open TELEMAC-MASCARET The mathematically superior suite of solvers

Hello Everyone,

I am setting up a model in Black Sea area and my area interest of near Odessa. I am trying to calibrate my model and the friction coefficient and velocity diffusivity are not affecting the model at all. The point I analysis the result has a depth about - 8m. However I analysis spatially and in some area, it is only changing up to "mm" scale.My mesh resolution is too low. Is that also be a reason? Or should I reduce the time step? Please suggest me any solution or reason. Thank you very much for your time.

Best Regards,
Sone

Hello

There is not enough inputs about your model to identify the problem. what are your forcing factors (wind, tide, coriolis, etc).
If you have tide, you have a set of keywords that can be used for calibration. Please see user manual for that.
with my kind regards

Riadh

Thank you so much for your help. I do not have measured data so I am trying to calibrate with data from "Tide Forecast" which is only astronomical tides. Thus, I am not considering wind but I considered Coriolis force and tide generating force and use TPXO for boundary conditions. I calibrate with "Tidal coefficient" but the result is not very good. I will also attach the steering file and everything. Please kindly help me if there is any way to calibrate this. Thank you very much.

Hi Sone,

I suspect that there is a projection setting issue with your model, as you turned on "SPHERICAL COORDINATES" and the mesh you uploaded seems to be build in projected coordinates. Moreover, the LATITUDE OF ORIGIN POINT isn't 0 in your case.

With TPXO database, I advise you to work either:
- in real geographic coordinates (mesh coordinates in degrees)
- or a mesh in UTM projection (SPHERICAL COORDINATES = NO, SPATIAL PROJECTION TYPE = 2, GEOGRAPHIC SYSTEM = 2, and ZONE NUMBER IN GEOGRAPHIC SYSTEM = 36, I think in your case)

(with a slight preference for the 2nd solution).


Note also that:
- the activation of TIDE GENERATING FORCE is useless here, your model domain isn't large enough and you already use TPXO data at boundary of your domain to consider tide
- there is a regional database for the Black Sea, maybe more accurate than the global one: volkov.oce.orst.edu/tides/med.html

I hope it helps.

Regards,
Laurent

Hi Leballeur,

Thank you so much for your reply. I will try to follow your suggestion. One more quick question, could I change the projection of my mesh in some software or should I set up the model form the beginning. Thank you so much for your help.

Best,
Sone

Hi Sone,

You don't have to rebuild your mesh from the beginning.
Several scripts already exist (in python or matlab for instance) which allow you to:
- read and extract the old coordinates of your mesh,
- replace the old by the new coordinates and write your new mesh.

Between these 2 steps, you just have to change the projection of the coordinates with a dedicated tool.

Regards,
Laurent

Thank you so much for your help.