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 run a simple decay where the decay is depending on which depth the tracer are at.

I am trying to code the following equation: C(t+1)=C(t)*e^(-kt), the exact equation is attached. However, when I programme it I have written: S0TA= -TA*k and with this I get a small differens between my analytical calculations and TELEMAC, which indicates that something is wrong, fortranfile attached. Additionally I have added DEPTH according to post:

www.opentelemac.org/index.php/kunena/21-...-tracers-depth#28073

However, even if I only have a surface elevation on 0 and a depth on 10 m. I recieve a different answer for every node, which I do not understand as my depth is not varying. How is it that when I add DEPTH the concentration cahnges in every node, when it is constant over the whole mesh when I e.g. have put DEPTH=10.

Would be greatful for any help!

Best Regards

Hi,

I maybe understood your question in a different way because I assumed you wanted to have DEPTH at every node, ie. the depth of each 3D node. From your message above I understand that DEPTH should be total depth at a given 2D node location?

In that case you need to do:
DO I2D=1,NPOIN2
DEPTH = MAX(1.D-12,Z(I2D+NPOIN2*(NPLAN-1)) - Z(I2D))
DO IPLAN=1,NPLAN
I3D = I2D+NPOIN2*(IPLAN-1)
!continue here
ENDDO
ENDDO

I just saw that there already exists a BIEF structure called HN for depth, you might use that instead of my DEPTH suggested above.

Hope it helps!
PL