Magnetic Forces, Rotating Machinery
Use Magnetic Forces, Rotating Machinery () coupling to model interaction between deformable solids and rotating magnetic fields, particularly in case when the rotation and deformations of the structure can significantly affect the magnetic field distribution.
The presence of such multiphysics node in the model will enforce the Include geometric nonlinearity option on all applicable study nodes.
Settings
The Label is the default multiphysics coupling feature name.
The Name is used primarily as a scope prefix for variables defined by the coupling node. Refer to such variables in expressions using the pattern <name>.<variable_name>. In order to distinguish between variables belonging to different coupling nodes or physics interfaces, the name string must be unique. Only letters, numbers, and underscores (_) are permitted in the Name field. The first character must be a letter.
The default Name (for the first multiphysics coupling feature in the model) is mfrm1.
Domain Selection
The domain selection includes by default all applicable domains. Such domains represent an intersection of the applicable domains under the corresponding Structure and Rotating machinery, magnetic interfaces selected in the coupling feature.
In Rotating Machinery, Magnetic interface, the following domain features are applicable:
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Ampère’s Law, if its material type input is set to Solid. Use this domain feature for solid magnetic materials.
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Magnetic Flux Conservation, if its material type input is set to Solid. Use this domain feature for solid magnetic materials.
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Nonconducting Magnet
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Conducting Magnet
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Ampère’s Law, Nonlinear Magnetostrictive
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Passive Conductor
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Coil, if its material type input is set to Solid. You can use this feature to represent current carrying solid domains such as coils and wires.
In the Structure interface, the following domain material features are applicable:
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Linear Elastic Material
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Nonlinear Magnetostrictive Material
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Nonlinear Elastic Material (with the Nonlinear Structural Materials Module)
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Hyperelastic Material (with the Nonlinear Structural Materials Module)
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Rigid Material.
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For nonsolid magnetic domains, remove them from the Structure interface selection but keep them selected in the Rotating Machinery, Magnetic interface selection.
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Ampère’s Law, Nonlinear Magnetostrictive is a part of The Nonlinear Magnetostriction Interface. The corresponding multiphysics coupling feature, Nonlinear Magnetostriction, can be combined with Magnetic Forces, Rotating Machinery.
See also
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Magnetomechanics
Coupled interfaces
This section defines the physics interfaces involved in this Magnetic Forces, Rotating Machinery coupling. The Structure and Rotating Machinery, Magnetic lists include all applicable physics interfaces.
Select Structure — Solid Mechanics or Multibody Dynamics.
Select Rotating machinery, magnetic — Rotating Machinery, Magnetic.
The default values depend on how the node is created.
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If it is added from the Physics ribbon (Windows users), Physics contextual toolbar (Mac and Linux users), or context menu (all users), then the first physics interface of each type in the component is selected as the default.
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If it is added automatically when the physics interface is chosen in the Model Wizard or Add Physics window, then the two participating physics interfaces are selected.
You can also select None from either list to uncouple the coupling from a physics interface. If the physics interface is removed from the Model Builder, for example Solid Mechanics is deleted, then the Structure list defaults to None as there is nothing to couple to.
If a physics interface is deleted and then added to the model again, then in order to reestablish the coupling, you need to choose the physics interface again from the lists. This is applicable to all multiphysics coupling nodes that would normally default to the once present physics interface. See Multiphysics Modeling Workflow in the COMSOL Multiphysics Reference Manual.