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. 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.
While transient analyses are useful for time domain reflectometry (TDR) to handle signal integrity (SI) problems, many RF and microwave examples are addressed using frequency domain simulations generating S-parameters. However, from the frequency domain data it is difficult to identify ... Read More
The principle component of a quadrupole mass spectrometer is the mass filter which is used to filter ions with different charge to mass ratios. The quadrupole mass filter has been well studied over the years, Ref. 1 and the physics and optimal design are well understood. In a real ... Read More
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 ... Read More
A fractal is a mathematical form showing self-repeating patterns. By virtue of its geometrical properties, a fractal structure can generate multiple resonances in RF applications. This antenna model uses a 3rd order Sierpinski triangle and the calculated S-parameters shows good input ... Read More
This tutorial model presents a study showing the transient negative mobility and the negative differential conductivity effects in xenon. The stationary and time dependent Boltzmann equation in the two-term approximation is used to compute the electron energy distribution function. ... Read More
Space charge limited emission is a phenomenon that restricts the current of charged particles that can be released from a surface. As the electron current released by a cathode increases, so does the magnitude of the charge density in the immediate vicinity of the cathode. This ... Read More
The Drift Diffusion interface solves a pair of reaction/advection/diffusion equations, one for the electron density and the other for the mean electron energy. This tutorial example computes the electron number density and mean electron energy in a drift tube. Electrons are released due ... Read More
An evanescent mode cavity filter can be realized by adding a structure inside of the cavity. This structure changes the resonant frequency lower than the dominant mode of the unfilled cavity. A piezo actuator is used to control the size of a small air gap which provides the tunability of ... Read More
This example illustrates the principle of electrochemical polishing. The simplified 2D model geometry consists of two electrodes and an intermediate electrolyte domain The positive electrode has a protrusion, representing a surface defect. The purpose of the model is to examine how this ... Read More
This model solves the Boltzmann equation in two-term approximation for a mixture of nitrogen and oxygen representing a background gas of dry air. Electron transport coefficients and source terms are computed by suitable integration of the electron energy distribution function over ... Read More