Denim Umeshkumar Anajwala

Please take a look at the seepage face boundary condition. For details see the documentation (e.g. users manual).

How about increasing K for the part of the model domain that gets excavated? That's the second change we normally make, but is that even required/suggested?

Thanks, Chris

In Addition: the file has to be finished by an END statement. Also it is is possible to write the new trp file directly as tab separated file if the filename (with the ending .trp) is set within quotation marks.
e.g.:
1.0 1.0 2.4
2.0 4.4 4.1
3.0 5.1 4.2
END

William

I'm afraid some of those formats I've never heard about. I had no experience with GIS myself when I started at AquaResource a couple of years ago, but can't imagine a work life without it anymore. Should you ever consider looking into it, I strongly recommend Manifold. It's extremely inexpensive (starting at $245), comes with powerful capabilities, and is one of the most straightforward software packages I've ever seen.

So, going back to your initial question about transmissivities. I take it, you generate nodal transmissivities and then contour those in Surfer? Would it help to have a shape file with polygons showing elemental transmissivities (as described in my previous post)?

Cheers, Chris

Hey,

the way to specify a well in FeFlow is to assign type 4 BC's at nodes that fall within your filter (screened segment) of your well. Don't set BC's, where the well is cased.

We typically set the pumping rate at the bottom node, and 0 at all other adjacent nodes as you suggested in your posting. That way, if the upper nodes of the well start to fall dry due to the pumping, the BC value is still specified at a saturated node. Whether that is necessary for the calculations to be correct, I'm not sure, but it just adds a little bit of peace of mind. The actual pumping from the different layers along the filter will be determined during the flow simulation and is based on the transmissivities (as far as I know).

Hope that helps, Chris.

Hey William,

just out of curiousity: How do you plot your maps (without GIS)? In Surfer? What types of input format do you use for that?

Chris

Chris

I can confirm that one can specify time-varying K data using the t-list and power funtions. I have used such a feature to simulate the intallation of a slurry wall and to simulate the excavation of contaminated (native soil) with clean fill (of differing hydraulic properties). As for the rest of your questions, I do not know the answer.

Dwaine

Hey,

I haven't used the budget analyzer for heat fluxes, but what you described sounds familiar from flow budgets. As far as I know, FeFlow calculates flows into a multi-layer well based on the layers' transmissivities, but only reports the flow total in the water budget at the node where a BC value <> 0 was specified. During the simulation, however, that total is spread along the well segment, so that ALL BC nodes along the well receive some portion of the total flow. Can someone confirm that??? It is confusing though ...

Chris.

As an update: I talked to the FeFlow developers: there is currently no API function available to return the "area of an element"  :(

It's on my wish list though ... Chris

This is an excellent comment!!! I was wondering about this exact same thing recently, when I was using a PreSimulation IFM to update K data. If I understand the process correctly, this is how FeFlow generates a DAC file:

1) Copy data (incl. K's) from FEM to DAC file
2) Run simulation (next time step)
3) APPEND simulated heads (and velo's) to the DAC file
    (for those time steps specified)

That should explain why K-data manipulated through an IFM during the simulation is not stored in the DAC file. Only simulated heads get appended to the DAC. Correct?

[Edited: Ops, I just noticed that I had made a similar comment before under "IfmBudgetComponents - area flux"  ;D]

Now I'm wondering: Is it possible in FeFlow to specify time-varying K data? I've never tried that (and can't really think about a reason why I ever would), but a quick peek at the FeFlow help suggests, that this is possible by either using a T-List or power-functions. How would that be reflected in the DAC file and how would the Budget Analyzer consider this time-varying K-data in it's computations? ???

Chris