The Application Gallery features COMSOL Multiphysics® tutorial and demo app files pertinent to the electrical, structural, acoustics, fluid, heat, and chemical disciplines. You can use these examples as a starting point for your own simulation work by downloading the tutorial model or demo app file and its accompanying instructions.

Search for tutorials and apps relevant to your area of expertise via the Quick Search feature. To download the MPH-files, log in or create a COMSOL Access account that is associated with a valid COMSOL license. Note that many of the examples featured here can also be accessed via the Application Libraries that are built into the COMSOL Multiphysics® software and available from the File menu.


Vibrating Micromirror with Viscous and Thermal Damping

Micromirrors are used in certain MEMS devices to control optic elements. This model of a vibrating micromirror surrounded by air uses the Thermoacoustic-Shell Interaction user interface to model the fluid-solid interaction, and it thus includes the correct viscous and thermal damping of the mirror from the surrounding air. The resonance frequency of the mirror when under a torquing load is ...

Acoustics of a Pipe System with 3D Bend and Junction

Tutorial that shows how to model the propagation of acoustic waves in large pipe systems by coupling Pipe Acoustics to Pressure Acoustics. The tutorial is set up both in the time domain and in the frequency domain. 1D pipe acoustics is used to model the propagation in the long straight pipe portions. A 3D model of a pipe junction and a pipe bend is coupled to the 1D pipes in order to model ...

Photoacoustic Resonator

This is a model of a simple photoacoustic (or optoacoustic) resonator. A pulsating laser heats a gas causing expansion and contraction and thus creates pressure waves. Such devices are used as sensors for measuring material parameters of the gas inside the resonator. The resonance frequency of the system depends on the gas in the resonator. The model uses the Thermoviscous Acoustic, Frequency ...

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 ...

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.

Noise Radiation by a Compound Gear Train

This example illustrates the modeling of noise radiation from the housing of a gear train. First, a multibody analysis is performed in the time domain to compute the housing vibrations at the specified driver shaft speed. Then, an acoustic analysis is performed at a selected frequency to compute the sound pressure levels in the near, far, and exterior fields using the housing normal ...

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.

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 ...