lx =
ly =
r =
lc = 
Point (1) = {0 ,0 ,0, lc}; // centre du trou
Point (2) = {0 ,r ,0 ,lc};
Point (3) = {0 ,ly ,0 ,lc};
Point (4) = {lx ,ly ,0 ,lc};
Point (5) = {lx ,0 ,0 ,lc};
Point (6) = {r ,0 ,0 ,lc};
Line (1) = {5 ,6}; // bas
Line (2) = {4 ,5}; // droite
Line (3) = {3 ,4}; // haut
Line (4) = {2 ,3}; // gauche
Circle (5) = {6 ,1 ,2};
Line Loop (6) = {1 ,2 ,3 ,4 ,5};
Plane Surface(7)={6};
Physical Line ("bas") = {5 ,6}; // bas
Physical Line ("droite") = {4 ,5}; // droite
Physical Line ("haut") = {3 ,4}; // haut
Physical Line ("gauche") = {2 ,3}; // gauche
Physical Surface(1) ={7};