open TELEMAC-MASCARET The mathematically superior suite of solvers

Hello to all

I’m studying a sediment transport in a rectangular channel (with a sand layer of 9 cm)
I run Telemac2D coupling with Sisyphe, but here I find a strange result: normally we should have a bed level evolution between -0.01 and 0.004 m but I find a big value!!
Also I noted a changes in the bathymetry ( I use the key FINITE VOLUMES:YES, normally , non-erodible bed!!
Any suggestion please

thank you
jean

Hello Jean,

some general hints:
- instead of MEAN DIAMETER OF THE SEDIMENT use SEDIMENT DIAMETERS (what I know the first one is old and depreciated)
- if you have only one grain size, then the concept of active/inactive layer treatment is useless
- use the noerod.f subroutine to specify the non-erodible bed level.
- what are your boundary conditions and initial conditions for the sediment transport simulation?

Best regards,
Clemens

Hi

thank yopu so much for your reply but I have a question about noerod.f how to fixe the rigid bed by noerod.f I find this:

CALL OV( 'X=Y+C ',ZR,ZF,ZF,-100.D0,NPOIN)
I didn't understand, why (-100) and in my case how I choose this number, can someone explain me that or give me an exemple I'm so sorry for this question??
why in the version V6p2 we have this formula:
CALL OV( 'X= C ',ZR,ZF,ZF,-100.D0,NPOIN)
best regard
Jean

Hello,

OV is a subroutine for vector operations.
CALL OV( 'X=Y+C ',ZR,ZF,ZF,-100.D0,NPOIN) means that at every node (NPOIN) the height of the non erodible bed ZR is defined as ZF (bottom level) - 100.0 m. So you can modify this line to your needs if the specification is simple, e.g. give another value instead of -100.D0. If you want different zones of non-erodible bed than you could use e.g. the inpoly function.

Yes, in prior versions the absolute height of the non erodible bed was defined as ZR = -100.0 m. This was a little bit ambigous and has been corrected by the developers according to the history notes in the noerod.f subroutine.

Best regards,
Clemens

Hello Konsonaut

thank you so much for the reply

best regards
Jean