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Hello,

I want to modelize in a steady state a portion of a river which contains a weir.
I impose a constante discharge upstream (Q100) and a constant water level downstream.

I have a recurring error : Cross Section # 653 is dry. (653 is the before last section)
However, there is approximately a water depth of 2 m downstream. (The downstream level imposed is equal to the normal depth.)

I have tried to modify these parameters : mesh, planimetrage, time step, discharge coefficient, Strickler coefficient, but nothing works.

Does anyone know how to solve this problem ?

Thanks

Claire

Hi

Just as an idea, I think it's probably due to the weir in your reach.
As in steady state mode, the program start from the downstream water level and compute the water level on the upstream cross section according the discharge, in your case, it's look like the discharge take into account is 0 and the this generate a dry section.

Maybe you could try to test without the weir or to add your discharge in the description of the weir, it seems to me there is a place for this

Hope this helps

Thank you for your answer.
I'm going to try your solution.

I found in this case that if I put an important rugosity (k=10) for the two last meters of my reach, the model works.

Claire