open TELEMAC-MASCARET The mathematically superior suite of solvers

Hello,

I have just started using Telemac3D so I have some doubts about setting the best parameters to reduce the simulation duration and increase the results quality. My geometry is a trapezoidal fish passage. My mesh density is 0.25m. I have attached my case file.
My main doubt is about the simulation beginning because a message saying that the maximum number of iterations is exceeded appears. How can I solve this problem?

Thanks in advance.

Abgail

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/ TELEMAC-3D - SAE - STP reduzido /
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/ COMPUTER INFORMATIONS
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GEOMETRY FILE = geo_mesh_025.slf
BOUNDARY CONDITIONS FILE = Mesh_025_BC.cli
2D RESULT FILE = 2D_results_SAE_STP_reduzido_mesh_025_Q_16.slf
3D RESULT FILE = 3D_results_SAE_STP_reduzido_mesh_025_Q_16.slf
PARALLEL PROCESSORS = 0
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/ GENERAL INFORMATIONS - OUTPUTS
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TITLE = 'SAE'
VARIABLES FOR 2D GRAPHIC PRINTOUTS = 'U,V,H,S,B'
VARIABLES FOR 3D GRAPHIC PRINTOUTS = 'Z,U,V,W,K'
GRAPHIC PRINTOUT PERIOD = 100
LISTING PRINTOUT PERIOD = 100
TIME STEP = 0.01
NUMBER OF TIME STEPS = 5000
MASS-BALANCE = YES
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/ INITIAL CONDITIONS
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COMPUTATION CONTINUED = NO
INITIAL CONDITIONS = 'CONSTANT DEPTH'
INITIAL DEPTH = 2.35
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/ BOUNDARY CONDITIONS
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PRESCRIBED FLOWRATES = 0.;16.
PRESCRIBED ELEVATIONS = 3.33;0.
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/ PHYSICAL PARAMETERS
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LAW OF BOTTOM FRICTION = 4
FRICTION COEFFICIENT FOR THE BOTTOM = 0.015
LAW OF FRICTION ON LATERAL BOUNDARIES = 0
HORIZONTAL TURBULENCE MODEL = 3
VERTICAL TURBULENCE MODEL = 3
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/ NUMERICAL PARAMETERS
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SCHEME FOR ADVECTION OF DEPTH = 5
SCHEME FOR ADVECTION OF K-EPSILON = 1
SCHEME FOR ADVECTION OF VELOCITIES = 1
SUPG OPTION = 0;0
IMPLICITATION FOR DEPTH = 1
IMPLICITATION FOR VELOCITIES = 1
MATRIX STORAGE = 3
FREE SURFACE GRADIENT COMPATIBILITY = 0.
MESH TRANSFORMATION = 1
NUMBER OF HORIZONTAL LEVELS = 5
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&FIN

Hello,

You are probably starting very rudely as you prescribe suddenly the discharge from a cold start. So I would not care about the maximum number of iterations if it disappears after a few iterations. I would even increase the time step because 0.01 is very small. However look at the result to see if there is no other problem in your model.

You can also, to start with, start with a turbulence model with constant viscosity on the horizontal (e.g. 0.1 or 1 m2/s) and mixing length on the vertical. I am not sure, depending on your domain, that the k-epsilon model will have time to set up a real turbulence (if the entrance is too close to the fish pass, you may see only the boundary conditions given on k and epsilon at the entrance).

Regards,

JMH