La Bibliothèque de Modèles présente des modèles construits avec COMSOL Multiphysics pour la simulation d'une très grande variété d'applications, dans les domaines électrique, mécanique, fluidique et chimique. Vous pouvez télécharger ces modèles résolus avec leur documentation détaillée, notamment les instructions de construction pas à pas, et vous en servir comme point de départ de votre travail de simulation. Utilisez l'outil de recherche rapide pour trouver les modèles correspondant à votre domaine d'intérêt, et connectez vous avec votre compte COMSOL Access, associé à une licence COMSOL, afin de télécharger les fichiers modèles.

Electromagnetic Plunger with Stopper

This is a transient model of an electromagnetic plunger with stopper restricting the linear motion. The model consists of a magnetic core, nonmagnetic guider, multi-turn coil, nonmagnetic stopper/blocker, and magnetic plunger attached to the spring and damper at the far end. The electromagnetic force on the plunger due to the transient current in the coil is calculated using the Maxwell stress ...

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.

Magnetic Signature of a Submarine

A vessel traveling on the surface or under water gives rise to detectable local disturbances in the Earth’s magnetic field. These disturbances can be used to trigger weapon systems. The magnetic signature of a ship can be reduced by generating a counteracting magnetic field of suitable strength and direction based on prior knowledge of the magnetic properties of the vessel. This model ...

A Geoelectrical Forward Problem

The classical forward problem of geoelectrics (includes electrical resistivity tomography, ERT and earlier techniques as vertical electric sounding, VES) is the calculation of potentials at a given set of electrodes (M,N) while current is injected at other electrodes (A,B) into the ground. Typically the physical domain (earth) is unbounded to the sides and the bottom because of which one needs ...

Comparison of Effective HB/BH Curve with Linear and Nonlinear Material Models

This example illustrates how to setup the Effective HB/BH Curve material model, introduced in COMSOL 5.2, for modeling the magnetic materials in frequency domain. The model also compares the results from Effective HB/BH Curve model with the linear and nonlinear HB/BH Curve material model in 2D.

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 ...

External Material, AC/DC Module, General HB/BH relation

The AC/DC magnetic interfaces now support material models defined in external C code. A new way to specify user-defined material models is included in COMSOL Multiphysics version 5.2. You can now access external material functions, written in C code, which have been compiled into a shared library. By writing a wrapper function in C code, you can also use material functions written in another ...

Electrodynamic Wheel Magnetic Levitation in 2D

This model illustrates the working principle of an electrodynamic wheel (EDW) magnetic levitation system. EDW magnetic levitation system consists of rotating and/or translationally moving permanent magnet Halbach rotor above a passive conducting guideway/track. Eddy current is induced in the guideway due to the rotation and/or translational motion of the Halbach rotor. The induced eddy ...

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 ...

Magnetically Permeable Sphere in a Static Magnetic Field

A sphere of relative permeability greater than unity is exposed to a spatially uniform static background magnetic field. Two formulations are used to solve this problem, and the differences between these are discussed. The field strength inside the sphere is computed and compared against the analytic solution.