Model Gallery

The Model Gallery features COMSOL Multiphysics model files from a wide variety of application areas including the electrical, mechanical, fluid, and chemical disciplines. You can download ready-to-use models and step-by-step instructions for building the model, and use these as a starting point for your own modeling work. Use the Quick Search to find models relevant to your area of expertise, and login or create a COMSOL Access account that is associated with a valid COMSOL license to download the model files.

Computing the Radar Cross Section of a Perfectly Conducting Sphere

A classic benchmark problem in computational electromagnetics is to solve for the radar cross section (RCS) of a sphere in free space illuminated by a plane wave. This model solves for the RCS of a metallic sphere that has a very high conductivity, which can be treated as a material with infinite conductivity. Results are compare to the analytic solution, and agreement is shown.

Plasmonic Wire Grating

A plane wave is incident on a wire grating on a dielectric substrate. Coefficients for refraction, specular reflection, and first order diffraction are all computed as functions of the angle of incidence. The model is set up for one unit cell of the grating, flanked by Floquet boundary conditions describing the periodicity. As applied, this condition states that the solution on one side of the ...

Fresnel Equations

A plane electromagnetic wave propagating through free space is incident at an angle upon an infinite dielectric medium. This model computes the reflection and transmission coefficients and compares to the Fresnel equations.

Photonic Crystal

Photonic crystal devices are periodic structures of alternating layers of materials with different refractive indices. Waveguides that are confined inside of a photonic crystal can have very sharp low-loss bends, which may enable an increase in integration density of several orders of magnitude. This is a study of a photonic crystal waveguide. The crystal features a grid of GaAs pillars. ...

Microwave Oven

This is a model of the heating process in a microwave oven. The distributed heat source is computed in a stationary, frequency domain electromagnetic analysis followed. This is followed by a transient heat transfer simulation showing how the heat redistributes in the food.

Radar Cross Section

This tutorial model demonstrates the use of a background field in an electromagnetic scattering problem. Although this example is a boat hit by a radar, this same technique can be used in any situation where an isolated object meets electromagnetic waves from a distant source. For example, several orders of magnitude smaller, an equally common application is plasmon resonant nanoparticles. ...

Feasibility Study of Microstrip Patch Antenna Array Design

An antenna array is a group of radiating elements. By controlling the phase and magnitude of the input signal assigned to each antenna element and the number of array elements, the radiation pattern can be steered in a desired direction with a preferred level of gain. In this example, a 4 x 2 array of patch antennas is fed from a single feed point, with all elements fed at equal phase and ...

Balanced Patch Antenna for 6 GHz

Patch antennas are becoming more common in wireless equipment, like wireless LAN access points, cellular phones, and GPS handheld devices. The antennas are small in size and can be manufactured with simple and cost-effective techniques. Due to the complicated relationship between the geometry of the antenna and the electromagnetic fields, it is difficult to estimate the properties of a certain ...

Finding the Impedance of a Coaxial Cable

The coaxial cable (coax) is one of the most ubiquitous transmission line structures. It is composed of a central circular conductor, surrounded by an annular dielectric, and shielded by an outer conductor. This model computes the electric and magnetic field distribution inside of the coaxial cable, analyzes the impedance, and compares the result with the analytic solution.

Coaxial to Waveguide Coupling

Feeding a waveguide from a coaxial cable is a straightforward way to achieve electromagnetic waves inside a waveguide. Due to its small size and circular shape, the cable contributes significantly to the overall size of the problem. It is therefore necessary to keep the cable as short as possible. This model shows how to use pairs and the Port boundary conditions to feed a rectangular ...

Quick Search