Quadrupole Mass Spectrometer
The principle component of a quadrupole mass spectrometer is the mass filter which is used to filter ions with different charge to mass ratios. The quadrupole mass filter has been well studied over the years, Ref. 1 and the physics and optimal design are well understood. In a real quadrupole mass spectrometer, fringe fields exist at both the entrance and exit of the mass filter. These fringe ...
Dielectric Shielding Comparison
The dielectric shielding boundary condition is meant to approximate a thin layer of material with high relative permittivity compared to its surroundings. This boundary condition is available for electrostatic field modeling. This example compares the dielectric shielding boundary condition to a full-fidelity model and discusses the range of applicability of this boundary condition.
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 ...
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 ...
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 ...
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 ...
Inductive Liquid Metal Pump
Induction pumps are used in high temperature cooling systems. The principle of operation is equivalent to a linear three phase induction motor. The lack of moving parts and the pumped liquid being kept in a hermetically closed system are clear advantages. This model shows how to simulate a generic liquid Na pump.
Quadrupole Lens
Just like optical lenses focus light, electric and magnetic lenses can focus beams of charged particles. Systems of magnetic quadrupole lenses find a common use in focusing both ion and particle beams in accelerators at nuclear and particle physics centers. This model shows the path of ions going through three consecutive magnetic quadrupole lenses. The model also takes fringing fields ...
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 ...
Magnetic Prospecting of Iron Ore Deposits
Magnetic prospecting is a geological exploration method that is applicable to certain types of iron ore deposits, in particular those made up of magnetite and hematite. The method consists of measuring the magnetic anomalies (changes in the earth's magnetic field) due to the presence of magnetic ores. The Magnetic Prospecting app simulates the effect of a deposit of magnetic ore on the earth's ...
