BASEMENTBasic Simulation Environment for computation of environmental flow and natural hazard simulationLaboratory of Hydraulics, Hydrology and Glaciology (VAW)ETH Zurich |
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respected sir ,
i am running software basement for my coupling 1D network and geting this error
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*!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Error !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*
*******************************************************************************
-> Newton-iteration in calculateZ(A) for cross section 'st4_3' failed after
reaching max #iteration (1000).
Requested A = 1.48703e+030
Current z = 0
A-Anew = 1000
[z0,z1] = [57.074, 67.34]
[A0,A1] = [0, 225.775]
Your minimum_water_depth might be the problem, try to vary your
minimum_water_depth
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*!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Error !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*
*******************************************************************************
how to solve this ?
regardz
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Hi Adnan
Do you start your simulation with dry initial conditions?
Try to get reasonable initial conditions for all your 1-D subdomains first!
Hope this helps!
Cheers, Lukas
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yes i choose dry condtions.
ok but what will be the suitable conditions to run ?
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Please try to produce reasonable initial condition by using e.g. initial condition of type 'backwater'.
Furthermore check your parameters in HYDRAULICS -> PARAMETERS -> SECTION_COMPUTATION, you might adapt for example 'min_interval', 'max_interval' (for type 'table') or change
to type 'iteration'.
Hope this helps!
cheers, Lukas
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Dear Lukas ,
my conditions are
as below
INITIAL {
type = dry
}
PARAMETER {
minimum_water_depth = 0.0001
SECTION_COMPUTATION {
type = iteration
precision = 0.0001
}
}
}
i am doing an urban flood modelling project in whch i am taking streets as channel and coupling them
for every channel my condition is same as above ,
regards
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further more my model is oneway 1d couple and
other thing is if you can make me a simple tutorial/run file on using the initial conditions other than dry that is ( backwater & continue ) would be appreciated .
thanks
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Hi Adnan
Did you try
INITIAL {
type = backwater
}
PARAMETER {
minimum_water_depth = 0.0001
SECTION_COMPUTATION {
type = table
max_interval= 0.001
min_interval= 0.0001
}
}
}
try to play with the parameters 'max_interval' and 'min_interval' for all your subdomains, even with dry initial condition.
hope this helps!
cheers, Lukas
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thanx for the help i will look into it and will tell you what i get from the above conditions
regards
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choosing the backwater option ask for parameters q_out and wse .
i tried with your specified conditions and i was able to run basement after a little tweaking in x-sections but after i change my hydrographs bsement starts giving the above errors again ,
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If you were able to run basement for a constant hydrograph, then use the result file '_restart' as a initial condition (continue) for all your future model runs!
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dear Lukas ,
i did as what you have said , but now i am having this issue
-> OpenMP: Computation is executed sequentially
-> Domain: Starting time loop
-> Domain: Run Time of the simulation= 0 sec
-> Domain: Finished simulation.
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Try to use 'start_time' = 0.0 or increase your simulation run in the TIMESTEP block.
Hope this helps!
cheers, lukas
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i have run the basement on constant hydro graph of 30 m^3/s and set them as initial condition for my other hydrograph . basement runs
but 30 cumecs is too much value . so i now want to run for 1 0r 0.5 cumecs but again i am having the same problem .
the other thing is how much the minimum water depth value should be used ? i am using 0.0001 default
also i am using cfl value 0.6 . is it ok ?
regards
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With such small discharges you will have very small flow depths, which will cause problems.
Try to use type table for section computation with very small intervalls.
With CFL=0.6 you will have quite high numerical diffusion.
As you can read in the help button of the GUI, the CFL should be as close as possible to 1.0.
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thanx lukas for the quick replies
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