# Application Gallery

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.

### Solar Panel in Periodic Flow

The coupling of fluid flow and structural mechanics is a challenging problem for several reasons. The fluid flow problem usually requires a specific kind of mesh that is not appropriate for structural mechanics. Additionally, one may want to include geometric features in the structural model that are not significant for the fluid flow model. This model computes the structural stresses and ...

### Cooling of an Injection Mold

This model shows how you can use the Non-Isothermal Pipe Flow interface together with the Heat Transfer in Solids interface to model the cooling of a injection molded polyurethane part for a car steering wheel. The equations describing the cooling channels are fully coupled to the heat transfer equations of the mold and the polyurethane part.

### RF Coil

RF coils are important in numerous applications ranging from wireless technology to MRI scanning equipment. This introductory tutorial model demonstrates how to find the fundamental resonance frequency of an RF coil as well as how to perform a frequency sweep to extract the coil's Q-factor.

### Generator in 2D

In this model, a rotor with permanent magnets and a nonlinear magnetic material rotates within a stator of the same magnetic material. The generated voltage in windings around the stator is calculated as a function of time. COMSOL Multiphysics models the rotation with assemblies and identity pairs. The nonlinearity of the magnetic material is also taken into account using an interpolation ...

### Absorbed Radiation (SAR) in the Human Brain

Scientists use the SAR (specific absorption rate) to determine the amount of radiation that human tissue absorbs. This measurement is especially important for mobile telephones, which radiate close to the brain. The model studies how a human head absorbs a radiated wave from an antenna and the temperature increase that the absorbed radiation causes. The increasing use of wireless equipment has ...

### Equation-Based Modeling in COMSOL Multiphysics

Partial differential equations (PDEs) constitute the mathematical foundation for describing the laws of nature. This presentation provides an introduction to customizing your simulations by developing models directly with PDEs. Learn how to add ordinary differential equations (ODEs) and algebraic equations to your model. Equation-based modeling is a powerful method eliminating the need for ...

### Natural Convection Cooling of a Vacuum Flask

The following example solves a pure conduction and a free-convection problem in which a vacuum flask holding hot coffee dissipates thermal energy. The main interest is to calculate the flasks cooling power; that is, how much heat it loses per unit time. This example treats the natural convection cooling using two approaches: • Using heat transfer coefficients to describe the thermal ...

### Microstrip Patch Antenna

The microstrip patch antenna is used in a wide range of applications since it is easy to design and fabricate. The antenna is attractive due to its low-profile conformal design, relatively low cost and very narrow bandwidth. It is known that the antenna impedance will be higher than an accepted value if fed from the edge, and lower if fed from the center. Therefore, an optimum feed point ...

### Topology Optimization of an MBB Beam

A demonstration of topology optimization using the Structural Mechanics Module and the Optimization Module. Three classical models are shown, the loaded knee, the Michell truss structure, and MBB beam. The optimization method is based on using the SIMPS approach to recast the original combinatorial optimization problem into a continuous optimization problem.

### 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 ...