モデル・ギャラリー
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.
Cold Crucible
A cold crucible is used for the manufacturing of alloys that require a high degree of purity, like titanium alloys for the aeronautic industry. The cold crucible in this model is made of several water-cooled copper sectors that form the container in which the alloy is manufactured. The harmonic current flowing in the coils will induce a current in the crucible flowing in the opposite ...
Electric Shielding Comparison
The electric shielding boundary condition is meant to approximate a thin layer of highly conductive material that provides an additional current path tangential to a boundary. This example compares the electric shielding boundary condition to a full-fidelity model and discusses the range of applicability of this boundary condition.
Magnetotellurics
Magnetotellurics is a method for estimating the resistivity profile of the Earth's subsurface using the natural electromagnetic source provided by the ionosphere. This model was defined by Zhdanov et al. in a study published in 1997. In this article, various scientific groups compared software performance on the same models. This is the model called COMMEMI-3D-2, which has become one of the ...
Thin Low Permittivity Gap Comparison
The thin low permittivity gap boundary condition is meant to approximate a thin layer of material with low relative permittivity compared to its surroundings. This boundary condition is available for electrostatic field modeling. This example compares the thin low permittivity gap boundary condition to a full-fidelity model and discusses the range of applicability of this boundary condition.
Quadrupole Mass Filter
A quadrupole mass filter (QMF) is a key component of a modern mass spectrometer. A QMF uses direct current (DC) and alternating current (AC) electric fields to analyze positive or negative ions by mass to charge ratio. A QMF consists of 4 parallel rods spaced equidistantly, the ratio of the rod radius to the radius of the inscribed circle is 1.148. Opposite pairs of rods are electrically ...
Magnetic Gear in 2D
This model presents the transient modeling of a coaxial magnetic bearing using permanent magnets. The coaxial magnetic bearing is advantageous over the conventional mechanical gear mainly because of minimum noise, maintenance free operation, overload protection and physical isolation between the parts. The typical application of this device is for a high speed reduction ratio such as in wind ...
Iron Sphere in a 13.56 MHz Magnetic Field
An iron sphere is exposed to a spatially uniform, sinusoidally time-varying, background magnetic field. The frequency of the field is so high that the skin depth in the sphere is much smaller than the radius. At such high frequencies it is possible to model only the fields and induced currents on the surface of the sphere, thus avoiding the need for solving for the fields within the volume of the ...
Multipactor
Multipaction can occur when electrons are accelerated by a high frequency RF field into surfaces. Secondary electron emission can occur and under the right conditions there can be an exponential growth in the number of electrons. The multipaction effect is strongest at a specific RF frequency, which depends on the dimensions of the device and the applied voltage.\n\nThis model requires the ...
Capacitance in a Microstrip
To illustrate how to calculate lumped parameters of capacitance, this model calculates such in a microstrip. The example shows the two different ways of calculating this: with a static analysis and with a time-harmonic analysis.
