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Hello,

I simulated nutrient emissions (passive, so far) in "my" bay.
I set all necessary KEYWORDS in my cas file (e.g. VALUE OF THE TRACERS AT THE SOURCES, DISCHARGE VALUE OF THE TRACERS AT THE SOURCES). I have 14 layers in my mesh. Does it mean that at the initial time step the value of the tracer chosen in the cas file will be equal in all layers over the vertical (constant over the vertical)? Or is the punctual source just set on the surface layer?
From Blue Kenue is not so clear to distinguish it.

Thank you.

Best

(cas file attached)

Hello,

I cannot presently check but I think that you must give the coordinates of the sources, abscissae, ordinates AND elevations, then for every point the program will look for the nearest point in the mesh and the release will be done there.

With best regards,

Jean-Michel Hervouet

Dear Jean-Michel Hervouet,

I tried using the TRACER VERTICAL PROFILE as default and also with option 2, but already at the first time steps I have the tracer only in the bottom layer or until the nearest one. I want to try also with the user defined option, but it wonders me that I do not have a constant vertical profile if I leave the deafault option.

Thank you in advance.

Best regards

Hi

I'm afraid you're mixing 2 different things
Tracer vertical profile is for the tracer at the boundaries
Sources are always punctual at the nearest node of the source location

In your computation, except if there is already some tracer in the previous run or if you define it manually, the initial value is given by the steering file.
As you source discharge is small and the concentration low, the tracer is diluted in the volume surrounding the source node.
If the mesh is quite large, the concentration in the result will be very low...

Hope this helps

Thanks for the suggestion, it helps a lot. You are right. I am following different cases and I got confused.
Is there maybe a KEYWORD where I can set the value of the tracer at the source depending on the elevation?
The fact is that I am simulating nutrient emissions from a net-cage aquaculture system in a lake, where velocities are very low. The emissions should be nearer the surface than the bottom. Also, I assumed that the discharge is 1 m3/s just to give a very small value, because I have there no well or sink.
Best Regards

Hi

As I said, a source is related to a node so there is no keyword to give the value of tracer according the elevation except is you create many source point at different elevation.

If there is low velocities in the lake, this also means the layers should move too much along the vertical axis.
If you don't like to add discharge, I think you could also by modifying the code just impose the tracer value at some nodes (I'm not fully sure this will works)
The main problem of this solution will be you didn't control the quantity of tracer you will add to the system...
Probably Jean-Michel could give you a better advise but you should wait a little bit...
Regards