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.


Double-Ridged Horn Antenna

A double-ridged horn antenna is popularly used in anechoic chambers to characterize an antenna under test (AUT), from S-band to Ku-band, due to its reliable performance in a wideband frequency range. This tutorial models a double-ridged horn antenna and computes the voltage standing wave ratio (VSWR), far-field radiation pattern, and antenna directivity. A lumped port is assigned on the ...

Stefan Tube

This example illustrates the use of the Maxwell-Stefan diffusion model available with the Transport of Concentrated Species interface. It models multicomponent gas-phase diffusion in a Stefan tube in 1D. In this case, it is a liquid mixture of acetone and methanol that evaporates into air. The concentration profiles are modeled at steady-state and validated against experimental data by Taylor ...

Probe Tube Microphone

It is often not possible to insert a normal microphone directly into the sound field being measured. The microphone may be too big to fit inside the measured system, such as for in-the-ear measurements for hearing aid fitting. The size of the microphone may also be too large compared to the wavelength, so that it disturbs the acoustic field. In these cases, a probe tube may be attached to the ...

Branch-Line Coupler

A Branch Line Coupler (Quadrature 90° Hybrid) is a four-port network device with a 90° phase difference between two coupled ports. The device can be used for a single antenna Transmitter/Receiver system or an I/Q signal splitter/combiner. The objective of this model is to compute the S-parameters and to observe the matching, isolation, and coupling around the operating frequency.

Viscoelastic Structural Damper

Viscoelastic dampers are frequently used to protect tall structures against vibration. The Viscoelastic Structural Damper application can perform the time-domain and frequency-domain analyses for a typical viscoelastic damper. The purpose of the app is to compute and analyze the important parameters of the damper such as the hysteresis loop and loss and storage moduli for a prescribed material ...

Shape Optimization of a Capacitor Design

This example exemplifies how to optimize the design of a capacitor through optimization. A more detailed description of the phenomenon and the modeling process can be seen in the blog post "[Changing the Dimensions of a Model Using Shape Optimization](https://www.comsol.com/blogs/changing-the-dimensions-of-a-model-using-shape-optimization/)".

Modeling of Wires, Surfaces, and Solids with Boundary-Element-Based Electrostatics

These examples demonstrate using the *Electrostatics, Boundary Elements* interface, introduced in version 5.3 of the COMSOL Multiphysics® software. In the blog post associated with these files, "[How to Create Electrostatics Models with Wires, Surfaces, and Solids](/blogs/how-to-create-electrostatics-models-with-wires-surfaces-and-solids/)", we demonstrate the pros and cons of using the boundary ...

Homogeneous Charge Compression Ignition of Methane

Homogeneous Charge Compression Ignition (HCCI) engines are being considered as an alternative to traditional spark- and compression-ignition engines. As the name implies, a homogeneous fuel/oxidant mixture is auto-ignited by compression with simultaneous combustion occurring throughout the cylinder volume. Combustion temperatures under lean burn operation are relatively low, resulting in low ...

Absorptive Muffler with Shells

This model describes the pressure wave propagation in a muffler for an internal combustion engine. The purpose of the model is to show how to analyze both inductive and resistive damping in pressure acoustics as well as coupling the fluid to the surrounding elastic shell structure of the muffler. Finally, the eigenmodes of a pure structural problem is analyzed and the modes compared to peaks ...

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.