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.

### Flow Past a Cylinder

The following model examines unsteady, incompressible flow past a long cylinder placed in a channel at right angle to the oncoming fluid. The cylinder is offset somewhat from the center of the flow to make the steady-state symmetrical flow unstable. The simulation time necessary for a periodic flow pattern to appear is difficult to predict. A key predictor is the Reynolds number, which is based ...

### Stresses and Strains in a Wrench

This tutorial demonstrates how to set up a simple static structural analysis. The analysis is exemplified on a combination wrench during the application of torque on a bolt. Despite its simplicity, and the fact that very few engineers would run a structural analysis before trying to turn a bolt, the example provides an excellent example of structural analysis in COMSOL Multiphysics.

### Laser Heating of a Silicon Wafer

A silicon wafer is heated up by a laser that moves radially in and out over time. In addition, the wafer itself is rotated on its stage. The incident heat flux from the laser is modeled as a spatially distributed heat source on the surface. The transient thermal response of the wafer is shown. The peak, average, and minimum temperature during the heating process is computed, as well as the ...

### Heat Transfer by Free Convection

This example describes an array of heating tubes submerged in a vessel with fluid flow entering at the bottom. This is a multiphysics model because it involves fluid dynamics coupled with heat transfer. The pressure and the velocity field are the solution of the Navier-Stokes equations, while the temperature is solved through the heat equation. In this model, the equations are coupled in both ...

### Effective Diffusivity in Porous Materials

Transport through porous structures is usually treated using simplified homogeneous models with effective transport properties. This is in most cases a necessity, since the typical dimensions of the pores and particles making up the porous structure are several orders of magnitude smaller than the size of the domain that is to be modeled. This model introduces the concept of effective ...

### Free Tetrahedral Meshing of a Piston Geometry

This is a tutorial model that demonstrates how to use mesh parameters such as Minimum element size Resolution of curvature Resolution of narrow regions Maximum element growth rate The instructions also detail how to access the mesh statistics and how to create a mesh plot.

### Using Meshing Sequences

COMSOL Multiphysics provides an interactive meshing environment where, with a few mouse clicks, you can easily mesh individual faces or domains. Each meshing operation is added to the meshing sequence. The final mesh is the result of building all the operations in the meshing sequence. This example demonstrates how to use the meshing sequence to create a mesh consisting of different element ...

### Transport and Adsorption

This model demonstrates how to model phenomena defined in different dimensions in a fully coupled manner using COMSOL Multiphysics. Whereas in most cases the reaction rate expression is defined as a function of the concentrations of the reactants and products, in adsorption reactions it is also necessary to model the surface concentrations of the active sites or surface complex. This implies ...

### Steady-State 2D Heat Transfer with Conduction

This example shows a 2D steady-state thermal analysis including convection to a prescribed external (ambient) temperature. It is given as a benchmarking example. The benchmark result for the target location is a temperature of 18.25 C. The COMSOL Multiphysics model, using a default mesh with 556 elements, gives a temperature of 18.28 C. Successive uniform refinements show a temperature of 18.26 ...

### Buoyancy Flow of Free Fluids

This model couples the Navier Stokes equations and the heat transfer equations to examine density driven flow of free fluids. Here the fluid is in a square cavity with a heated wall. The buoyancy force is a Boussinesq term added to the Navier-Stokes equations. The equation is nondimensionalized, so the material coefficients are set up using Rayleigh and Prandtl numbers. The parametric solver ...