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.

Natural convection in a closed cavity with mass conservation

Only fully compressible flow can guarantee the mass conservation in time in a closed cavity where the temperature increases. This is a simple proof of concept using the "gravity" option available in V5.2A.

Transmission Line Butler Matrix Beamforming Network

A Butler matrix is a passive beamforming feed network. It is a cost-effective feed network for phased array antennas because the circuit can be fabricated in the form of microstrip lines and is a viable solution for performing beam scanning without deploying expensive active devices. This example shows how to design such a circuit using the *Transmission Line* interface. The results show the ...

Electrode Utilization in a Large Format Lithium-Ion Battery Pouch Cell

Large lithium-ion batteries are widely deployed in electric vehicles and for stationary energy storage applications. In the (stacked) pouch battery cell design, all current exits the cell on the cell “tabs”, and as the cell size and power increases, the voltage gradients in the highly conductive metal foil current collectors may come into play, resulting in a non-uniform current distribution and ...

Fundamental Eigenfrequency of a Rotating Blade

High rotational speed in rotating machineries can result in centrifugal forces of considerable magnitude. The forces induced by the rotation give rise to two counteracting effects: stress-stiffening and spin-softening (or centrifugal softening). The former is caused by the stationary stress field created by the centrifugal force and acts to increase the stiffness of the body, and so increase its ...

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.

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 ...

Transverse Modes for a Symmetric Laser Cavity

This model demonstrates how a nonlinear equation system can be setup to solve for the eigenfrequencies of a symmetric laser cavity. The model uses the bidirectional formulation of the Electromagnetic Waves, Beam Envelopes physics interface. The computed eigenfrequencies are verified with values from analytical expressions.

Combining Elastoplastic and Creep Material Models

This model shows how to combine different types of material nonlinearity, such as creep and elastoplasticity. In this specific example you will perform a stress and nonlinear strain analysis on a thick cylinder under a nonproportional loading: an initial temperature increase followed by a fluctuating pressure applied to the internal surface of the cylinder. This load case involves two ...

Thin Low Permittivity Gap Comparison

The thin low permittivity gap boundary condition is meant to approximate a thin layer of material with low relative permittivity compared to its surroundings. This boundary condition is available for electrostatic field modeling. This example compares the thin low permittivity gap boundary condition to a full-fidelity model and discusses the range of applicability of this boundary condition.

Sagnac Interferometer

This is a model of a simple Sagnac interferometer consisting of two mirrors and a beam splitter arranged in a triangle. The entire modeling domain rotates; as a result, the rays propagating in opposite directions in the triangle have different optical path lengths due to the Sagnac effect. This can be used to deduce the angular velocity of the system.