Magnetostatics¶

MAGNETOSTATICS solves the static magnetic field of magnets, steel and coil drives. A solid frame solves it in 3D, and an axisymmetric or Cartesian 2D frame solves it as MAGNETOSTATICS_2D on the r-z half-plane or a planar section. See Conditions and physics for how conditions attach and where they land.

Frame	Solves as	Solver stack
Solid	`MAGNETOSTATICS`	MagnetoDynamicsSolver, MagnetoDynamicsCalcFieldsSolver, SaveScalarsSolver, ResultOutputSolver
Axisymmetric	`MAGNETOSTATICS_2D`	MagnetoDynamics2DSolver, MagnetoDynamicsCalcFieldsSolver, SaveScalarsSolver, ResultOutputSolver
Cartesian2D	`MAGNETOSTATICS_2D`	MagnetoDynamics2DSolver, MagnetoDynamicsCalcFieldsSolver, SaveScalarsSolver, ResultOutputSolver

Material-wired conditions¶

Condition	Target	Sets	Frames
`Magnetization`	body	`direction`	Solid, Axisymmetric, Cartesian2D

Magnetization¶

Physics MAGNETOSTATICS · Target body · Section Material · Kind magnetization · API Magnetization

The magnetization direction of a permanent magnet.

Field	Symbol	Unit	Meaning	Sif keyword	Default
`direction`			Magnetization direction in the authored model's frame, None for an unmagnetized body; magnitude comes from the material.		required

Writes: The Magnetization components of magnitude (A/m) along the direction, in frame's solve coordinates.

The material's remanence sets the strength, so a magnet body needs both a magnet material, such as N52, and a Magnetization with a direction.

Body forces¶

Condition	Target	Sets	Frames
`CurrentDensity`	body	`value` [A/m²]	Axisymmetric, Cartesian2D

CurrentDensity¶

Physics MAGNETOSTATICS_2D · Target body · Section Body Force · Kind current_density · API CurrentDensity

A uniform signed out-of-plane current density J = N·I/A over a winding window, the homogenized drive of a stranded coil in a 2D solve.

Field	Symbol	Unit	Meaning	Sif keyword	Default
`value`	`J`	A/m²	Signed out-of-plane current density imposed uniformly over the body: azimuthal under Axisymmetric, along +normal under Cartesian2D.	`Current Density`	required

CurrentDensity drives only the 2D solve, azimuthal under an axisymmetric frame and along the normal under a Cartesian 2D one; a solid frame rejects it. See Axisymmetric and Cartesian 2D.

Components¶

Condition	Target	Sets	Frames
`CalculateMagneticForce`	body	`label`, `calculate_magnetic_force`, `calculate_magnetic_torque`, `torque_origin` [m], `torque_axis`	Solid, Axisymmetric, Cartesian2D

CalculateMagneticForce¶

Physics MAGNETOSTATICS · Target body · Section Component · Kind calculate_magnetic_force · API CalculateMagneticForce

Lumps the magnetic force, and optionally the torque, over the bodies its tag matches into one Elmer Component.

Field	Symbol	Unit	Meaning	Default
`label`			The Component's `Name`; None uses the authoring tag's name.	`None`
`calculate_magnetic_force`			Lump the nodal magnetic force over the master bodies.	`True`
`calculate_magnetic_torque`			Also lump the magnetic torque (requires `torque_origin`/`torque_axis`).	`False`
`torque_origin`	`r_0`	m	Torque pivot point.	`None`
`torque_axis`			Torque axis direction.	`None`

Writes: The CalcFields force and torque flags, plus the torque origin and axis when set.

The result reads the lumped force and torque back by the Component's name, as result.component_forces[label] and result.component_torques[label]. An axisymmetric or Cartesian 2D frame lumps no torque, so it rejects the torque fields.