154 lines
4.6 KiB
Matlab
154 lines
4.6 KiB
Matlab
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function [A,b,EdgesOfElements]=FemAssemble(node,Elements,domain,NbrEdge,lam0,epsilonr,mur,m)
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%矩形PML矩阵组装
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%m为PML阶次
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%物理参数
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k0=2*pi/lam0;
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E0=[1,1];
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%高斯积分点
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[xt,yt,pt,IntegralOrder]=GetGuassPoints(4);
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% IntegralOrder=4;
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% xt= [ 0.333333333333333,0.6,0.2,0.2 ];
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% yt= [ 0.3333333333333333,0.2,0.6,0.2 ];
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% pt= [ -0.28125,.260416666666,.260416666666,.260416666666 ];
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%网格处理
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NbrElement=max(size(Elements));
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el2no=Elements;
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n1=el2no([1 1 2],:);
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n2=el2no([2 3 3],:);
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el_ed2no_array=[n1(:) n2(:)];
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[Edges,~,EdgesOfElements]=unique(el_ed2no_array,'rows');
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NbrEdges=max(size(Edges));
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Dboudary=zeros(NbrEdge,2);
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%矩阵初始化
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Dof=NbrEdges;
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A=zeros(Dof,Dof);
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b=zeros(Dof,1);
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%狄利克雷边界
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NbrDboudary=0;
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%循环网格 组装矩阵
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for n=1:NbrElement
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%节点坐标
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x=zeros(3,1);y=zeros(3,1);l=zeros(3,1);
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x(1)=node(Elements(1,n),1);y(1)=node(Elements(1,n),2);
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x(2)=node(Elements(2,n),1);y(2)=node(Elements(2,n),2);
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x(3)=node(Elements(3,n),1);y(3)=node(Elements(3,n),2);
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l(1)=sqrt((x(1)-x(2))*(x(1)-x(2))+(y(1)-y(2))*(y(1)-y(2)));
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l(2)=sqrt((x(1)-x(3))*(x(1)-x(3))+(y(1)-y(3))*(y(1)-y(3)));
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l(3)=sqrt((x(3)-x(2))*(x(3)-x(2))+(y(3)-y(2))*(y(3)-y(2)));
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%雅可比矩阵
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Jac=zeros(3,3);
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Jac(1,1)=x(2)-x(1);Jac(1,2)=y(2)-y(1);
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Jac(2,1)=x(3)-x(1);Jac(2,2)=y(3)-y(1);Jac(3,3)=1;
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InvJac=inv(Jac);
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DetJac=abs(det(Jac));
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TJac=Jac'/DetJac;
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%小矩阵
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Et=zeros(3,3,IntegralOrder);curlEt=zeros(3,3,IntegralOrder);temp=zeros(3,1);
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for i=1:IntegralOrder
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for j=1:3
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[temp(1),temp(2)]=BF_Et(j,xt(i),yt(i));temp(3)=0;
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Et(j,:,i)=InvJac*temp*l(j);
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temp(3)=BF_curlEt(j,xt(i),yt(i));temp(1)=0;temp(2)=0;
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curlEt(j,:,i)=TJac*temp*l(j);
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end
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end
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if domain(n)==2
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xepsilonr=[epsilonr,0,0;0,epsilonr,0;0,0,epsilonr];
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xmur=[mur,0,0;0,mur,0;0,0,mur];
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averX=(x(1)+x(2)+x(3))/3;
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x0=0.5;
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d=0.5;
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R0=10000;
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Sx=1-1i*((averX-x0)/d)^m*(m+1)*R0/2/d/k0;
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Lambda=[1/Sx,0,0;0,Sx,0;0,0,Sx];
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xepsilonr=xepsilonr*Lambda;
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xmur=xmur*Lambda;
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invXmur=inv(xmur);
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elseif domain(n)==1
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xepsilonr=[epsilonr,0,0;0,epsilonr,0;0,0,epsilonr];
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xmur=[mur,0,0;0,mur,0;0,0,mur];
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invXmur=inv(xmur);
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end
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Sz=zeros(3,3);Tz=zeros(3,3);
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for i=1:3
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for j=1:3
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for k=1:IntegralOrder
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Sz(i,j)=Sz(i,j)+pt(k)*DetJac*dot(curlEt(i,:,k)',invXmur*curlEt(j,:,k)');
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Tz(i,j)=Tz(i,j)-pt(k)*DetJac*k0*k0*dot(Et(i,:,k)',xepsilonr*Et(j,:,k)');
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end
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end
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end
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for i=1:3
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for j=1:3
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A(EdgesOfElements((n-1)*3+i),EdgesOfElements((n-1)*3+j))=A(EdgesOfElements((n-1)*3+i),EdgesOfElements((n-1)*3+j))+Sz(i,j)+Tz(i,j);
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end
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end
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%边界处理
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%NbrDboudary 边界数
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%Dboudary n*2 1:网格 2：第几条边
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if (x(1)==-1)&&(x(2)==-1)
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NbrDboudary=NbrDboudary+1;
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Dboudary(NbrDboudary,1)=n;
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Dboudary(NbrDboudary,2)=1;
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elseif (x(1)==-1)&&(x(3)==-1)
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NbrDboudary=NbrDboudary+1;
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Dboudary(NbrDboudary,1)=n;
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Dboudary(NbrDboudary,2)=2;
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elseif (x(2)==-1)&&(x(3)==-1)
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NbrDboudary=NbrDboudary+1;
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Dboudary(NbrDboudary,1)=n;
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Dboudary(NbrDboudary,2)=3;
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end
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end
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%强加狄利克雷边界条件
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for n=1:NbrDboudary
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numEle=Dboudary(n,1);
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outNorm=[-1;0];
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if (Dboudary(n,2)==1)
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u=0.5;v=0;
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elseif (Dboudary(n,2)==2)
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u=0;v=0.5;
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elseif (Dboudary(n,2)==3)
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u=0.5;v=0.5;
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end
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%节点坐标
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x=zeros(3,1);y=zeros(3,1);l=zeros(3,1);
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x(1)=node(Elements(1,numEle),1);y(1)=node(Elements(1,numEle),2);
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x(2)=node(Elements(2,numEle),1);y(2)=node(Elements(2,numEle),2);
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x(3)=node(Elements(3,numEle),1);y(3)=node(Elements(3,numEle),2);
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l(1)=sqrt((x(1)-x(2))*(x(1)-x(2))+(y(1)-y(2))*(y(1)-y(2)));
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l(2)=sqrt((x(1)-x(3))*(x(1)-x(3))+(y(1)-y(3))*(y(1)-y(3)));
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l(3)=sqrt((x(3)-x(2))*(x(3)-x(2))+(y(3)-y(2))*(y(3)-y(2)));
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%雅可比矩阵
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Jac=zeros(3,3);
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Jac(1,1)=x(2)-x(1);Jac(1,2)=y(2)-y(1);
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Jac(2,1)=x(3)-x(1);Jac(2,2)=y(3)-y(1);Jac(3,3)=1;
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InvJac=inv(Jac);
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[temp(1),temp(2)]=BF_Et(Dboudary(n,2),u,v);temp(3)=0;
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tempEt=InvJac*temp*l(Dboudary(n,2));
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temp2=outNorm(1)*tempEt(2)-outNorm(2)*tempEt(1);
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numEdge=EdgesOfElements((Dboudary(n,1)-1)*3+Dboudary(n,2));
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temp1=outNorm(1)*E0(2)-outNorm(2)*E0(1);
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pp=temp1/temp2;
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b(numEdge)=pp;
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A(numEdge,:)=0;
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b(:)=b(:)-pp*A(:,numEdge);
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A(:,numEdge)=0;
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A(numEdge,numEdge)=1;
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end
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end |