lc = 0.5;dx = 0.05;dy = 0.05;dz = 1.0;nz = 80;Point(1) = {0.0,0.0,0.0,lc};Point(2) = {dx,0.0,0.0,lc};Point(3) = {dx,dy,0.0,lc};Point(4) = {0.0,dy,0.0,lc};Line(1) = {1,2};Line(2) = {2,3};Line(3) = {3,4};Line(4) = {4,1};Line Loop(5) = {1,2,3,4};Plane Surface(6) = {5};Transfinite Surface {6} = {1,4,3,2};Recombine Surface {6};out1[] = Extrude {0,0,dz/3} { Surface{6}; Layers { nz }; Recombine; }; out2[] = Extrude {0,0,dz/3} { Surface{28}; Layers { nz }; Recombine; }; out3[] = Extrude {0,0,dz/3} { Surface{50}; Layers { nz }; Recombine; }; // InletPhysical Surface(30) = {6};// OutletPhysical Surface(32) = {72};// Box volumePhysical Volume (35) = {out1[1], out3[1]};Physical Volume (36) = {out2[1]};