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Diffusion FENNECS: Finite Element Non-Neutral Electron Cloud Simulator (master) Browse

fennecs/matlab/@espic2dhdf5/displayVacuumTrap.m
b5d0d2ce89e3master

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displayVacuumTrap.m
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function displayVacuumTrap(obj,time2d)
% Plot the larmor radius for created particles with low energy
% the larmor radius is calculated by considering that the
% initial perpendicular velocity \approx the ExB velocity
% potential well is shown with isolines on top
if iscell(time2d)
time2d=cell2mat(time2d);
end
[zgrid,rgrid]=ndgrid(obj.zgrid,obj.rgrid);
geomw=obj.geomweight(:,:,1);
inside=griddedInterpolant(zgrid,rgrid,obj.geomweight(:,:,1)');
% Compute the Larmor radius assuming v_perp=v_exb
if time2d>0
Er=obj.Er(:,:,time2d);
Ez=obj.Ez(:,:,time2d);
else
Er=obj.Erxt(:,:,1);
Ez=obj.Ezxt(:,:,1);
end
rl=abs(obj.me/obj.qe*(-Er.*obj.Bz'+Ez.*obj.Br')./(obj.B.^3)');
% Remove the points outside the geometry
rl(obj.geomweight(:,:,1)<0)=0;
% calculate the normal vector to the magnetic field lines at each position
perpB=zeros(size(obj.sinthet,1),size(obj.sinthet,2),2);
perpB(:,:,1)=sign(-Er).*obj.sinthet;
perpB(:,:,2)=-sign(-Er).*obj.costhet;
pos=zeros(size(obj.sinthet,1),size(obj.sinthet,2),2);
pos(:,:,1)=rgrid';
pos(:,:,2)=zgrid';
posu=pos+2*rl.*perpB;
isinside=inside(posu(:,:,2),posu(:,:,1))>0;
model=obj.potentialwellmodel(time2d,true);
z=model.z;
r=model.r;
Pot=model.pot;
Potdepth=scatteredInterpolant(z',r',Pot);
effectdepth=0.5*(Potdepth(posu(:,:,2),posu(:,:,1))+Potdepth(pos(:,:,2),pos(:,:,1)));
effectdepth(geomw<0)=NaN;
effectdepth(~isinside)=NaN;
effectdepth(effectdepth<0)=NaN;
f=figure;
contourf(obj.zgrid,obj.rgrid,effectdepth,40,'edgecolor','none')
hold on
contour(obj.zgrid,obj.rgrid,geomw,[0 0],'r-')
N=obj.N(:,:,end);
N=N/max(N(:));
contour(obj.zgrid,obj.rgrid,N,'k--')
colormap(jet)
xlabel('z [m]')
ylabel('r [m]')
c=colorbar;
c.Label.String='Effective well [eV]';
papsize=[14 8];
obj.savegraph(f,sprintf('%s/%s_effwellr_rl_%i',obj.folder,obj.name,floor(mean(time2d))),papsize);
end
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