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 ...

### Permanent Magnet

As an example of a magnetostatic problem, consider how to model a horseshoe-shaped permanent magnet. One way is to treat the entire magnet as a ferromagnetic material, where the two end sections are defined as being pre-magnetized in different and opposite directions.

### Heat Sink

This model is intended as a first introduction to simulations of fluid flow and conjugate heat transfer. It shows you how to: Draw an air box around a device in order to model convective cooling in this box, set a total heat flux on a boundary using automatic area computation, and display results in an efficient way using selections in data sets.

### Fluid-Structure Interaction

This model demonstrates how to set up a fluid-structure interaction problem in COMSOL Multiphysics. It illustrates how fluid flow can deform solid structures and how to solve for the flow in a continuously deforming geometry. The Fluid-Structure Interaction (FSI) multiphysics interface combines fluid flow with solid mechanics to capture the interaction between the fluid and the solid structure. ...

### 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 ...

### E-Core Transformer

This is the transient model of a single phase E-core transformer using a Multi-Turn Coil Domain. The model includes the effect of a nonlinear B-H curve in the core and shows how to connect the transformer model to the external circuits using Electric Circuit interface. The simulation is performed for two different cases; the first one with a unity turn ratio and second one with a turn ratio of ...

### 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.