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.


Molecular Flow Through a Microcapillary

Computing molecular flows in arbitrary geometries produces complex integral equations that are very difficult to compute analytically. Analytic solutions are, therefore, only available for simple geometries. One of the earliest problems solved was that of gas flow through tubes of arbitrary length, which was first treated correctly by Clausing. Later, the integral expressions he derived were ...

Evanescent Mode Cylindrical Cavity Filter

An evanescent-mode cavity filter is resonant at a frequency lower than its original fundamental mode frequency. Evanescent mode resonance can be realized by creating a discontinuity or reactance inside the cavity. The basic model was modified by the addition of a metal box at either end representing a housing. Inside a dielectric substrate and a microstrip line coupled into the cavity. The ...

Molecular Flow Through an S-Bend

This model computes the transmission probability through an s-bend geometry using both the angular coefficient method available in the Free Molecular Flow interface and a Monte Carlo method using the Mathematical Particle Tracing interface. The computed transmission probability by the two methods is in excellent agreement with less than a 1% difference. This model requires the Particle Tracing ...

Gas Box Designer

This application computes the back pressure in a network of pipes fed by a system of mass flow controllers (MFC). Each MFC supplies a given flow rate to one of the pipes, and can only function correctly if the back pressure remains below 760 Torr. The Pipe Flow Module is used to compute the pressure distribution inside the network of pipes and report whether a given design will meet the back ...

Parameterized Concrete Beam

Reinforced concrete beams are commonly used in modern construction due to their strength and durability. By simulating such beams, engineers can ensure that the resulting structures both perform well and are safe. With simulation apps, engineers of all levels of expertise can analyze and test different designs with ease. The Parameterized Concrete Beam demo app focuses on the structural ...

Frame Fatigue Life

Analyzing fatigue with simulation, rather than running fatigue experiments, is a much quicker way to determine whether a certain design will fail after repeated loading and unloading. This application allows you to evaluate the fatigue life of a frame with a cutout. It is useful for understanding the concept of fatigue and how to build an equivalent app for your own designs. The Frame Fatigue ...

Heterogeneous Model of a Porous Catalyst

A catalyst particle with a hypothetical microstructure is described in detail. The heterogeneous description is approximated in a second model with a homogeneous particle and the results from the two approaches are compared. See: https://www.comsol.se/blogs/modeling-approaches-in-heterogeneous-catalysis/

Electrocoating of a Car Door

This example models electrocoating of paint onto a car door in a time-dependent simulation. The deposited paint is highly resistive which results in lowered local deposition rates for coated areas. A primary current distribution in combination with a film resistance model is used to describe the charge transport in the electrolyte. The model is in 3D and uses an imported CAD geometry.

Induction Motor in 2D - new

This is an example of a model of an induction motor in which the eddy currents are induced in the rotor by the time harmonic currents on the stator windings and the rotation of the rotor. In this example, we analyze the induction motor in 2D using the transient solver in the *Rotating Machinery, Magnetic* interface. We also investigate the motor’s start-up dynamics by coupling the ...

Neutralization of a Proton Beam through a Charge Exchange Cell

Gas cells have several applications in the design of scientific instruments. A gas cell is used to define a high-pressure region within the instrument's main vacuum system. For example, in this application, note we are designing a high-pressure region 100 mm long, with an operating pressure of 1e-3 Torr inside the collision cell and a main vacuum system pressure of 1e-5 Torr. In mass ...