Modeling and Experimental Verification of the Power Transfer and Thermal Characteristics of Piezoelectric Transformers Subjected to Combined Mechanical and Electrical Loading
S. Tuncdemir, W.M. Bradley
Solid State Ceramics, Williamsport, PA, USA
QorTek, Williamsport, PA, USA
A piezoelectric transformer allows purely mechanical transfer and scaling of electrical energy via simultaneous utilization of both the direct and converse piezoelectric effects. This mechanical energy transfer enables a wide range of functional differences from typical magnetic-based electrical power transformers. Comparing to their electromagnetic counterparts, piezoelectric transformers are ...
ACOUSTICS@MBD CONSULTANTS, LLC, Westborough, MA, USA
There is a practical interest among composite materials manufacturers to high-speed accurate non-destructive evaluation (NDE) technology for voids inspection when these voids are natural components of such complex structures like resin insulated layer of double-sided copper-clad laminates. Model based design (MBD) of NDE system is one of principal solutions for voids inspection in such composites ...
G. Campa, E. Cosatto, S. Camporeale
Politecnico di Bari, Bari, Italy
Ansaldo Energia, Genova, Italy
A hybrid technique based on the use of the FEM and the transfer matrix method is used to identify the frequencies at which thermoacoustic instabilities are expected and the growth rate of the pressure oscillations at the onset of instability. The Helmholtz equation is used to model the combustion chamber and the classical ?-? formulation for the flame model is adopted. The gas turbine combustion ...
M. Weber, T. Kletschkowski, and B. Samtleben
Helmut-Schmidt-University Hamburg, Germany
An inverse finite element method for noise source identification in an aircraft cabin is presented. If all sound sources are located on the boundary of the cabin, the equation system resulting from a matching FE model can be re-sorted in such a way that computation of the unknown boundary data is possible from measurement data taken in the cavity. The method is first validated using a simplified ...
Two-Dimensional FEM Analysis Of Brillouin Gain Spectra In Acoustic Guiding And Acoustic Antiguiding Single Mode Optical Fibers
Y.S. Mamdem, X. Pheron, F.Taillade, Y. Jaouën, R. Gabet, V. Lanticq[1,3], G. Moreau, A. Boukenter, Y. Ouerdane, S. Lesoille, and J. Bertrand
EDF R&D, Chatou, France
ANDRA, Chatenay-Malabry, France
LCPC, Paris, France
Telecom ParisTech, Paris, France
Laboratoire Hubert Curien, Saint-Etienne, France
We present a full modal -analysis of optical and acoustic properties based on two-dimensional finite-element method (2D-FEM) for Brillouin Gain spectrum (BGS) determination in optical fibers with COMSOL. This model enables us to predict precisely the BGS of any kind of silica fiber knowing well the geometry of doping composition. The results of numerical modeling have shown good agreement in ...
Using COMSOL to Support a Cost-Effective, Non-Destructive Evaluation Approach for Predicting Bolt Failure in Highway Bridges
A. Elyea, B. Doubek, G. Hubbard, and D. Ozevin
Department of Civil Engineering
University of Illinois at Chicago
The development of a quantitative nondestructive evaluation method, as an alternative to visual inspection, for inspecting pre-tensioned bolts in fracture critical bridges is presented. In order to understand the ultrasonic behavior of a wide variety of bolt geometries used in bridges, numerical models of nine different bolt geometries were developed. The numerical models included the ...
J. Muraoka, and T. Suzuki
Yamagata Research Institute of Technology
The traveling wave ultrasonic vibration disks for dispersion of particles were designed by using of FEM analysis. The vibration disks are required specific vibration pattern, which contains three nodal lines. The vibration disk thickness was calculated to be matched the resonance frequency of bolted langevin type transducer and the specific vibration pattern. The alignment of the transducer was ...
D. Dimitrov, V. Mihailov, B. Kostov
Technical University of Varna, Varna, Bulgaria
Usually fatigue-life tests of materials are long, time-consuming and expensive. With the development of high power piezoceramic actuators nowadays it is possible to provide at very high cycles 10e10 fatigue tests (VHCF) for reasonable times, at high frequency. The ultrasonic fatigue machine consists of piezoceramic transducer, booster, horn and specimen made of tested material. System works in ...
Simulation of Acoustic Energy Harvesting Using Piezoelectric Plates in a Quarter-Wavelength Straight-Tube Resonator
B. Li, J.H. You
Southern Methodist University, Dallas, TX, USA
An acoustic energy harvesting mechanism at low frequency (~200 Hz) using lead zirconate titanate (PZT) piezoelectric cantilever plates placed inside a quarter-wavelength straight-tube resonator has been studied using COMSOL Multiphysics 4.3 and compared with experimental data. When the tube resonator is excited by an incident wave at its acoustic eigenfrequency, an amplified acoustic resonant ...
Mads Jakob Herring Jensen
Dr., Widex A/S, Denmark
In modern hearing aids, the performance of directional microphone systems is dependent on both the acoustics around thehearing aid and on the specific signal processing algorithms. The sound pressure at the microphone inlets depends on microphone location in the hearing-aid shell, the inlet shape, and on the placement of the hearing aid on the head of the user. In the present work, the ...