| Author | Message | ||
     Adrian Rozanski (mendoza81) Member Username: mendoza81 Post Number: 4 Registered: 04-2006 |
Hi. I`m solving the problem of computation of the effective elasticity parameters with assumption of periodic boundary conditions. In 2D everything is quite simple. In 3D I had a problem to set the periodic BCs. But I have already managed the problem. But now I would like to put the empty (void) sphere in the middle of the cube. I have no idea how to add the empty sphere to my input file. I have tried to make it many times, but no success. Have you got any ideas? Here is my input file: TITLE 'effective elasticity parameters - periodic boundary cond.' COORDINATES cartesian3 VARIABLES u v w SELECT painted errlim=1e-1 DEFINITIONS {R=0.05} A=30 G=30 Ex=1 Ey=0 Ez=0 Exy=0 Exz=0 Eyz=0 Sx=A*(Ex+Ey+Ez)+2*G*Ex+A*(dx(u)+dy(v)+dz(w))+2*G*dx(u) Sy=A*(Ex+Ey+Ez)+2*G*Ey+A*(dx(u)+dy(v)+dz(w))+2*G*dy(v) Sz=A*(Ex+Ey+Ez)+2*G*Ez+A*(dx(u)+dy(v)+dz(w))+2*G*dz(w) Txy=2*G*(Exy+0.5*(dx(v)+dy(u))) Txz=2*G*(Exz+0.5*(dx(w)+dz(u))) Tyz=2*G*(Eyz+0.5*(dy(w)+dz(v))) ! INITIAL VALUES EQUATIONS u: dx(Sx)+dy(Txy)+dz(Txz)=0 v: dx(Txy)+dy(Sy)+dz(Tyz)=0 w:dx(Txz)+dy(Tyz)+dz(Sz)=0 Periodic EXTRUSION SURFACE 'Bottom' z=-0.2 LAYER 'Underneath' SURFACE 'Can bottom' z=-0.19 LAYER 'Can' SURFACE 'Can Top' z=0.19 LAYER 'Above' SURFACE 'Top' z=0.2 CONSTRAINTS { Integral constraints } integral(u) = 0 integral(v) = 0 integral(w) = 0 BOUNDARIES LIMITED REGION 1 'box' LAYER 'UNDERNEATH' LAYER 'Above' START(-0.21,-0.21) NATURAL(u)=0 NATURAL(v)=0 NATURAL(w)=0 LINE TO (0.21,-0.21) NATURAL(u)=0 NATURAL(v)=0 NATURAL(w)=0 LINE TO (0.21,0.21) NATURAL(u)=0 NATURAL(v)=0 NATURAL(w)=0 LINE TO (-0.21, 0.21) NATURAL(u)=0 NATURAL(v)=0 NATURAL(w)=0 LINE TO CLOSE limited REGION 2 'mini box' layer 'can' START(-0.2,-0.2) NATURAL(u)=0 NATURAL(v)=0 NATURAL(w)=0 LINE TO (-0.19, -0.2) PERIODIC (x,y+0.4) LINE TO (0.19, -0.2) NATURAL(u)=0 NATURAL(v)=0 NATURAL(w)=0 LINE TO (0.2,-0.2) Periodic (x-0.4,y) LINE TO (0.2,0.2) NATURAL(u)=0 NATURAL(v)=0 NATURAL(w)=0 LINE TO (0.19, 0.2) LINE TO (-0.19, 0.2) NATURAL(u)=0 NATURAL(v)=0 NATURAL(w)=0 LINE TO (-0.2, 0.2) LINE TO CLOSE {LIMITED REGION 2 'empty sphere' LAYER 'can' void START (R,0) natural(u)=0 natural(v)=0 natural(w)=0 ARC(CENTER=0,0) ANGLE=360 TO CLOSE} PLOTS Grid(x,y,z) Grid(y,z) on x=0 CONTOUR(Sx) on y=0 CONTOUR(Sy) on y=0 CONTOUR(Sz) on y=0 CONTOUR(Txy) on y=0 CONTOUR(Txz) on y=0 CONTOUR(Tyz) on y=0 SUMMARY REPORT(Vol_Integral(Sx)/0.4^3) REPORT(Vol_Integral(Sy)/0.4^3) REPORT(Vol_Integral(Sz)/0.4^3) REPORT(Vol_Integral(Txy)/0.4^3) REPORT(Vol_Integral(Tyz)/0.4^3) REPORT(Vol_Integral(Txz)/0.4^3) END | ||
| Robert G. Nelson (rgnelson) Moderator Username: rgnelson Post Number: 584 Registered: 06-2003 |
The example problem "Samples | Misc | 3D_Domains | 3D_SphereBox.pde" constructs a void sphere inside a box. "2D_SphereBox.pde" shows a 2D analog of this problem using cylindrical geometry. |