Bondarie conditions problem

Log Out | Topics | Search Moderators | Register | Edit Profile

Author Message   Augusto (cdfx) Member Username: cdfx Post Number: 12 Registered: 04-2007 Posted on Thursday, July 19, 2007 - 01:12 pm:    Hi again Mr. Nelson I got a trouble in bondarie conditions in the code follow. Looking for xy plane the vectors in neighbour of both walls are small and the highest velocity is in the middle of tube, this is ok, but looking in xz plane in neighbours of both wall is very high. How I fix it? TITLE 'Tube Obtacle 3D' COORDINATES cartesian3 VARIABLES vx(1e-6) vy(1e-6) vz(1e-6) p SELECT { method controls } ngrid = 10.0 errlim = 0.001 stages = 1 regrid = off DEFINITIONS { parameter definitions } LIx = -2.1 LIy = 0.0 LSx = 3.1 LSy = 1.0 dens = 1.0 visc = 0.01 penalty = 1.0 Pin = 0.85 INITIAL VALUES vx = 0 vy = 0 vz = 0 p = Pin EQUATIONS ! vx: div(grad(vx)) - dx(p)/visc = dens*(vx*dx(vx) + vy*dy(vx) + vz*dz(vx))/visc ! vy: div(grad(vy)) - dy(p)/visc = dens*(vx*dx(vy) + vy*dy(vy) + vz*dz(vy))/visc ! vz: div(grad(vz)) - dz(p)/visc = dens*(vx*dx(vz) + vy*dy(vz) + vz*dz(vz))/visc vx: div(grad(vx)) - dx(p) = 0 vy: div(grad(vy)) - dy(p) = 0 vz: div(grad(vz)) - dz(p) = 0 p: div(grad(p)) = penalty * (dx(vx)+dy(vy)+dz(vz)) ! CONSTRAINTS { Integral constraints } EXTRUSION Z = 0.0, 0.1127016654, 0.4, 0.6, 0.887298335, 1.0 BOUNDARIES REGION 1 START(LIx, LIy) value(vx)=0 value(vy)=0 value(vz)=0 natural(p)=0 LINE TO (LSx, LIy) natural(vx)=0 natural(vy)=0 natural(vz)=0 value(p)=-Pin LINE TO (LSx, LSy) value(vx)=0 value(vy)=0 value(vz)=0 natural(p)=0 LINE TO (LIx, LSy) natural(vx)=0 natural(vy)=0 natural(vz)=0 value(p)=Pin LINE TO CLOSE LIMITED REGION 2 LAYER 1 VOID LAYER 5 VOID LAYER 6 VOID START (-2.0, 0.0) value(vx)=0 value(vy)=0 value(vz)=0 natural(p)=0 LINE TO (3.0, 0.0) LINE TO (3.0, 1.0) LINE TO (-2.0, 1.0) LINE TO CLOSE LIMITED REGION 3 LAYER 2 VOID LAYER 3 VOID LAYER 4 VOID LAYER 5 VOID START (-2.0, 0.0) LINE TO (3.0, 0.0) LINE TO (3.0, 0.1) value(vx)=0 value(vy)=0 value(vz)=0 natural(p)=0 LINE TO (-2.0, 0.1) LINE TO CLOSE START (-2.0, 0.9) value(vx)=0 value(vy)=0 value(vz)=0 natural(p)=0 LINE TO (3.0, 0.9) LINE TO (3.0, 1.0) LINE TO (-2.0, 1.0) LINE TO CLOSE LIMITED REGION 4 LAYER 3 VOID START (0.6, 0.1) value(vx)=0 value(vy)=0 value(vz)=0 natural(p)=0 LINE TO (0.8, 0.1) LINE TO (0.8, 0.9) LINE TO (0.6, 0.9) LINE TO CLOSE START (0.6 -2.0, 0.1) value(vx)=0 value(vy)=0 value(vz)=0 natural(p)=0 LINE TO (0.8 - 2.0, 0.1) TO (0.8 - 2.0, 0.9) TO (0.6 - 2.0, 0.9) TO CLOSE START (0.6 -1.0, 0.1) value(vx)=0 value(vy)=0 value(vz)=0 natural(p)=0 LINE TO (0.8 - 1.0, 0.1) TO (0.8 - 1.0, 0.9) TO (0.6 - 1.0, 0.9) TO CLOSE START (0.6 + 1.0, 0.1) value(vx)=0 value(vy)=0 value(vz)=0 natural(p)=0 LINE TO (0.8 + 1.0, 0.1) TO (0.8 + 1.0, 0.9) TO (0.6 + 1.0, 0.9) TO CLOSE START (0.6 + 2.0, 0.1) value(vx)=0 value(vy)=0 value(vz)=0 natural(p)=0 LINE TO (0.8 + 2.0, 0.1) TO (0.8 + 2.0, 0.9) TO (0.6 + 2.0, 0.9) TO CLOSE monitors GRID(x,y,z) VECTOR(vx,vy) zoom(0.0, 0.0, 1.0, 1.0) ON z = 0.1127016654 VECTOR(vx,vy) zoom(0.0, 0.0, 1.0, 1.0) ON z = 0.5 CONTOUR(vx) zoom(0.0, 0.0, 1.0, 1.0) ON z = 0.1127016654 CONTOUR(vx) zoom(0.0, 0.0, 1.0, 1.0) ON z = 0.5 vector(vx, vz) zoom(0.0, 0.0, 1.0, 1.0) ON y = 0.1127016654 vector(vx, vz) zoom(0.0, 0.0, 1.0, 1.0) ON y = 0.5 plots GRID(x,y,z) VECTOR(vx,vy) zoom(0.0, 0.0, 1.0, 1.0) ON z = 0.1127016654 VECTOR(vx,vy) zoom(0.0, 0.0, 1.0, 1.0) ON z = 0.5 CONTOUR(vx) zoom(0.0, 0.0, 1.0, 1.0) ON z = 0.1127016654 CONTOUR(vx) zoom(0.0, 0.0, 1.0, 1.0) ON z = 0.5 vector(vx, vz) zoom(0.0, 0.0, 1.0, 1.0) ON y = 0.1127016654 vector(vx, vz) zoom(0.0, 0.0, 1.0, 1.0) ON y = 0.5 end   Augusto (cdfx) Member Username: cdfx Post Number: 13 Registered: 04-2007 Posted on Thursday, July 19, 2007 - 02:32 pm:    Ops, I fixed using the SURFACE command Thanks!