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.

Nonlinear Acoustics — Modeling of the 1D Westervelt Equation

This model example shows how to model nonlinear propagation of 1D finite-amplitude Acoustic waves in fluids using Acoustics Module of COMSOL Multiphysics. The model is based on the 2nd order Westervelt equation. The one dimensional nonlinear wave equation is solved in the time domain by adding the nonlinear term to the linear equation. The model does not include energy dissipation in order to ...

Acoustic Muffler with Thermoviscous Acoustic Impedance Lumping

This model utilizes the thermoviscous acoustic interface in a sub-model to obtain detailed results for the transfer impedance of a perforated plate (including the thermal and viscous losses). The impedance is in turn used as an internal impedance in a pressure acoustic model of a muffler. The results are compared to classic impedance models and measurements.

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 ...

Shape Optimization of a Tweeter Waveguide

This application illustrates how to use COMSOL’s optimization capabilities to automatically develop novel designs satisfying critical design constraints. The model optimizes a simple speaker geometry. Examples of constraints could include the radius of the loudspeaker or a desired minimum achievable sound-pressure level. To exemplify the optimization capabilities this application studies the ...

Optimizing the Shape of a Horn

A plane-wave mode feeds an axisymmetric horn radiating from an infinite baffle towards an open half space. The radius of the feeding waveguide is assumed to be fixed, as well as the depth of the horn and the size of the hole where the horn is attached to the baffle. By varying the curvature of the initially conical surface of the horn, its directivity and impedance can be changed. This model ...

Generic 711 Coupler—An Occluded Ear-Canal Simulator

This is the model of an occluded ear canal simulator (a generic 711 coupler). Besides certain details the geometry corresponds to the Brüel & Kjær Ear Simulator Type 4157. The real life couplers are used for simulating the acoustics of a standardized human ear canal and can be used for measurements on all sorts of devices. They are widely used in the hearing aid industry but also as ear ...

Lumped Receiver Connected to Test Set-up with a 0.4cc Coupler

In this model a Knowles ED23146 receiver (miniature loudspeaker) is connected to a test set-up consisting of a 50 mm (1 mm diameter) earmold tube and a so-called 0.4-cc coupler. The receiver is modeled using a lumped spice network and connected to the finite element domain at the tube inlet. The response at the measurement microphone in the coupler as well as the electric input impedance to the ...

Acoustic-Structure Interaction and Air Flow in Violins

These models are featured in the blog post [Analyze Violin Tone and Volume with Multiphysics Modeling](http://www.comsol.com/blogs/analyze-violin-tone-and-volume-with-multiphysics-modeling/). One applies acoustic-structure interaction to study how the air mode resonance is affected by the coupled vibrations in the violin body. The other uses a potential flow approximation to find out how the air ...

Axisymmetric Condenser Microphone

This is a model of a condenser microphone with a simple axisymmetric geometry. The model aims to give a precise description of the physical working principles of such a microphone. The condenser microphone is considered to be the microphone with highest quality when performing precise acoustical measurements and with high-fidelity reproduction properties when performing sound recordings. This ...

Apartment Acoustics Analyzed using the Acoustic Diffusion Equation

The sound distribution from a TV in a two-room apartment is computed. The simulation demonstrates the use of the Acoustic Diffusion Equation interface to get a quick and simple estimate of the local sound pressure level. For increased accuracy, an analytical expression for the direct sound is added in the living room.