Leakage

Leakage flux tubes with position-independent permeance and hence no force generation; mu_r=1

Package Contents

QuarterCylinder

Leakage flux from one edge to the opposite plane through a quarter cylinder

QuarterHollowCylinder

Leakage flux in circumferential direction through a quarter hollow cylinder

HalfCylinder

Leakage flux through the edges of a half cylinder

HalfHollowCylinder

Leakage flux in circumferential direction through a half hollow cylinder

QuarterSphere

Leakage flux through the corners of a quarter sphere

QuarterHollowSphere

Leakage flux through the edges of a quarter hollow sphere

EighthOfSphere

Leakage flux through one edge and the opposite plane of an eighth of a sphere

EighthOfHollowSphere

Leakage flux through one edge and the opposite plane of an eighth of a hollow sphere

CoaxCylindersEndFaces

Leakage flux between the end planes of a inner solid cylinder and a coaxial outer hollow cylinder

Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

Please have a look at UsersGuide.ReluctanceForceCalculation for an explanation of the different flux tube categories and resulting sub-packages.

The permeances of all elements of this package are calculated from their geometry. These flux tube elements are intended for modelling of leakage fields through vacuum, air and other media with a relative permeability mu_r=1. Basic.LeakageWithCoefficient accounts for leakage not by the geometry of flux tubes, but by a coupling coefficient c_usefulFlux.

All dimensions are defined as parameters. As a result, the shape of these elements will remain constant during dynamic simulation of actuators and reluctance forces will not be generated in these flux tube elements. A simple leakage flux tube with reluctance force generation is provided with the element Force.LeakageAroundPoles. In cases where the accuracy of that element is not sufficient, the leakage elements of this package can be adapted and extended so that they are able to change their shape with armature motion and to generate reluctance forces. This requires an extension of the partial model Interfaces.PartialForce, a higher variability of the variables representing the flux tube's dimensions, definition of a relationship between armature position and these dimensions and determination of the analytic derivative dG_m/dx of the flux tube's permeance G_m with respect to armature position x.