The Application Gallery features COMSOL Multiphysics tutorial and demo app files pertinent to the electrical, mechanical, fluid, and chemical disciplines. You can download ready-to-use tutorial models and demo apps with step-by-step instructions for how to create them yourself. The examples in the gallery serve as a great starting point for your own simulation work.

Use the Quick Search to find tutorials and apps relevant to your area of expertise. Log in or create a COMSOL Access account that is associated with a valid COMSOL license to download the MPH-files.


Thermal Drift in a Microwave Cavity Filter

Microwave filters are used to eliminate unwanted frequency components in the output from microwave transmitters. They are typically inserted between a power amplifier and an antenna. The amplifiers are nonlinear and produce harmonics that must be eliminated with filters that have a rather narrow passband. Due to high power loads but also possibly from harsh environmental conditions (such as a ...

Fast Numerical Modeling of a Conical Horn Lens Antenna

An axisymmetric 3D structure such as a conical horn antenna can be simulated in a fast and efficient way using only its 2D layout. In this model, the antenna radiation and matching characteristics are computed very quickly with respect to the dominant TE mode from the given circular waveguide by simulating the 2D axisymmetric geometry of an 3D antenna structure.

Doppler Shift

We have all noticed the Doppler effect when an ambulance passes by with its sirens blaring. The siren’s pitch suddenly drops the moment the ambulance starts moving away from you. Another effect you can notice is how the siren’s sound is very loud when nearby, but as soon as the ambulance has passed the sound becomes much quieter. This model simulates the acoustic Doppler effect by placing ...

Elastoacoustic Effect in Rail Steel

The elastoacoustic effect is a change in the speed of elastic waves that propagate in a structure undergoing static elastic deformations. The effect is used in many ultrasonic techniques for nondestructive testing of prestressed states within structures. This example studies the elastoacoustic effect in steels typically used in railroad rails. The analysis is based on the Murnaghan hyperelastic ...

Discharge and Self-Discharge of a Lead-Acid Battery

Lead-acid batteries are widely used as starting batteries for various traction applications such as cars and trucks and so forth. The reason for this is the fairly low cost in combination with the performance robustness for a broad range of operating conditions. However, one drawback of this battery type is that the inherent thermodynamics of the battery chemistry causes the battery to self ...

Viscous Catenary

The catenary is the geometrical shape that corresponds to the curve followed by an idealized chain or cable supported at both ends and hanging under its own weight. The viscous catenary problem describes the motion of a cylinder of highly viscous fluid, supported at its ends as it flows under gravity. In the last decade this problem has generated significant theoretical and experimental interest ...

Lorenz Attractor

A Lorenz attractor can be described by a system of ordinary differential equations: the Lorenz system. In the early 1960s, Lorenz discovered the chaotic behavior of this system for certain parameter values and initial conditions. The solution, when plotted as a phase space, resembles the figure eight. This example uses the Dormand-Prince explicit method for solving the ODEs and a Point ...

Energy Conservation with Thermoviscous Acoustics

This small tutorial model studies energy conservation in a small conceptual test setup. The model has an inlet and outlet and a Helmholtz resonator with a very narrow neck. The acoustics in the narrow neck are modeled with Thermoviscous Acoustic for a detailed analysis of the thermal and viscous losses. In order to study and verify energy conservation, the model compares the total dissipated ...

Eigenmodes in a Muffler

In this model, compute the propagating modes in the chamber of an automotive muffler. The geometry is a cross-section of the chamber in the Absorptive Muffler example. The model’s purpose is to study the shape of the propagating modes and to find their cut-off frequencies. As discussed in the documentation for the Absorptive Muffler, some of the modes significantly affect the damping of the ...

Circular Waveguide Filter

A circular waveguide filter is designed using a 2D axisymmetric model. Six annular rings added to the waveguide form circular cavities connected in series, and each cavity cutoff frequency is close to the center frequency of the filter. The simulated S-parameters show a bandpass frequency response.