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.

Modeling Thickness Shear Mode Quartz Sensors for Increased Downhole Pressure & Temperature Applications

G.R. Kirikera, W. Patton, and S.M. Behr
Geophysical Research Company LLC, Tulsa, OK, USA

Numerous sensors based on various sensing principles are used to measure pressures and temperatures in wellbores. Of all these sensors, piezoelectric quartz is the most preferred means of sensing pressure and temperature and is probably the only sensor to meet stringent downhole measurement requirements. The sensor consists of a quartz piezoelectric resonator hermetically sealed between two ...

Characterization of an AlGaN/GaN Electrostatically Actuated Cantilever Using the Finite Element Method

N. DeRoller, M. Qazi, J. Liu, and G. Koley
University of South Carolina, Columbia, SC, USA

AlGaN/GaN heterostructures are unique because the 2DEG at the interface is created by the difference in polarization properties of the AlGaN and the GaN layers; not due to intentional doping. In this work, a 3D model of an electrostatically actuated micro cantilever has been developed using COMSOL for characterization using the finite element method (FEM). The microcantilever has AlGaN/GaN HFET ...

Understanding Ferrofluid Spin-Up Flows in Rotating Uniform Magnetic Fields

S. Khushrushahi, and M. Zahn
Massachusetts Institute of Technology, Cambridge, MA, USA

A fully filled sphere of ferrofluid has constant demagnetizing factors in all three Cartesian directions such that when subjected to a uniform external rotating magnetic field the internal field is also uniform, and ultrasound measurements give no observable flow. Non-uniform magnetic fields or a non-uniform distribution of susceptibility are necessary conditions for ferrofluid spin-up flows in ...

COMSOL Multiphysics-Based Exploratory Insulin Secretion Model for Isolated Pancreatic Islets

P. Buchwald
University of Miami, Miami, FL, USA

Insulin released by the beta-cells of pancreatic islets is the main regulator of glucose homeostasis, hence, insulin secretion models are of considerable interest for many possible applications. Building on our previous oxygen consumption and cell viability model for avascular islets of Langerhans, we developed an exploratory insulin secretion model that couples the hormone production rate to ...

Phonon Tunneling Loss Solver for Micro- and Nanomechanical Resonators

G.D. Cole[1], M. Aspelmeyer[1], and I. Wilson-Rae[2]
[1]University of Vienna, Vienna, Austria
[2]Technical University Munich, Munich, Germany

Micro-and nanoscale mechanical resonators have recently emerged as ubiquitous devices for use in advanced technological applications, for example in mobile communications and inertial sensors, and as novel tools for fundamental scientific endeavors. We report a significant advancement towards understanding and controlling support-induced losses through the demonstration of an efficient numerical ...

Dynamic Deformation of Soft Particle in Dual-trap Optical Tweezers

Y. Sheng[1], S. Rancourt-Grenier[1], P. Bareil[1], P. Duval[1], M. Wei[2], A. Chiou[2], and J. Bai
[1]University Laval, Quebec, QC, Canada
[2]National Yang-Ming University, Taipei, Taiwan

A dual-trap optical tweezers is used for deforming the red blood cell (RBC) in suspension and studying its elasticity. The 3D deformation of the cells was computed with the elastic membrane theory. The calculated deformation can fit to experimental data resulting in cell’s elasticity coefficient. The static approach is valid only for small deformation (5-10%). For a large deformation such as ...

The Transient Modeling of Bubble Pinch-Off Using an ALE Moving Mesh

C.J. Forster, and M.K. Smith
Georgia Institute of Technology, Atlanta, GA, USA

The use of an acoustic field to control the boiling process has the potential to increase the overall rate of heat transfer and delay the critical transition to film boiling. This system is being investigated through the development of a model of a single boiling bubble near a flat, heated, horizontal surface in the presence of an acoustic field. The dynamics of the bubble interface is ...

The Dissolution and Transport of Radionuclides From Used Nuclear Fuel in an Underground Repository

Y. Beauregard[1], M. Gobian[2], and F. Garisto[2]
[1]University of Western Ontario, London, ON, Canada
[2]Nuclear Waste Management Organization, Toronto, ON, Canada

In the Canadian concept for a deep geological repository for used nuclear fuel, the used fuel bundles are placed in containers consisting of an inner steel vessel surrounded by a copper shell. The filled containers are placed in excavated tunnels or boreholes and surrounded by a compacted bentonite clay buffer material. In the event of container failure, the rate of migration of radionuclides ...

Modeling PIN Photodiodes

R.W. Pryor
Pryor Knowledge Systems Inc., Bloomfield Hills, MI, USA

This paper presents one approach to the modeling of an abrupt junction PIN photodiode light sensor using COMSOL Multiphysics software and the incorporated SPICE® capability. The current model is built using the capabilities of SPICE in COMSOL Multiphysics 4.0. This model demonstrates the use of SPICE and the AC/DC Module to build a conduction current, rather than an electrostatic, model. This ...

Uncertainty Analysis, Verification and Validation of a Stress Concentration in a Cantilever Beam

S. Kargar, and D. Bardot
University of Alabama, Huntsville, AL, USA

In this paper we compare the results from a bending cantilever beam experiment with the theoretical values and COMSOL finite element simulation results. In the experiment a simple cantilever beam with a hole is loaded at the end. Measurements are recorded by four strain gauges mounted on the beam, three near the hole and one at a location where the nominal stress is equivalent to that of a ...