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.

Noise Radiation by a Compound Gear Train

Predicting the noise radiation from a dynamic system gives designers insight into the behavior of moving mechanisms early in the design process. For example, consider a gearbox in which the change in the gear mesh stiffness causes vibrations. These vibrations are transmitted to the gearbox housing through shafts and joints. The vibrating housing further transmits energy to the surrounding fluid, ...

Hexagonal Grating (RF)

A plane wave is incident on a reflecting hexagonal grating. The grating cell consists of a protruding semisphere. The scattering coefficients for the different diffraction orders are calculated for a few different wavelengths.

Gecko Foot

In nature, geckos use dry adhesion forces to climb walls. They have inspired researchers to develop synthetic gecko foot hairs to be used in, for example, robot applications. This model contains the nano/micro hierarchy of a synthetic gecko foot hair, where cantilever beams both in nano and micro scales describe the seta and spatula parts of one spatula stalk attached to a gecko foot. The ...

Solute Transport in Prescribed Groundwater Flow Preset Model

Predicting the transport of solutes that move with subsurface fluids is of general interest in environmental engineering and geosciences. Solutes may not only be pollutants but also artifical tracers added to the groundwater for investigation purposes. This model tracks a solute over an area of 16 square km during 1000 days in a prescribed ground water flow accounting for longitudinal and ...

Applying a Current-Voltage Switch to Models

This example exemplifies how to model the switching between current and voltage excitations in *Terminal* boundary conditions. A more detailed description of the phenomenon and the modeling process can be seen in the blog post "[Control Current and Voltage Sources with the AC/DC Module](".

Branch-Line Coupler

A Branch Line Coupler (Quadrature 90° Hybrid) is a four-port network device with a 90° phase difference between two coupled ports. The device can be used for a single antenna Transmitter/Receiver system or an I/Q signal splitter/combiner. The objective of this model is to compute the S-parameters and to observe the matching, isolation, and coupling around the operating frequency.

Combining Elastoplastic and Creep Material Models

This model shows how to combine different types of material nonlinearity, such as creep and elastoplasticity. In this specific example you will perform a stress and nonlinear strain analysis on a thick cylinder under a nonproportional loading: an initial temperature increase followed by a fluctuating pressure applied to the internal surface of the cylinder. This load case involves two ...

Mixed Diffuse-Specular Radiation Benchmark

This model shows how to use the Mathematical Particle Tracing interface to simulate mixed diffuse-specular reflection between surfaces in an enclosure. This model is separated in two parts. The first part compares the heat fluxes computed by the Mathematical Particle Tracing interface with the exact solution for two identical infinitely long parallel grey plates under mixed diffuse-specular ...

Thermionic Emission in a Planar Diode

When electrons are emitted from a heated cathode in a plane parallel vacuum diode, they contribute to the space charge density in the diode, which in turn affects the electric potential distribution. If the potential difference between the cathode and the anode is not sufficiently large, a potential minimum forms between them, repelling electrons of insufficient energy back toward the cathode. ...

Circular Waveguide Filter

A circular waveguide filter is designed using a 2D axisymmetric model. Six annular rings added to the waveguide form circular cavities connected in series, and each cavity cutoff frequency is close to the center frequency of the filter. The simulated S-parameters show a bandpass frequency response.