Hi,<br>
<br>
I am trying to create a layered sphere (with the inner sphere and outer
spherical layer to be assigned different material properties). 
I've created the  .geo file below, but I'm not sure whether the
resultant tetrahedral mesh actually connects the interface between the
inner and outer spherical layers and matches the faces of the adjoining
tetrahedra. Can anyone advise me on this?<br>
<br>
Julian<br>
<br>
// sphere_layer.geo<br>
// sphere of radius r1, centered on the origin<br>
// with an outer spherical layer of radius r2<br>
<br>
lc=0.2;<br>
r1=0.3;<br>
r2=0.6;<br>
<br>
// inner semicircle points<br>
Point(1) = {0,0,0,lc};<br>
Point(2) = {0,0,-r1,lc};<br>
Point(3) = {0,-r1,0,lc};<br>
Point(4) = {0,0,r1,lc};<br>
<br>
// outer semicircle points<br>
Point(5) = {0,0,-r2,lc};<br>
Point(6) = {0,-r2,0,lc};<br>
Point(7) = {0,0,r2,lc};<br>
<br>
// inner semicircle lines<br>
Line(1) = {1,2};<br>
Circle(2) = {2,1,3};<br>
Circle(3) = {3,1,4};<br>
Line(4) = {4,1};<br>
<br>
// outer semicircular slice lines<br>
Line(5) = {2,5};<br>
Circle(6) = {5,1,6};<br>
Circle(7) = {6,1,7};<br>
Line(8) = {7,4};<br>
<br>
// inner semi-circle line loop<br>
Line Loop(9) = {1,2,3,4};<br>
// outer slice line loop<br>
Line Loop(10) = {5,6,7,8,-3,-2};<br>
<br>
// inner semi-circular plane<br>
Plane Surface(12) = {9};<br>
// outer layer plane<br>
Plane Surface(13) = {10};<br>
<br>
// extrude inner semi-circle to get inner sphere<br>
v1[] = Extrude Surface {12, {0.0,0.0,1.0}, {0.0,0.0,0.0},2*Pi/3};;<br>
v2[] = Extrude Surface {v1[0], {0.0,0.0,1.0}, {0.0,0.0,0.0},2*Pi/3};;<br>
v3[] = Extrude Surface {v2[0], {0.0,0.0,1.0}, {0.0,0.0,0.0},2*Pi/3};;<br>
<br>
// extrude outer slice to get outer spherical layer<br>
v4[] = Extrude Surface {13, {0.0,0.0,1.0}, {0.0,0.0,0.0},2*Pi/3};;<br>
v5[] = Extrude Surface {v4[0], {0.0,0.0,1.0}, {0.0,0.0,0.0},2*Pi/3};;<br>
v6[] = Extrude Surface {v5[0], {0.0,0.0,1.0}, {0.0,0.0,0.0},2*Pi/3};;<br>
<br>
<br>
//assign volume number 1 to outer layer<br>
Physical Volume(1) = {v4[1],v5[1],v6[1]};<br>
<br>
// assign volume number 2 to inner sphere<br>
Physical Volume(2) = {v1[1],v2[1],v3[1]};<br>
<br>