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Dear Users,

I am trying to recreate the strong stratified field with tides at an open boundary and water discharge at source that is based at bottom level on opposite closed boundary. So far I managed to create three stratified layers and tides coming into domain. But looks like source is not added as I am not getting rising plume of water when I look at cross section, in spite of large water discharge 30m3/s with speed x=2 and y=0. Could it be because I have multiple values of same tracers at different locations and system is confused. For example I have three different values for temperature (0.5; 1.5; 4) and salinity (25; 30; 34) in domain to create stratification but I also have different values of temperature (-0.29) and salinity (0.0) at source. I already have code written for tracers for layers only in fortran file but I am not sure how, and if I should, add the value of tracers at the source in fortran as well. I attached steering and fortran files for my case. Please advise. Thanks.

Kind Regards!

Violeta

Hello,

You should not have to add the source to the Fortran. Your case looks as you described, so I do not see an obvious error -- Would it be possible for you to zip all your file ans share the zip with us ?

Thanks.
Sébastien.

Hello Sebastien,


Thanks a mil, this one is sorted out too. I could not see the plume rise in my domain and I assumed that source does not contain any tracers, but I think it is because the domain is so big 120km and in comparison with this the plume is just not visible. When I run the same case but for small domain then I saw clearly the tracers values in my source. So I concluded it is just the matter of scale.

Thanks for your advise, just for my future queries, as I am not sure if we need to modify source soubrutine in fortran. Just one quick question on Values of Tracers at the sources. It is clear with Salinity, but not for Temperature value yet. In manual it is said that Value of Tracers at the Source means the concentration of the tracer in discharge. So if I want to enter "minus 1C" then I am not sure if in case for temperature it prescribes the correct value. In terms of Salinity it is clear, if I have 0 kg/m then it means the discharge is of pure water, but for temperature it is probably not a concentration but just a physical value. It is just a query, as I always had some doubts that I am doing right thing. I need to work with tracers and sources a lot. When you get a minute. Thanks a mil.

Kind Regards!

Violeta

Hello,

The source would be defined by a positive discharge -- in terms of volume of water. What is in the water is completely independent and can be a negative temperatures if you like -- it will be treated right. In fact, if you get you modify your density calculation a bit, you can even work in relative temperature around a given reference natural temperature. Same with salinity. This is what we usually do to look at excess ...

Hope this helps,
Sébastien.

Thank you Sebastien for clarification. Just one more (of too many, sorry) little questions in terms of density. We can get the Relative Density RHO output parameter. Is it just a variation of density from standard value of density specified in steering file, say "something" +/- from 1025? I am sorry, for such a stupid question but I come from different field and still have to learn a lot and fast! Thanks again.

Kind Regards!

Violeta

Hello,

Yes, the RHO0 (1025 for example) you mention is preferably an average of your case, so that the Boussinesq approximation is better. So it is not something like density of pure water at a given temperature (these latter reference densities are hardcoded). The relative density is (RHO-RHO0)/RHO0.

REgards,

Jean-Michel Hervouet

Thank you very much Jean-Michel, it is all clear to me now. Thanks a mil.

Kind Regards!

Violeta