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# 3d_vector_magnetron

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# 3d_vector_magnetron

{ 3D_VECTOR_MAGNETRON

MODEL OF A GENERIC MAGNETRON IN 3D USING VECTOR VARIABLES

This is a modification of 3D_MAGNETRON.PDE.

The development of this model is described in the Magnetostatics chapter of the

Electromagnetic Applications section.

}

TITLE 'Oval Magnet'

COORDINATES

CARTESIAN3

SELECT

ngrid=25

alias(x) = "X(cm)"

alias(y) = "Y(cm)"

alias(z) = "Z(cm)"

VARIABLES

A = vector (Ax,Ay)       { assume Az is zero! }

DEFINITIONS

MuMag=1.0 ! Permeabilities:

MuAir=1.0

MuSST=1000

MuTarget=1.0

Mu=MuAir ! default to Air

MzMag = 10000   ! permanent magnet strength

Mx=0   My=0   Mz=0

M = vector(Mx,My,Mz)     ! global magnetization variable

N = tensor((0,Mz,0),(-Mz,0,0),(0,0,0))

B = curl(Ax,Ay,0) ! magnetic induction vector

Bxx= xcomp(B)

Byy= ycomp(B) ! unfortunately, "By" is a reserved word.

Bzz= zcomp(B)

EQUATIONS

EXTRUSION

SURFACE "Boundary Bottom"     Z=-5

SURFACE "Magnet Plate Bottom" Z=0

LAYER "Magnet Plate"

SURFACE "Magnet Plate Top"    Z=1

LAYER "Magnet"

SURFACE "Magnet Top"      Z=2

SURFACE "Boundary Top"    Z=8

BOUNDARIES

Surface "boundary bottom" value (Ax)=0 value(Ay)=0

Surface "boundary top"   value (Ax)=0 value(Ay)=0

REGION 1     {Air bounded by conductive box }

START (20,-10)

value(A)=vector(0,0,0)

ARC(center=20,0) angle=180

LINE TO (-20,10)

ARC(center=-20,0) angle=180

LINE TO CLOSE

LIMITED REGION 2     { Magnet Plate }

LAYER "Magnet Plate" Mu=MuSST

LAYER "Magnet" Mu=MuMag  Mz = MzMag

START (20,-8)

ARC(center=20,0) angle=180

LINE TO (-20,8)

ARC(center=-20,0) angle=180

LINE TO CLOSE

LIMITED REGION 3     { Inner Gap  }

LAYER "Magnet"

START (20,-6)

ARC(center=20,0) angle=180

LINE TO (-20,6)

ARC(center=-20,0) angle=180

LINE TO CLOSE

LIMITED REGION 4     {Inner Magnet }

LAYER "Magnet" Mu=MuMag  Mz = -MzMag

START (20,-2)

ARC(center=20,0) angle=180

LINE TO (-20,2)

ARC(center=-20,0) angle=180

LINE TO CLOSE

MONITORS

grid(y,z) on x=0

grid(x,z) on y=0

grid(x,y) on z=1.01

contour(Ax) on x=0

contour(Ay) on y=0

PLOTS

grid(y,z) on x=0

grid(x,z) on y=0

grid(x,y) on z=1.01

contour(Ax) on x=0

contour(Ay) on y=0

vector(Bxx,Byy) on z=2.01  norm

vector(Byy,Bzz) on x=0  norm

vector(Bxx,Bzz) on y=4  norm

contour(magnitude(Bxx,Byy,Bzz)) on z=2

END