La Bibliothèque de Modèles présente des modèles construits avec COMSOL Multiphysics pour la simulation d'une très grande variété d'applications, dans les domaines électrique, mécanique, fluidique et chimique. Vous pouvez télécharger ces modèles résolus avec leur documentation détaillée, notamment les instructions de construction pas à pas, et vous en servir comme point de départ de votre travail de simulation. Utilisez l'outil de recherche rapide pour trouver les modèles correspondant à votre domaine d'intérêt, et connectez vous avec votre compte COMSOL Access, associé à une licence COMSOL, afin de télécharger les fichiers modèles.

Radially Polarized Piezoelectric Transducer

This tutorial model shows how a user-defined coordinate system can be used to create any type of directional polarization of a piezoelectric material. Results are shown for the case of radial polarization of a piezoelectric disk. The piezoelectric material is PZT-5H. The example shows a static analysis. Visualization of the cylindrical coordinate system as well as the stress/strain in that ...

Thermal Initial Stresses in a Layered Plate

The thermal stress in a layered plate is studied in this example. A plate consisting of two layers, a coating and a substrate layer is stress and strain free at 800 degrees C. The temperature of the plate is reduced to 150 degrees C and thermal stresses are induced. A third layer, the carrier layer, is added and the thermal stresses in the coating and a substrate layer are added as an initial ...

Piezoresistive Pressure Sensor, Shell

Piezoresistive pressure sensors were some of the first MEMS devices to be commercialized. Compared to capacitive pressure sensors, they are simpler to integrate with electronics, their response is more linear and they are inherently shielded from RF noise. They do, however, usually require more power during operation and the fundamental noise limits of the sensor are higher than their capacitive ...

Pull-in of an RF MEMS Switch

This model analyzes an RF MEMS switch consisting of a thin micromechanical bridge suspended over a dielectric layer. A DC voltage greater than the pull-in voltage is applied across the switch, causing the bridge to collapse onto the dielectric layer with a resulting increase in the capacitance of the device. A penalty based contact force is implemented to model the contact forces as the bridge ...

Thin-Film BAW Composite Resonator

Bulk Acoustic Wave (BAW) resonators can be used as narrow band filters in radio-frequency applications. The chief advantage compared with traditional ceramic electromagnetic resonators is that BAW resonators, thanks to the acoustic wavelength being much smaller than the electromagnetic wavelength, can be made much smaller. In addition to the desired bulk acoustic mode, the resonator structure ...

Piezoelectric Energy Harvester

This model shows how to analyze a simple, cantilever based, piezoelectric energy harvester. A sinusoidal acceleration is applied to the energy harvester and the output power is evaluated as a function of frequency, load impedance and acceleration magnitude.

Thickness Shear Mode Quartz Oscillator

AT cut quartz crystals are widely employed in a range of applications, from oscillators to microbalances. One of the important properties of the AT cut is that the resonant frequency of the crystal is temperature independent to first order. This is desirable in both mass sensing and timing applications. AT cut crystals vibrate in the thickness shear mode—an applied voltage across the faces of ...

Surface Micromachined Accelerometer

This model shows how to simulate a capacitively actuated surface micromachined accelerometer, using the Electromechanics Interface. It is based on a case study from the book Microsystem Design by Stephen D. Senturia (Kluwer Academic Publishers, 5th Edition, 2003, pages 513-525).

Electromagnetic Force Calculation Using Virtual Work and Maxwell Stress Tensor

The model compare the electromagnetic force calculated by *virtual work* and *maxwell stress tensor* methods on the axial magntic bearing. The forces is evaluated by studying the effect of a small displacement on the electromagnetic energy of the system. This is done by using the *Magnetic Fields*, *Deformed Geometry* and *Sensitivity* physics interfaces.

Residual Stress in a Thin Film Resonator - 3D

Surface micromachined thin films are often subject to residual stress. This COMSOL Multiphysics example describes a thin film resonator with straight or folded cantilever beam springs. The resonance frequencies of the resonator are affected by thermal stress. Using folded springs relieves this effect. The example is made up of four models: two thin film resonators with folded cantilever beam ...