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 Horizontal Ground Heat Exchangers in Geothermal Heat Pump Systems

A. Chiasson
University of Dayton, Dayton, OH, USA

Geothermal heat pumps use the earth as a heat source and sink via a ground heat exchanger (GHX) that consists of a network of buried heat exchange pipes, which can either be installed in vertical boreholes or in shallow horizontal trenches or excavations. The main goal in GHX design is to determine the minimum length of pipe needed to provide adequate fluid temperatures to heat pumps over their ...

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 ...

Finite Element Analysis of Pipes Considering the Effects of Stress Concentration Due to Dents

S.C. de Oliveira[1], E.P. de Deus[2], and A.M. Mont'Alverne[2]
[1] Funcap/CNPq, CE, Brazil
[2] Universidade Federal do Ceara, Fortaleza, CE, Brazil

This paper presents a numerical analysis of indented pipes based on the Finite Element (FE) within the framework of COMSOL Multiphysics. Numerical models using two-dimensional solid plane strain elements are evaluated. Geometric nonlinear analysis, nonlinear isotropic hardening material and contact were also incorporated into the models. The numerical models are calibrated by using an ...

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 ...

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 ...

Conducting Finite Element Convergence Studies Using COMSOL 4.0

M.K. Gobbert, and D.W. Trott
University of Maryland, Baltimore, MD, USA

We will show how to carry out convergence studies of the FEM error on a sequence of progressively finer meshes in COMSOL Multiphysics on the example of Lagrange elements of varying polynomial degrees, which will also bring out the benefit of using higher order elements. The sample studies will focus on Lagrange elements of degree 1 through 5. For these elements, the convergence order of the ...

Failure Stress Analysis of Fiber Reinforced of Composite Laminates under Uniaxial/Biaxial Loading

Z. Hasan[1], F. Darwish[2], and S. Al-Absi[2]
[1]Texas A&M University, College Station, TX, USA
[2]Jordan University of Science and Technology, Irbid, Jordan

The main objective of the present work is to perform stress analysis on composite laminates under unaxial/biaxial loading to serve as a preliminary data for test verification. A detailed calculation based on the Classical Lamination Theory was performed for a laminate. The material used was carbon/epoxy applying a pure uniaxial load followed by a biaxial load. It was observed that the failure ...

Simulation of Heating Sol-Gel Thin Film By Laser Pulse Train

J. Zhang[1], Y. Mizuyama[1], W. Xiong[2], Y. Zhou [2], and Y. Lu[2]
[1]Panasonic Boston Laboratory, Newton, MA, USA
[2]University of Nebraska, Lincoln, NE, USA

Simulation of laser pulse-train (25ns, 60 kHz and 3000 pulses) heating Sol-Gel thin film using COMSOL Multiphysics software is investigated. The results show two kinds of temperatures formed on film surface by laser pulse-train heating. One is a single pulse induced transient peak-temperature, which is up to ~1635oC on both Si and glass substrates. The other is the accumulated ...

MEMS Comb Drive Gap Reduction Beyond Minimum Feature Size: A Computational Study

N. Osonwanne, and J.V. Clark
Purdue University, West Lafayette, IN, USA

In this paper we present a method to reduce the comb drive gap in micro electro mechanical systems (MEMS) beyond the minimum fabrication feature size. The benefit of reducing the gap space between comb drive fingers is to increase its sensitivity to changes in capacitance due to displacements. The minimum feature size of standard fabrication foundries is 2 microns. To reduce the gap beyond a ...

Virtual Acoustic Prototyping – Practical Applications for Loudspeaker Development

A. Salvatti
JBL Professional, Northridge, CA, USA

The author presents an overview of methods to build virtual prototypes of both horns and loudspeaker drivers which allows a significant reduction in the number of physical prototypes, as well as reduced development time. This paper will present some of the practical results from work the author has performed in the course of designing both transducers and horns using COMSOL Evolution of the ...