# Application Gallery

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.

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 ...

### 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.

### 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.

### 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.

### Vacuum Drying

Vacuum drying is a chemical process frequently used in the pharmaceutical and food industries to remove water or an organic solvent from a wet powder. When designing a vacuum drying system, engineers aim to minimize the drying time while maintaining high quality in the product. This model investigates vacuum drying in a Nutsche filter-dryer, which consists of a cylindrical drum filled with wet ...

### 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 ...

### Joule Heating of a Microactuator

This tutorial model of a two-hot-arm thermal actuator couples three different physics phenomena: electric current conduction, heat conduction with heat generation, and structural stresses and strains due to thermal expansion. In this model version, the geometry is parameterized so that the effect of varying the actuator's dimensions can be analyzed.

### Convective Cooling of a Busbar

This is a template MPH-file containing the physics interfaces and the parameterized geometry for the model Electrical Heating in a Busbar.