open TELEMAC-MASCARET The mathematically superior suite of solvers

Hi, My name is Louise and at the moment I am doing my master thesis at Lund University where I am studying how degradation of bacteria can be modelled with help of TELEMAC. I am new to Telemac and really enjoy working with it. However have some thoughts concerning the subroutine SOURCE_TRAC.

I want to use and modify the part: UNIFORM DECAY RATE FOR TRACER NUMBER 1 (%ADR(1)). However, I do not understand how S0TA and S1TA is defined or calculated, and wonder if this could be clarified?

Furthermore, I wonder why both S1TA and S0TA are calculated and divided by two and why it is not only enough to calculated one of them?

I am very greatful for your help and looking forward to work more with Telemac.

Best Wishes
Louise

Hello Louise,

You can find a very useful description and examples of use of this subroutine thanks to the methods proposed by Sébastien Bourdan in this post:

www.opentelemac.org/index.php/kunena/21-...c-3d-computation#855

Good luck!

Best regards
PL från Stockholm

Thank you!

I have looked at the example www.opentelemac.org/index.php/kunena/21-...c-3d-computation#855.
However I do not really follow if the user by herself/himself needs to define the following or if it is defined by TELEMAC:

" The arrays you can play with are S1TA and S0TA.
- S0TA acts explicitely on the tracer value at the begining of the time step as follows:
TA = TA + S0TA ... + ADVECTION+DIFFUSION +...
- S1TA acts implicitely on the tracer value at the end of the time step as follows:
TA *( 1.-S1TA ) = TA + ... + ADVECTION+DIFFUSION"

Is it just enough to start with e.g. the following i.e. does TELEMAC have the equations for S0TA and S1TA already in the programme?

DO ITRAC=1,NTRAC
S0TA%ADR(ITRAC)%P%TYPR='0'
S1TA%ADR(ITRAC)%P%TYPR='0'
ENDDO

Hope you understand my question and sorry for the confusion.

Kind regards
Louise

Hello Louise

S0TA and S1TA are respectively explicit and implicit source terms for active tracers.
You can have a look on some examples already implemented in waqtel folder to understand the way to adapt it for your case. See for example subroutine calcs3d_o2.F in the folder Waqtel.

with my kind regards

Riadh

Hi again,

I have been looking in the source code to find where TA=TA+S0TA+advection... is calculated. I therefore wonder where TA is calculated (which file) in other words where I can find that TA=TA+S0TA+ advection....? I cannot find it in the files with name Source.

I hope my question makes sense.

Thanks alot!

Best Regards
Louise

Hi,

I have written a script that degrades E.coli, however it takes 1 second for it to degrade when I use my code and analytical it takes around 4 days. I am very new to programming and TELEMAC. I wonder if any mistakes can be seen in my code? Have I misunderstood how to write the code. The equation that the script is based on are attached and is a 1st order decay.

I have attached my files.
I would be greatful for your help.

Best regards
Louise