devices Using COMSOL

N. Brunner[1][,][2]
[1]Voxtel, Inc, Beaverton, OR, USA
[2]University of Oregon, Eugene, OR, USA

In this paper the heat transfer module in COMSOL is utilized to simulate internal heating of an Avalanche Photodiode due to light-induced current through a resistivity that depends on charge carrier concentrations in the device. Initial tests are done by modeling the heating process on a previously-solved silicon p-n junction as a proof of concept before advancing to a more complicated geometry. ...

Pulsed Eddy Current Probe Development to Detect Inner Layer Cracks Near Ferrous Fasteners Using COMSOL Modeling Software

V. Babbar[1], P. Whalen[1], T. Krause[1]
[1]Department of Physics, Royal Military College of Canada, Kingston, ON, Canada

Surface breaking cracks in conductive structures can be detected by conventional eddy current techniques. However, it is very difficult to detect inner layer defects in multilayered conductive structures either by conventional eddy current or ultrasonic methods. The transient/pulsed eddy current (PEC) technology can potentially overcome these limitations and is being developed for detection of ...

Bayesian Estimation of Tumors in Breasts Using Microwave Imaging

A. Jeremic[1], E. Khosrowshahli[1]
[1]McMaster University, Hamilton, ON, Canada

Although mammography is extremely important diagnostic technique, it suffers from some limitations such as false negative and positive results, using ionizing radiation and patient’s discomfort. Microwave imaging has been recently proposed as an additional medical imaging technique which can potentially overcome some of the shortcomings of the mammography. We believe that the accuracy of ...

Modeling of Chloride Transport in Cracked Concrete: a 3-D Image–Based Microstructure Simulation

Y. Lu[1], E. Garboczi[1], D. Bentz[1]
[1]National Institute of Standards and Technology, Gaithersburg, MD, USA

The prediction of concrete materials service life is not easy, because the complex heterogeneous microstructure and the random nature of concrete materials. Study the presence of cracks in concrete and their effect on coupled reaction and transport are of great interest in civil engineering. Cracks with different widths and depths will reduce the cover thickness and accelerate the migration of ...

Modeling and Prediction of Line Pattern Collapse

D. Bassett[1], M. Carcasi[1], W. Printz[1]
[1]Tokyo Electron America, Austin, TX, USA

In semiconductor manufacturing, effective cleaning of structures with liquid is one of the most important and potentially difficult process steps. It is important because it remains the cheapest and most cost-effective method to remove particles and residues from the structures in order to prevent defects, but can also be difficult because as the structures dry, surface tension forces can cause ...

Modeling Microwave Waveguide Components: The Tuned Stub

R.W. Pryor[1]
[1]Pryor Knowledge Systems, Bloomfield Hills, MI, USA

The waveguide device modeled here specifically demonstrates the exploration of a small, but very important, subset of components of the family of microwave hardware devices designed to facilitate the optimized transfer of power from the generating source to the consuming load. Each of those components is called, in electronics terminology, a Tuned Stub. A stub is a length of transmission line ...

Design Geometry Optimization of Vertical Cracks in Thermal Barrier Coatings from Simulated Thermal and Mechanical Behavior

C. Heveran[1], J. Xu[1], D. Cole[2], S. Basu[1], V. Sarin[1]
[1]Division of Materials Science and Engineering, Boston University, Brookline, MA, USA
[2]Department of Mechanical Engineering, Boston University, Brookline, MA, USA

Turbine blades are coated with thermal barrier coatings (TBCs) to reduce operating temperature. TBCs experience stress from coefficient of thermal expansion mismatch with the bond-coat and substrate. Vertical cracks are thought to offer stress relief, but influence of crack geometry on TBC thermal and mechanical properties is not well understood. A two-dimensional, steady-state model is employed ...