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.

Can the Drumhead be Decomposed from Spectra? - An Application for the Chesapeake Bay

K. McIlhany[1], and R. Malek-Madani[2]
[1]Physics Department, United States Naval Academy, Annapolis, MD, USA
[2]Mathematics Department, United States Naval Academy, Annapolis, MD, USA

In 1966, mathematician Mark Kac proposed the question "Can One Hear the Shape of a Drum?" in an article for American Mathematical Monthly. In attempting to resolve the Chesapeake Bay from an eigenfunctional approach, a one-to-one mapping of this famous problem has been identified. The quote above will re-write to "Can One Hear the Shape of a Drum from Multiple Point-Sampled Spectra?". This ...

Earth Pressure as a Boundary Condition to Bridge Piers and Abutments

M. Quinn[1], D. Whitlow[1], O.D.S. Taylor[1], M.H. McKenna[1]
[1] Engineer Resource and Development Center, United States Army Corps of Engineers, Vicksburg, MS, USA

Bridge piers and abutments makeup the bridge substructure and transmit loads from the superstructure to the bridge foundation material (Figure 1). The bridge abutment serves three purposes: to provide vertical support to the bridge superstructure where the bridge ends, to connect the bridge with the approach roadway, and to retain roadway base materials. There are several types of abutment ...

Modeling of Noise Produced by Offshore Wind Turbines with Different Foundations and Effects on the Marine Environment - new

B. Marmo [1], I. Roberts [1]
[1]Xi Engineering Consultants, Edinburgh, Scotland, UK

Vibration produced by offshore wind turbines during their normal operation transmits through the tower into the foundation where it interacts with the surrounding water and is released as noise. The noise produced by offshore wind turbines can be detected by fish and marine mammals and may lead to alteration of their behavior. Given that noise is emitted at the interface between the foundation ...

Towards a Finite Element Calculation of Acoustical Amplitudes in HID Lamps

B. Baumann[1], M. Wolff[1], J. Hirsch[2], P. Antonis[2], S. Bhosle[3], and R. Valdivia Barrientos[4]
[1]Hamburg University of Applied Sciences, Hamburg, Germany
[2]Philips Lighting, Eindhoven, The Netherlands
[3]LAPLACE, Université de Toulouse and CNRS, Toulouse, France
[4]National Institute of Nuclear Research, Salazar, Ocoyoacac, Mexico

High intensity discharge lamps can experience flickering and even destruction, when operated at high frequency alternating current. The cause of these problems has been identified as acoustic resonances inside the lamp’s are tube. Here, a finite element approach for the calculation of the acoustic response function is described. The developed model does not include the plasma dynamics.

Lamb Waves and Dispersion Curves in Plates and It’s Applications in NDE Experiences Using Comsol Multiphysics

P. Gómez, J. P. Fernandez, and P. D. García
Hydro-Geophysics & NDE Modeling Unit
University of Oviedo
Mieres, Spain

In this paper, a model for numerically obtaining lamb wave modes and dispersion curves in plates is presented. It is shown that COMSOL Multiphysics can be employed to simulate the behavior of guided waves in dispersive plates, which is useful for NDE applications. A two dimensional steel plate (4x0.1 meters) is excited with a space-time impact point source. To model the point source, we use ...

Modeling of Ultrasonic Transducers and Ultrasonic Wave Propagation for Commercial Applications Using Finite Elements with Experimental Visualization of Waves for Validation - new

D. R. Andrews[1]
[1]Cambridge Ultrasonics, Over, UK

Finite element (FE) modelling of ultrasonic propagation using COMSOL Multiphysics® simulations can be used to create images of waves. Unfortunately, in time-stepping solutions, it is possible for numerical instabilities to grow large and dominate the solution adversely. Any design of transducer that is based upon poorly-configured FE models is unlikely to perform as expected and will almost ...

FEM Simulation for ‘Pulse-Echo’ Performances of an Ultrasound Imaging Linear Probe

L. Spicci[1]
[1]Esaote SpA, Florence, Italy

Pulse-echo FEM simulation is seldom found in literature for ultrasound imaging array probes, since the complete modeling of such device is extremely complicated. Nevertheless, the 2D FEM described in the present work was successful, thanks to the following design procedure (see figure): Two piezoacoustic models were employed, one for transmission of the pressure wave into the acoustic domain, ...

Analyzing Muffler Performance Using the Transfer Matrix Method 

K. Andersen
Dinex Emission Technology A/S, Middelfart, Denmark

Exhaust noise must meet legislation targets, customer expectations and cost reduction which call for design optimization of the exhaust systems in the design phase. One solution is to use 3 dimensional linear pressure acoustics and calculate the transfer matrix of the muffler. The transfer matrix is the basis for calculating either the insertion loss or transmission loss of a muffler. The 3D ...

Dynamic Structural Modelling of Wind Turbines Using COMSOL Multiphysics

C. Van der Woude, and S. Narasimhan
University of Waterloo, Waterloo, ON, Canada

This paper presents a study of a wind turbine subjected to wind and seismic loading, carried out using COMSOL Multiphysics. The dynamic properties and response of wind turbine structures are of interest, as recent developments in wind energy have led to the design and construction of increasingly large and flexible turbine structures. A typical turbine structure model was created in ...

Dynamics of Rotors on Hydrodynamic Bearings

R. Eling[1]
[1]Mitsubishi Turbocharger & Engine Europe, Almere, The Netherlands

This study presents a rotordynamic analysis of a rotor on hydrodynamic bearings using COMSOL Multiphysics®. In this paper, the complexity of the model is gradually increased. Starting point of the analysis is the modal analysis of the rotor in free-free conditions. A Reynolds model is set up to predict the film pressure distribution under shaft loading. Due to the cross coupling terms of the ...