open TELEMAC-MASCARET The mathematically superior suite of solvers

Hello all,
We are working on a water quality modelling. We have
BINARY DATABASE 1 FOR TIDE =h_tpxo9.v1

BINARY DATABASE 2 FOR TIDE =u_tpxo9.v1
And as no Hycom data was available for the offshore boundary, the initial condition was considered constant value for tracers.
INITIAL VALUES OF TRACERS = 15;28
PRESCRIBED TRACERS VALUES = 15;28
the only salinity and temperature profiles we have are inside the project domain as circled in the picture(file number 1) and please see the condim file to see how we programmed our zones( file numver 2).
Also to force the initial condition even we considered same initial condition for tracer at the area upstream of the project domain.(Please see file number 3, green area has programmed to have the same initial stratification)
We used the mash transformation equal to 3 (see file number 4) as we found in the forum that it works better when we have stratification in the model.
Please also see the CAS file( File number 5)

Also we set the accuracy for diffusion of tracer = 10^-10.
with all the set up we tested so far, after a few hours the salinity and temperature profiles reached to equilibrium constant value.
We tried K-E and Mixing length horizontal Turbulence model. Also in order to reduce the mixing of tracers over the water column we also we try to set the scheme for diffusion of tracers keyword equal to zero
SCHEME FOR DIFFUSION OF TRACERS = 0
The 0 value at each keyword cancels the diffusion, whereas the 1 value (default value) leads to the implicit calculation of diffusion.
But with all these tests still we could not keep Salinity and temperature stratification same as the initial condition.Please see the result file(File number 6) for temperature and salinity which shows all layers reach to the equilibrium over few hours.
also please see the field temperature and salinity profile(file number = 7)

Your attention is very much appreciated to give us an idea how to keep tracers stratification same as implemented initial conditions.

Thanks in advance,
Sanaz

Dear Sanaz,


I suggest you to use:
1)
2) You can try without turbulence model (constant (molecular) viscosity) instead of SCHEME FOR DIFFUSION OF TRACERS = 0.

3) You also can reduce your time step and add more layers.

Best regards,
J

PS: please it is simple for all to remove unused keywords in your STEERING FILE!!