Ici vous trouverez les présentations issues des Conférences COMSOL à travers le monde. Réalisées par des utilisateurs de COMSOL Multiphysics, ces présentations explorent tous les domaines actuels d'innovation. Les applications couvrent pratiquement tous les secteurs industriels et impliquent des phénomènes électriques, mécaniques, fluidiques et chimiques. Utilisez la recherche rapide pour trouver les présentations les plus intéressantes dans votre domaine d'intérêt.

Quartz Transducer Modeling for Development of BAW Resonators

L.B.M. Silva[1], E.J.P. Santos[1]
[1]Laboratory for Devices and Nanostructures, Electronics and Systems Department, Universidade Federal de Pernambuco, Recife, PE, Brasil

Transducer optimization is a key aspect for successful development and deployment of advanced sensors, especially when designing 3D structures for harsh environments. For piezoelectric transducers, plate thickness determines the operating frequency of the resonator, which is frequently tuned in the shear thickness vibration mode. Quartz has been the material of choice for the fabrication of ...

Investigation of Mean-Flow Effects on Tubular Combustion Chamber Thermoacoustics Using a Burner Transfer Matrix Approach - new

A. Andreini[1], B. Facchini[1], A. Innocenti[1], D. Pampaloni[1]
[1]University of Florence, Florence, Italy

The paper presents a methodology to account for local mean-flow effects on thermo-acoustic instabilities to improve typical calculations performed under the zero-Mach number assumption. A 3D FEM model of a simplified combustor is solved with COMSOL Multiphysics® Pressure Acoustics interface. The Helmholtz equation is used to model the combustor and the classical k-τ model for the Flame Transfer ...

Acoustic Wave Crack Detection: A First Principles Approach

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

Crack detection is and has been an active field of exploration, both theoretical and applied for a number of years. It is the belief of this author that the concepts presented herein explore a new methodology for the modeling and the detection of cracks and families of cracks in crystalline solids, polycrystalline solids and high viscosity amorphous materials (glasses). In the case of the ...

Acoustic Scattering through a Circular Orifice in Low Mach Number Flow

S. Sack [1], M. Abom [1]
[1] KTH, the Royal Institute of Technology, Stockholm, Sweden

The acoustic scattering through a circular orifice plate in a duct with low Mach number flow (M=0.1) is computed using the Linearized Navier-Stokes physics interface of COMSOL Multiphysics®. The work by Kierkegaard et al. is extended to account for higher order acoustic modes, i.e., behind the cut-on frequency of the first radial duct mode. Orifice flows tend to create a sharp separation zone at ...

RF NEMS Magnetoelectric Sensor Simulation and Demonstration

H. Lin [1], N. Sun [1], N. X. Sun [1],
[1] W.M. Keck Laboratory for Integrated Ferroics, ECE Department, Northeastern University, Boston, MA, USA

RF NEMS Magnetoelectric (ME) Sensor with a ferromagnetic (FeGaB)/ piezoelectric (AlN) thin film heterostructure is simulated, fabricated and measured in this work. To analyze the response of the ME structures, the coupling between the magnetic, elastic and electric field in the two different magnetostrictive and piezoelectric effects should be taken into consideration. Simulations with FEM ...

A FEM Study of Displacement Sensor Based on Magnetostrictive/Piezoelectric Composite Material

Qingwei Liu [1], Hangjie Mo [1]
[1] Shanghai Jiao Tong University, Shanghai, China

This paper studies the application of laminate magnetoelectric (ME) material in displacement sensor. We studied the L-L block composite thanks to designed structure by coupling displacement signal with the displacement potential of ME composite. A nonlinear approximation is adapted to modeling magnetostrictive phase and implemented in COMSOL Multiphysics® software. The simulation results ...

Time-Dependent Study of Pressure Waves Generated by Square Array MEMS Ultrasound Transducers

M. A. G. Suijlen [1], R. J. Woltjer [1],
[1] Novioscan, Nijmegen, Netherlands

For non-imaging wearable ultrasound applications Novioscan is developing piezoelectric MEMS transducers. These transducers consist of a large array of micromechanical silicon membranes with piezoelectrically actuated regions to generate an out-of-plane displacement causing a pressure wave in the adjacent medium. For a typical application of echo sounding in a human body such transducers operate ...

High-Intensity Piezo-Ceramic Ultrasonic Transducer with Mechanical Amplifier and Radiation Plate

A. van Wijhe[1], W. de Jong[1]
[1]Process & Energy, 3mE, TU Delft, The Netherlands

A COMSOL Multiphysics® model was made to design a mechanical amplifier and radiation plate for the emission of high intensity 40.5 kHz ultrasound to air by means of a Langevin type transducer usually applied in cleaning baths for example. In this work, ultrasonic irradiation is aimed at acting on flue gas containing fine particulate matter to realize a shift to higher effective particle sizes as ...

Increasing Heat Transfer in Microchannels with Surface Acoustic Waves - new

S. Berry[1]
[1]Massachusetts Institute of Technology: Lincoln Laboratory, Lexington, MA, USA

In this numerical study, surface acoustic waves (SAWs) are evaluated as a potential disruptive flow technology for enhancing heat transfer in microchannels. Using COMSOL Multiphysics® software, the physics governing acoustics, single-phase-fluid flow and heat transfer are coupled. The results show that acoustic streaming can disrupt the bulk fluid flow, creating rotating vortices within the ...

Orientation of Piezoelectric Crystals and Acoustic Wave Propagation

G. Zhang[1]
[1]Clemson University, Clemson, SC, USA

Surface acoustic wave (SAW) devices are commonly used as wireless filters, resonators, and sensors. The confinement of acoustic energy near the surface of a piezoelectric substrate in a SAW sensor makes it highly sensitive for discerning surface perturbation. As sensors, SAW devices have the potential to provide a high-performance sensing platform with capabilities of remote and high-temperature ...