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.

Mutual Inductance and Induced Currents Between Single-Turn Coils

The mutual inductance between a primary and secondary single turn coil in a concentric coplanar arrangement is computed using a DC, steady-state, model and compared against the analytic solution. The induced currents in the secondary coil are computed using an AC, frequency-domain, analysis. The relationship between the AC induced currents and the DC inductance is discussed.

Superconducting Wire

Superconducting materials have zero resistivity up to a certain critical current density, above which the resistivity increases rapidly. To model such a material, this model uses a PDE, General Form interface with second-order vector elements. The model was based on a suggestion by Dr. Roberto Brambilla, CESI - Superconductivity Dept., Milano, Italy.

Electrodynamic Bearing

This model illustrates the working principle of a passive electrodynamic bearing. An electrically conducting rotor rotating in a magnetic field produced by a permanent magnets induces eddy currents on the conducting rotor. The eddy currents, in turn, produce a magnetic field that opposes the magnetic fields by the magnets and induces a force that opposes the motion of the rotor. The radial ...

One-Sided Magnet and Plate

Permanent magnets with a one-sided flux have many uses. The one-sided flux behavior is obtained by giving the magnet a magnetization that varies in the lateral direction. This model shows this technique to model a cylindrical one-sided permanent magnet. A special technique to model thin sheets of high permeability material was used to model a thin metal plate next to the magnet. This ...

Iron Sphere in a 20 kHz Magnetic Field

An iron sphere is exposed to a spatially uniform, sinusoidally time-varying, background magnetic field. The frequency of the field is such that there skin depth is smaller than the sphere radius. The induced currents in the sphere and the perturbation to the background field are computed. Proper meshing of domains with significant skin effect is addressed.

Tunable MEMS Capacitor

The electrostatically tunable parallel plate capacitor in this example is a typical component in various MEMS devices for radio frequencies that range between 300 MHz and 300 GHz. You can modify the distance between the two plates, as the applied voltage changes, through a spring attached to one of the plates. A postprocessing step then computes the capacitance. The example uses the ...

Busbar, AC Analysis

This is a busbar configuration with an AC analysis. The configuration is similar to the introductory tutorial in the book Introduction to COMSOL Multiphysics. However, two conductors are added to represent a more realistic case of magnetic fields surrounding the busbar. The results include Lorentz forces, induced currents, magnetic flux, and temperature.

Effective Nonlinear Magnetic Curves Calculator

The Effective Nonlinear Magnetic Curves Calculator application is a companion to the *Effective Nonlinear Constitutive Relations* functionality. Magnetic-based interfaces in the AC/DC Module support the Effective HB/BH Curve material model that can be used to approximate the behavior of a nonlinear magnetic material in a frequency domain simulation without the additional computational cost of a ...

Relativistic Diverging Electron Beam

When modeling the propagation of charged particle beams at high currents and relativistic speeds, the space charge and beam current create significant electric and magnetic forces that tend to expand and focus the beam, respectively. The *Charged Particle Tracing* interface uses an iterative procedure, in this example, to efficiently compute the strongly coupled particle trajectories and ...

Static Field Modeling of a Halbach Rotor

This model presents the static field modeling of an outward flux focusing magnetic rotor using permanent magnets. This magnetic rotor is also often called a Halbach rotor. The use of permanent magnets in rotatory devices such as motors, generators and magnetic gears is increasing. The accurate modeling of a permanent magnets fields is important. This model illustrates how to calculate the ...