Hi everyone!
I'm trying to create a geometry file that consists of a ring that has a
'unit cell' (n holes) that is repeated along the circumference of the
ring to fill it out completely.
I'm at the point where I can do a single unit cell that is completely
general, but I've been having trouble replicating it along the rest of
the ring.
This is what I attempted, which just creates a single circle of the
wrong tag. Would anyone know what I'm supposed to put in the argument
for the tag of the Disk()? If that's not where the problem lies, would
anyone have any other idea?
For (1 : N-1 : 1)
For (0 : n : 1)
Disk(news) = {R*Cos(N*beta+n*alpha), R*Sin(N*beta+n*alpha), 0, r, r};
EndFor
EndFor
And what I'm trying to generalize (which I can confirm does what I want):
Disk(6) = {R*Cos(beta), R*Sin(beta), 0, r, r};
Disk(7) = {R*Cos(beta+alpha), R*Sin(beta+alpha), 0, r, r};
Disk(8) = {R*Cos(beta+2*alpha), R*Sin(beta+2*alpha), 0, r, r};
Disk(9) = {R*Cos(2*beta), R*Sin(2*beta), 0, r, r};
Disk(10) = {R*Cos(2*beta+alpha), R*Sin(2*beta+alpha), 0, r, r};
Disk(11) = {R*Cos(2*beta+2*alpha), R*Sin(2*beta+2*alpha), 0, r, r};
(Block of 3 lines is repeated similarly N-1 times around circumference.
Attached is the script I've been working on.
Kind Regards,
Alexis.
SetFactory("OpenCASCADE");
// Reasonable defaults here were picked (zoom way the hell in to see the
dielectric properly).
N = DefineNumber[ 8, Name "Parameters/N" ]; // Number of unit cells in the ring.
a = DefineNumber[ 0.1, Name "Parameters/a" ]; // Arc length between air holes
within the same unit cell.
n = DefineNumber[ 2, Name "Parameters/n" ]; // Number of holes in a unit cell.
d = DefineNumber[ 0.1, Name "Parameters/d" ]; // Arc length separation at the
start and end of the unit cell.
w = DefineNumber[ 0.1, Name "Parameters/w" ]; // Ring width of the dielectric.
r = DefineNumber[ 0.04, Name "Parameters/r" ]; // Radius of the air holes.
L = 2*d+(n-1)*a; // Total arc length of a unit cell.
R = N*L/(2*Pi); // Required radius of the dielectric, from origin to half the
width of the ring.
beta = 2*Pi/N; // Required angle of R.
delta = d/R; // Angle of d.
alpha = a/R; // Angle of a.
// 2 paramaters of the pml, constructed similarly to dielectric ring.
pml_r = DefineNumber[ 10., Name "Parameters/pml_r" ];
pml_w = DefineNumber[ 3., Name "Parameters/pml_w" ];
Point(1) = {0, 0, 0, 1.0};
Disk(1) = {-0, 0, 0, R+w/2, R+w/2};
Disk(2) = {-0, 0, 0, R-w/2, R-w/2};
Disk(3) = {0, 0, 0, pml_r-pml_w/2, pml_r-pml_w/2};
Disk(4) = {0, 0, 0, pml_r+pml_w/2, pml_r+pml_w/2};
Point(6) = {R, 0, 0, 1.0};
Macro UnitCell
If (n*N == 0)
Printf("There are no air holes."); // An exception for no air holes.
ElseIf (n == 1)
For N In {1: N: 1}
Disk(5) = {R, 0, 0, r, r};
Rotate {{0, 0, 1}, {0, 0, 0}, beta} { // Exception for n=1: it just copies that
first hole over the circle.
Duplicata { Curve{4+N}; }
}
EndFor
Printf("Ignore the errors: the n=1 case works as expected.");
Else
Disk(5) = {R, 0, 0, r, r};
For n In {1: n-1: 1}
Rotate {{0, 0, 1}, {0, 0, 0}, alpha} {
Duplicata { Curve{4+n}; }
}
EndFor
EndIf
Return
// Basically this function makes a unit cell (if n>1) by copying disk 5 n-1
times.
// It is copied+rotated by alpha each time (but can not applied delta rotation
yet).
Call UnitCell;
/*
For (1 : N-1 : 1)
For (0 : n : 1)
Disk(news) = {R*Cos(N*beta+n*alpha), R*Sin(N*beta+n*alpha), 0, r, r};
EndFor
EndFor
*/
/*
Disk(6) = {R*Cos(beta), R*Sin(beta), 0, r, r};
Disk(7) = {R*Cos(beta+alpha), R*Sin(beta+alpha), 0, r, r};
Disk(8) = {R*Cos(beta+2*alpha), R*Sin(beta+2*alpha), 0, r, r};
Disk(9) = {R*Cos(2*beta), R*Sin(2*beta), 0, r, r};
Disk(10) = {R*Cos(2*beta+alpha), R*Sin(2*beta+alpha), 0, r, r};
Disk(11) = {R*Cos(2*beta+2*alpha), R*Sin(2*beta+2*alpha), 0, r, r};
*/
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