HollowCylinderAxialFlux

model HollowCylinderAxialFlux "(Hollow) cylinder with axial flux; constant permeability"
    extends FluxTubes.Interfaces.PartialForce;

    SI.Length l = s "Axial length (in direction of flux)"
        annotation (Dialog(
            group = "Variable geometry",
            groupImage = "modelica://Modelica/Resources/Images/Magnetic/FluxTubes/Shapes/HollowCylinderAxialFlux.png"));
    parameter SI.Radius r_i = 0 "Inner radius of (hollow) cylinder";
    parameter SI.Radius r_o = 0.01 "Outer radius of (hollow) cylinder";
    SI.MagneticFluxDensity B "Homogeneous flux density";
protected
    parameter SI.Area A = pi * (r_o ^ 2 - r_i ^ 2) "Cross-sectional area orthogonal to direction of flux";
equation
    B = Phi / A;
    G_m = mu_0 * mu_r * A / l;
    dGmBydx = -1 * mu_0 * mu_r * A / l ^ 2 * dlBydx;

    annotation (
        defaultComponentName = "force",
        Documentation(info = "<html>\n<p>\nPlease refer to the enclosing sub-package <a href=\"modelica://Modelica.Magnetic.FluxTubes.Shapes.Force\">Force</a> for a description of all elements of this package and to <a href=\"modelica://Modelica.Magnetic.FluxTubes.UsersGuide.Literature\">[Ro41]</a> for derivation and/or coefficients of the equation for permeance G_m.\n</p>\n</html>"));
end HollowCylinderAxialFlux;