bugborder.edp

FreeFem++可以生成高质量的有限元网格。可以用于流体力学

verbosity=0;
real x0=0.0, x1=1.5;
real y0=0.0, y1=2.0;
real xx0=0.5, xx1=1.;
real yy0=0.5, yy1=1.;
int acc,ref, i;
real sH;
ref=10;

border a( t= x0,x1){ x= t ; y= y0; label=1; };
border b( t= y0,y1){ x= x0; y= t ; label=2; };
border c( t= x0,x1){ x= t ; y= y1; label=3; };
border d( t= y0,y1){ x= x1; y= t ; label=4; };
border aa( t= xx0,xx1){ x= t ; y= yy0; label=1; };
border bb( t= yy0,yy1){ x= xx0; y= t ; label=2; };
border cc( t= xx0,xx1){ x= t ; y= yy1; label=3; };
border dd( t= yy0,yy1){ x= xx1; y= t ; label=4; };

//cout << "enter accuracy = ";
//cin >> acc;
acc=0;
// Creation des maillages grossier et fin

//mesh TH=square(ref,ref,[x0+(x1-x0)*x,y0+(y1-y0)*y]);

mesh TH = buildmesh( a(10) + b(-10) + c(-10) + d(+10)
                    +aa(-10) + bb(+10) + cc(+10) + dd(-10) );
plot(TH,wait=1);
end;

{ //    hole 
real pi=4.0*atan(1);
border a(t=0,2*pi){ x=cos(t); y=sin(t);label=1;};
border b(t=0,2*pi){ x=0.3+0.3*cos(t); y=0.3*sin(t);label=2;};
mesh Thwithouthole= buildmesh(a(50)+b(+30));
mesh Thwithhole   = buildmesh(a(50)+b(-30));
plot(Thwithouthole,wait=1,ps="Thwithouthole.eps");
plot(Thwithhole,wait=1,ps="Thwithhole.eps");
}