open TELEMAC-MASCARET The mathematically superior suite of solvers

Dear all,

I've two small questions on the source code of telemac3d:

- What is the difference between the implicit and explicit deposition flux? If I'm not mistaken the explicit deposition flux is just the multiplication of the implicit flux with the sediment concentration, but why is this distinction made in the source code?

Also, are the arrays ATABOF and BTABOF the only two carrying information on erosion and deposition terms to be given as a source/sink term to the adv-diff equation solver or am I missing something?

- In the subroutine SOURCE_TRAC, what's the difference between the explicit and implicit source terms?

Thank you very much in advance!

Shandro

Hello,

Generally the negative terms are better treated as implicit (with a yet unknown concentration in the formula), otherwise there is a risk that the concentraion becomes negative. Positive terms can remain explicit (the known concentration at time t(n) may be used). This is why seen from the sediment transport equation, deposition is implicit and erosion explicit. The implicit part ends up in ATABOF and the explicit part in BTABOF. In source_trac the user may decide if she or he wants a source term in explicit or implicit form.

With best regards,

Jean-Michel Hervouet