• Re: initial surface elevation in mike 21

    Hi Vadlamudi Premkumar,

    oh, you put a pretty thin layer of water over an arbitrary terrain at the beginning. As soon as you start the model, the water will flow into the next nearby "whole" and form some puddles, some water might manage to flow out. This situation remains until water from the top rushing over the partly dry bathymetry.

    I suggest to start the model with the inital surface elevation which matches the inlet BC. In case that your inlet BC is varying, then I suggest a two step approach:
    Model Simulation 1:
    Use a constant initial surface elevation and keep the inlet boundary condition constant. Let it run long enough until you have a stable surface elevation in your entire model domain. Use the last timestep for your initial surface elevation of your final simulation
    Model Simulation 2 (final simulation):
    You can use the result of simulation 1 as a starting point (initial condition) for your final simulations. Change back to you original inlet condition and run your simulation.

    Hope this helps!

    Best regards
    Stefan
  • Re: difference between MIKE 21 and MIKE 21 fm?

    Hi Vadlamudo Premkumar,

    the answer for your question could depend on a lot of things: As one fundamental difference between MIKE 21 and MIKE 21 FM is the representation of the bathymetry, I would first look at the mesh in MIKE 21 FM:
    * Does it represent the key features of the bathymetry grid which was used in MIKE 21?
    * How is the model result when you use a finer mesh (say refine by factor 0.5)?

    Best regards
    Stefan
  • Re: initial surface elevation in mike 21

    Hi Vadlamudi Premkumar,

    are you still struggling with the surface elevation problem?
    (i) You know that you are free to set the initial surface elevation at any level you want, and you can do that by providing a constant value and a spatially varying surface elevation. Your bathymetric heights suggest that you are somewhere inland. So, to have any water in your model, for the initial surface elevation you would select a value larger than 3m. That should be easy, if you are sure that the vertical reference datum of your bathymetry is the same as your initial surface elevation.
    (ii) Then, I noted that your land value of 60m is 7m above the highest part of your model. The setting is ok as long as you will have no water travelling higher up than 60m.
    So in the case as you describe it, your initial surface elevation should be set somewhere between 3m and 60m.
    Best regards
    Stefan