• Saltwater Intrusion numerical dispersion

    Hello everyone

    I'm simulating a saltwater intrusion on a simple model which is set to be bounded by a hydraulic head BC by the western side and a saltwater head by the sea boundary (to the East). As far as regards mass transport boundaries, I have set a constant mass concentration BC by the sea boundary (35000 mg/l) and I am setting a saltwater inflow in the western boundary, only in the last two model slices (as my saltwater intrusion should cross all my model in the last two slices). However, when  starting simulating the mass transport I can't avoid oscillations and negatives values in the concentrations at the edge of the intrusion. Moreover, even if I set a saltwater inflow only in the last two slices, salt spreads all over the system by the end of the simulations. The mesh was set up to maintain a Peclet number of less than 1 given the dispersivity and I have also ensured that it had <5% obtuse triangles.  I've tried different upwinding techniques, but none of those remove the problem entirely either.  Also, I have tried a more gradual introduction of saltwater by varying the western concentration, but as soon as any saltwater enters the system negative values appear...

    Any suggestion that can help to avoid these problems?
  • Re: Problem Setting doubt

    thank you!!
  • Re: Problem Setting doubt

    Even if I set steady state conditions it doesn't let me change the transport state... the transport section always looks faded. May it be due to other problem settings?
    thank you
  • Re: Problem Setting doubt

    Thank you for the reply.
    The problem is that I can't change the transport state from problem setting as it is blocked (I have attached a picture to show you that)

  • Problem Setting doubt

    Hello everyone,

    for the most of you this could be very easy question, but I am first approaching feflow (7.0) these days working on a model built few years ago by other people and I cannot fully understand how it was built and how to proper set feflow in order to use it now. My question is:

    - why in problem setting cannot I modify the transport state? and also, why the projection section (always in problem class) disappears?

    Thank you  :)