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Solver output window and model convergence

  • 2019年12月23日
  • jervfjellet

Convergence to steady state?
I have run some tests with steady flow. At the upstream boundary the inflow is constant with time. At the down stream boundary the water level is constant.

I had expected that the flow situation should stabilize after some time. After some initial unsteadiness the model should converge and the flow pattern should become constant. No changes from one time step to the next.

However, even after relative long run times the flow pattern, velocities etc. keep changing. Questions:
1. Should I expect the model to “converge” / gain a steady state.
2. What can I do to improve convergence?
3. Does the model output some kind of stability / convergence information?
4. How can I find the flow through the downstream boundary (to check when Qin = Qout)?

Lars J


  1. UC-1h より:

    If you want to converge your calculations, I suggest using Upwind Scheme.
    Upwind Scheme is less likely to calculatiton failure and more stable than CIP method.

    You can check the convergence infomation in the output log.
    Time, Discarge, Downstream water level, Convergence info, Output timing.
    The smaller Convergence infomation is converged.

    You cannot check the discharge directly on iric.
    You can only calculate by yourself using ExportCSV.


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