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.


Diffraction Patterns

This example resembles the well-known 2-slit interference experiment often demonstrated in schools with water waves or sound. This model mimics the plane-wave excitation with two thin waveguides leading to slits in a screen, and it computes the diffraction pattern on the screen’s other side. This diffraction pattern is clearly visible. The main effect of quantization is that the numerical ...

Pacemaker Electrode

This model illustrates the use of COMSOL Multiphysics for modeling of ionic current distribution problems in electrolytes, in this case in human tissue. The problem is exemplified on a pacemaker electrode, but it can be applied in electrochemical cells like fuel cells, batteries, corrosion protection, or any other process where ionic conduction takes place in the absence of concentration ...

Loaded Spring - Using Global Equations to Satisfy Constraints

Global equations are a way of adding an additional equation to a model. A global equation can be used to describe a load, constraint, material property, or anything else in the model that has a uniquely definable solution. In this example, a structural mechanics model of a spring is augmented by a global equation which solves for the load to achieve a desired spring displacement.

Thin-Film Resistance

In modeling of transport by diffusion or conduction in thin layers, we often encounter large differences in dimensions of the different domains in a model. If the modeled structure is a so-called sandwich structure, we can replace the thinnest geometrical layers with a thin layer approximation, provided that the difference in thickness is very large. This method can be used in many ...

Implementing a Point Source

This model solves the Poisson equation on a unit disk with a point source in the origin. The easiest way to describe a point source in COMSOL Multiphysics is by using an extra weak term. To obtain the weak formulation of the general Poisson equation, we multiply it with a test function u_test and integrate over the domain. The mesh density is dense, close to the origin, so as to resolve the ...

An Integro-Partial Differential Equation

The heat distribution in a hollow pipe, whose ends are held at two different temperatures, is studied. The outside surface is assumed to be thermally isolated and the inner surfaces have radiation boundary conditions. The role of convection in the heat transfer is taken to be negligible. The temperature is assumed to be constant along the thickness of the pipe and rotational symmetry is also ...

Lorenz Attractor

A Lorenz attractor can be described by a system of ordinary differential equations: the Lorenz system. In the early 1960s, Lorenz discovered the chaotic behavior of this system for certain parameter values and initial conditions. The solution, when plotted as a phase space, resembles the figure eight. This example uses the Dormand-Prince explicit method for solving the ODEs and a Point ...

The KdV Equation and Solitons

The Korteweg-de Vries (KdV) equation models water waves. It contrasts sharply to the Burgers equation, because it introduces no dissipation and the waves travel seemingly forever. Solitons have their primary practical application in optical fibers. Specifically, a fiber’s linear dispersion properties level out a wave while the nonlinear properties give a focusing effect. The result is a very ...

Rock Fracture Flow

A potential flow model of fluid flow in a rock fracture uses the so-called Reynolds equation. It shows how to use experimental data interpolated to a function used in the equation.

Process Control Using a PID Controller

This model shows how a flow model can be coupled to a process control mechanism. Controlling application parameters according to other application parameters is important within process engineering. Most control mechanisms use the data at a wall or an outlet to control inlet parameters. More accurate control can occur if you can control inlet parameters due to data found within a component ...