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# 3d_magnetron

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# 3d_magnetron

 { 3D_MAGNETRON.PDE  MODEL OF A GENERIC MAGNETRON IN 3D    The development of this model is  described in the Magnetostatics chapter  section.   }   TITLE 'Oval Magnet '   COORDINATES  CARTESIAN3   SELECT  ngrid=25 alias(x) = "X(cm)" alias(y) = "Y(cm)" alias(z) = "Z(cm)"   VARIABLES  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

Mz = 0       ! global magnetization variable

Nx = vector(0,Mz,0)

Ny = vector(-Mz,0,0)

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

Bxx= -dz(Ay)

Byy= dz(Ax) ! unfortunately, "By" is a reserved word.

Bzz= dx(Ay)-dy(Ax)

EQUATIONS

Ax:   div(grad(Ax)/mu+Nx) = 0

Ay:   div(grad(Ay)/mu+Ny) = 0

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(Ax)=0 value(Ay)=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