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.

Muffler with Perforates

Reflective mufflers are best suited for the low frequency range where only plane waves can propagate in the system, while dissipative mufflers with fibers are efficient in the mid-to-high frequency range. Dissipative mufflers based on flow losses, on the other hand, work also at low frequencies. A typical automotive exhaust system is a hybrid construction consisting of a combination of ...

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 ...

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 Thermoacoustic Impedance Lumping

This model utilizes the thermoacoustic 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.

Acoustic Cloaking

Two articles in the New Journal of Physics describe how to derive necessary conditions on an anisotropic density tensor to create a perfect acoustic cloak in 2D, and show how this material can be realized in practice as a layered shell with isotropic properties in each layer. These two example files illustrate simplest possible implementations using both anisotropic density and the layered ...

Hollow Cylinder

Fluid acoustics coupled to structural objects, such as membranes or plates, represents an important application area in many engineering fields. Some examples are: • Loudspeakers • Acoustic sensors • Nondestructive impedance testing • Medical ultrasound diagnostics This model provides a general demonstration of an acoustic fluid phenomenon in 3D coupled to a solid object. In this ...

Vibrations of a Disk Backed by an Air-Filled Cylinder

The vibration modes of a thin or thick circular disc are well known, and it is possible to compute the corresponding eigenfrequencies to arbitrary precision from a series solution. The same is true for the acoustic modes of an air-filled cylinder with perfectly rigid walls. A more interesting question to ask is: What happens if the cylinder is sealed in one end not by a rigid wall but by a thin ...

Organ Pipe Design

The Organ Pipe Designer allows you to study the design of an organ pipe and then play the sound and pitch of the changed design in a user-friendly app. The pipe sound includes the effects of different harmonics with different amplitudes. The organ pipe is modeled using the Pipe Acoustics, Frequency Domain interface in COMSOL Multiphysics. The simulation app allows you to analyze how the first ...

Piezoelectric Tonpilz Transducer with a Prestressed Bolt

A tonpilz transducer is used for relatively low frequency, high power sound emission. It is one of the popular transducer configurations for SONAR applications. The transducer consists of piezoceramic rings stacked between a head mass and a tail mass which are connected by a central bolt. This example shows how to incorporate the effect of a pre-tension in the bolt. The bolt geometry is ...

Lumped Loudspeaker Driver

This is a model of a moving-coil loudspeaker where a lumped parameter analogy represents the behavior of the electrical and mechanical speaker components. The Thiele-Small parameters (small-signal parameters) serve as input to the lumped model, which is represented by an Electric Circuit physics. The lumped model is coupled to a 2D axisymmetric Pressure Acoustics model describing the ...