Is the flow only supposed to be in the z-direction in this example? On Wed, Jun 4, 2008 at 9:57 AM, asreeve <[EMAIL PROTECTED]> wrote: > Daniel and Jonathan, > > I've rerun the problem we worked on last Wednesday, and I'm having the same > problems that I described at that time. I'm not sure if the script I'm > running is different than the one we worked on at NIST, or if we were a > little premature in thinking the problem was fixed. > > I'm still having problems with the convection term in my 3-D model. The flow > conditions should be at steady state, but some cells divergence of the > fluxes are far enough from zero to cause problems with the solution. If I've > set the problem up correctly, the max and min concentration values should be > 1700 and 180, respectively. > > To confirm that the divergence is the problem, I added another > ImplicitSource to the equation (line 82) based on the cell divergence (to > add a flux assigned the cell conc, recirculate the water in the cell back > into the cell and balancing the flux). This produces concentrations that are > within a sensible range, but I've not checked this against an analytic > solution. > > I'd note I get these problems what I add heterogeneity to the mesh by > varying the permeability of cells. Things work fine when all the flow is in > the Z direction (along the axis of the extruded tube), and not diverted in > the x or y directions (where the grid is not orthogonal). > > > Andy > > ---------------------- > Andrew Reeve > Dept. of Earth Science > University of Maine > Orono, ME 04469 > >
-- Daniel Wheeler
