Laurie Neilson-Welch

Great, thanks for the tip!

OK, thanks. Its running now, but slow.

When i model as saturated, I get a zero pressure isoline forming within the model (below the top boundary which is a ridge crest). Is that zero P isoline then an approximation of where the water table might be under actual phreatic aquifer conditions?  I will try with unsaturated conditions for comparison.
Thanks

I am trying to do some quick 2D simulations (vertical cross-sectinon) for a simple "hillslope" scenario with a phreatic surface.  The geology is layered with different K.  I have applied recharge flux boundary at the ground surface boundary and a seepage face condition (flux boundary constraint) along a hillslope at the right boundary  (no flow conditions are imposed at left and bottom of model). These models are not calibrated models, but simply preliminary models to look at sensitivity to some parameters.
I am trying to to do these quickly, therefore am specifying saturated flow conditions (even though it is not actually saturated above the water table), but the results still provide an approximation of the water table (pressure = 0 isoline) and i can look at resulting flow pathlines.

My question is....is the approximation for the unsaturated zone in 2D the same as the pseudo-unsaturated approach for 3D that is indicated in the While Papers?  It is not specifically indicated in the White Papers what the 2D approximation is.

Laurie

Hi,
Not sure if this helps for your problem, but I apply a constant flux boundary condition to the ground surface (top of cross-sectional model) and also assign a constraint (just click to add a constraint) that is equivalent to the ground surface elevation at that node. Then when the model reaches steady state, the top boundary conditions allow flux out of the model (discharge) at seepage areas where the water table intersects the ground surface, but recharge (flux in) along recharge zones.
Laurie

Hi,
I am simulating a simple 2D steady state model and trying to deterimine the groundwater pathline flux-weighted travel times for the model.
1. Is there a way to determine the flux rate that the pathlines represent using the "flux weighted option"?
2. When I use the "flux-weighted" option, the pathline traces do not, in some areas, correspond to the flux discharge results (budget).  In orther words, I have a lot of pathlines directed toward a zone that produces relatively low discharge according to the budget results. 
3. If I try reverse pathlines from discharge nodes, is there a way to truncate them at a line (i.e., the water table, P=0) - to get travel time through the saturated zone.

Laurie