--- /dev/null
+function [Fx,Fy]=Ufvsgcurrent3(mesh,u,alpha,gamma,eta,beta);
+
+
+ ## -*- texinfo -*-
+ ##
+ ## @deftypefn {Function File} {[@var{jx},@var{jy}]} = Ufvsgcurrent3 @
+ ## (@var{mesh}, @var{u}, @var{alpha}, @var{gamma}, @var{eta}, @var{beta});
+ ##
+ ##
+ ## Builds the Scharfetter-Gummel approximation of the vector
+ ## field
+ ##
+ ## @iftex
+ ## @tex
+ ## $ \vect{J}(u) = \alpha \gamma (\eta\vect{\nabla}u-\vect{beta}u) $
+ ## @end tex
+ ## @end iftex
+ ## @ifinfo
+ ## J(@var{u}) = @var{alpha}* @var{gamma} * (@var{eta} * grad @var{u} - @var{beta} * @var{u}))
+ ## @end ifinfo
+ ##
+ ## where:
+ ## @itemize @minus
+ ## @item @var{alpha} is an element-wise constant scalar function
+ ## @item @var{eta}, @var{u}, @var{gamma} are piecewise linear
+ ## conforming scalar functions
+ ## @item @var{beta} is an element-wise constant vector function
+ ## @end itemize
+ ##
+ ## J(@var{u}) is an element-wise constant vector function
+ ##
+ ## Instead of passing the vector field @var{beta} directly
+ ## one can pass a piecewise linear conforming scalar function
+ ## @var{phi} as the last input. In such case @var{beta} = grad @var{phi}
+ ## is assumed. If @var{phi} is a single scalar value @var{beta}
+ ## is assumed to be 0 in the whole domain.
+ ##
+ ## @seealso{Uscharfettergummel3}
+ ## @end deftypefn
+
+ %% This file is part of
+ %%
+ %% SECS2D - A 2-D Drift--Diffusion Semiconductor Device Simulator
+ %% -------------------------------------------------------------------
+ %% Copyright (C) 2004-2006 Carlo de Falco
+ %%
+ %%
+ %%
+ %% SECS2D is free software; you can redistribute it and/or modify
+ %% it under the terms of the GNU General Public License as published by
+ %% the Free Software Foundation; either version 2 of the License, or
+ %% (at your option) any later version.
+ %%
+ %% SECS2D is distributed in the hope that it will be useful,
+ %% but WITHOUT ANY WARRANTY; without even the implied warranty of
+ %% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ %% GNU General Public License for more details.
+ %%
+ %% Youx should have received a copy of the GNU General Public License
+ %% along with SECS2D; If not, see <http://www.gnu.org/licenses/>.
+
+ Nelem = columns(mesh.t);
+ Nnodes = columns(mesh.p);
+
+ uloc = u(mesh.t(1:3,:));
+
+ shgx = reshape(mesh.shg(1,:,:),3,Nelem);
+ shgy = reshape(mesh.shg(2,:,:),3,Nelem);
+
+ x = reshape(mesh.p(1,mesh.t(1:3,:)),3,[]);
+ dx = [ (x(3,:)-x(2,:)) ;
+ (x(1,:)-x(3,:)) ;
+ (x(2,:)-x(1,:)) ];
+
+ y = reshape(mesh.p(2,mesh.t(1:3,:)),3,[]);
+ dy = [ (y(3,:)-y(2,:)) ;
+ (y(1,:) -y(3,:)) ;
+ (y(2,:) -y(1,:)) ];
+
+ ##ei = sqrt( dx.^2 + dy.^2 );
+
+ if all(size(beta)==1)
+ v12=0;v23=0;v31=0;
+ elseif all(size(beta)==[2,Nelem])
+ v23 = beta(1,:) .* dx(1,:) + beta(2,:) .* dy(1,:);
+ v31 = beta(1,:) .* dx(2,:) + beta(2,:) .* dy(2,:);
+ v12 = beta(1,:) .* dx(3,:) + beta(2,:) .* dy(3,:);
+ elseif all(size(beta)==[Nnodes,1])
+ betaloc = beta(mesh.t(1:3,:));
+ v23 = betaloc(3,:)-betaloc(2,:);
+ v31 = betaloc(1,:)-betaloc(3,:);
+ v12 = betaloc(2,:)-betaloc(1,:);
+ end
+
+ etaloc = eta(mesh.t(1:3,:));
+
+ eta23 = etaloc(3,:)-etaloc(2,:);
+ eta31 = etaloc(1,:)-etaloc(3,:);
+ eta12 = etaloc(2,:)-etaloc(1,:);
+
+ etalocm1 = Utemplogm(etaloc(2,:),etaloc(3,:));
+ etalocm2 = Utemplogm(etaloc(3,:),etaloc(1,:));
+ etalocm3 = Utemplogm(etaloc(1,:),etaloc(2,:));
+
+ gammaloc = gamma(mesh.t(1:3,:));
+ geloc = gammaloc.*etaloc;
+
+ gelocm1 = Utemplogm(geloc(2,:),geloc(3,:));
+ gelocm2 = Utemplogm(geloc(3,:),geloc(1,:));
+ gelocm3 = Utemplogm(geloc(1,:),geloc(2,:));
+
+ [bp23,bm23] = Ubern( (v23 - eta23)./etalocm1);
+ [bp31,bm31] = Ubern( (v31 - eta31)./etalocm2);
+ [bp12,bm12] = Ubern( (v12 - eta12)./etalocm3);
+
+ gfigfj = [ shgx(3,:) .* shgx(2,:) + shgy(3,:) .* shgy(2,:) ;
+ shgx(1,:) .* shgx(3,:) + shgy(1,:) .* shgy(3,:) ;
+ shgx(2,:) .* shgx(1,:) + shgy(2,:) .* shgy(1,:) ];
+
+ Fx = - alpha' .* ( gelocm1 .* etalocm1 .* dx(1,:) .* ...
+ gfigfj(1,:) .* ...
+ ( bp23 .* uloc(3,:)./etaloc(3,:) -...
+ bm23 .* uloc(2,:)./etaloc(2,:)) +... %% 1
+ gelocm2 .* etalocm2 .* dx(2,:) .* ...
+ gfigfj(2,:) .* ...
+ (bp31 .* uloc(1,:)./etaloc(1,:) -...
+ bm31 .* uloc(3,:)./etaloc(3,:)) +... %% 2
+ gelocm3 .* etalocm3 .* dx(3,:) .* ...
+ gfigfj(3,:) .* ...
+ (bp12 .* uloc(2,:)./etaloc(2,:) -...
+ bm12 .* uloc(1,:)./etaloc(1,:)) ... %% 3
+ );
+
+ Fy = - alpha' .* ( gelocm1 .* etalocm1 .* dy(1,:) .* ...
+ gfigfj(1,:) .* ...
+ ( bp23 .* uloc(3,:)./etaloc(3,:) -...
+ bm23 .* uloc(2,:)./etaloc(2,:)) +... %% 1
+ gelocm2 .* etalocm2 .* dy(2,:) .* ...
+ gfigfj(2,:) .* ...
+ (bp31 .* uloc(1,:)./etaloc(1,:) -...
+ bm31 .* uloc(3,:)./etaloc(3,:)) +... %% 2
+ gelocm3 .* etalocm3 .* dy(3,:) .* ...
+ gfigfj(3,:) .* ...
+ (bp12 .* uloc(2,:)./etaloc(2,:) -...
+ bm12 .* uloc(1,:)./etaloc(1,:)) ... %% 3
+ );
git://git.creatis.insa-lyon.fr / CreaPhase.git / blobdiff