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.


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 ...

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 ...

Inductive Liquid Metal Pump

Induction pumps are used in high temperature cooling systems. The principle of operation is equivalent to a linear three phase induction motor. The lack of moving parts and the pumped liquid being kept in a hermetically closed system are clear advantages. This model shows how to simulate a generic liquid Na pump.

Voltammetry at a Microdisk Electrode

Voltammetry is modeled at a microelectrode of 10um radius. In this common analytical electrochemistry technique, the potential at a working electrode is swept up and down and the current is recorded. The current-voltage waveform ("voltammogram") gives information about the reactivity and mass transport properties of the analyte. Microelectrodes are popular in electroanalysis because they ...

Modeling of 3-omega Method with Frequency-Domain Analysis of Heat Transfer

This model shows how to define a frequency-domain analysis of heat transfer. The 3-omega method uses the Cahill's equation to approximate the thermal conductivity of a sample from the measured temperature of a metal strip placed on top of it and subject to oscillating heating. The 2D model computes the temperature oscillations of the metal strip and compares the approximated thermal ...

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 ...

Truss Bridge Designer

The Truss Bridge Designer app is an example of how to design a simulation tool for a class of civil engineering structures, in this case a Pratt truss bridge. Such a bridge is characterized by the diagonal beams on each side of the bridge, which all slant down and in toward the center of the span. Because of this design, the diagonal beams are subjected only to tension, while the vertical beams, ...

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/)".

Ion Implanter Evaluator

The Ion Implanter Evaluator app considers the design of an ion implantation system. Ion implantation is used extensively in the semiconductor industry to implant dopants into wafers. Within an ion implanter, ions generated within an ion source are accelerated by an electric field to achieve the desired implant energy. Ions of the correct charge state are selected by means of a separation ...

Small Signal Analysis of a MOSFET

This model shows how to compute the AC characteristics of a MOSFET. Both the output conductance and the transconductance are computed as a function of the drain current.