# 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.

### Frequency Selective Surface, Periodic Complementary Split Ring Resonator

Frequency selective surfaces (FSS) are periodic structures with a bandpass or a bandstop frequency response. This model shows that only signals around the center frequency can pass through the periodic complementary split ring resonator layer.

### Magnetic Field of a Helmholtz Coil

A Helmholtz coil is a parallel pair of identical circular coils spaced one radius apart and wound so that the current flows through both coils in the same direction. This winding results in a uniform magnetic field between the coils with the primary component parallel to the axes of the two coils. Applications of Helmholtz coils range from canceling the earth’s magnetic field to generating ...

### Flow Through a Pipe Elbow

This example models the flow in a 90-degree pipe elbow. The flow is simulated using the k-omega turbulence model. The result is compared to engineering correlations.

### Tuning Fork

When a tuning fork is struck, it vibrates in a complex motion pattern that can be described mathematically as the superposition of resonant modes, also known as eigenmodes. Each mode is associated with a particular eigenfrequency. The tuning fork produces its characteristic sound from the specific timbre that is created by the combination of all of the eigenfrequencies. The Tuning Fork app ...

### 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 ...

### Bracket - Transient Analysis

The bracket models are used as an introduction to structural mechanics modeling with the Structural Mechanics Module. The following features are introduced: * The fundamentals: static linear analysis * Parametric study * Including initial strain * Modeling thermal expansion * Adding a rigid connector * Adding spring conditions * Modeling with the *Shell* interface * Transient analysis * ...

### Dielectric Slab Waveguide

A planar dielectric slab waveguide demonstrates the principles behind any kind of dielectric waveguide such as a ridge waveguide or a step-index fiber. This model solves for the effective index and fields of a dielectric slab waveguide and compares the solution to analytic results.

### Heating Circuit

Small heating circuits find use in many applications. For example, in manufacturing processes, they heat up reactive fluids. The device in this tutorial example consists of an electrically resistive layer deposited on a glass plate. The layer results in Joule heating when a voltage is applied to the circuit, which results in a structural deformation. The layer’s properties determine the amount ...