open TELEMAC-MASCARET The mathematically superior suite of solvers

Hi guys,

I have an issue and it would be great if you can help.

I am modeling a case in which I think side wall friction might be an important factor as depth/Width of the channel is not small.

So, I tried to switch on the side wall friction option. The details of the turbulence models used and friction option chosen are.

VERTICAL TURBULENCE MODEL = 2 / Prandtl's Mixing Length model
HORIZONTAL TURBULENCE MODEL = 1 / Constant coefficient
COEFFICIENT FOR HORIZONTAL DIFFUSION OF VELOCITIES = 1.E-3
/
LAW OF BOTTOM FRICTION = 2 / Chezy
FRICTION COEFFICIENT FOR THE BOTTOM = 39.5
LAW OF FRICTION ON LATERAL BOUNDARIES = 1 / there are only two options 0 and 1 (Nikr)
FRICTION COEFFICIENT FOR LATERAL SOLID BOUNDARIES = 35 /(I also tried 60, the default)

The program starts to Run but within the first few iterations a error message is recorded in the xxxx.sh.oyyyy file:

TBORD: UNKNOWN FRICTION ON BOUNDARIES : 1

PLANTE: PROGRAM STOPPED AFTER AN ERROR


The error says, "UNKNOWN FRICTION ON BOUNDARIES : 1" but what I have used is what is recommended in the TELEMAC-3D operating manual "v5p8_gb"

Please shed some light on this issue and please suggest the solution.

thank you

Hello,

You are right, the documentation is not correct. According to the dictionary, the laws are 0,1,2,3,4,5

0:no friction
2,3,4 : coefficient taken in the boundary conditions file
5: Nikuradse

and in TBORD you see that in the rough regime case, only 0 or 5 is possible, so the documentation should say : 0 or 5.

Thanks for pointing out this, we are about to issue a new user manual.

With best regards,

Jean-Michel Hervouet

Thanks a lot,

yes the dictionary does provide the correct information.

best regards

Som

Hello,

I've found there's a friction calculation subroutine for telemac2d "friction_calc.f", but for telemac3d I couldn't find the corresponding one. Could you please help me if there is one subroutine for telemac3d to calculate friction coefficient/terms.
Thanks in advance.

Best regards.
Robinson

Hello,

In Telempac-3D, a call to COEFRO (telemac2d library) does the friction coefficient CF and subroutine TFOND does U*.

Regards,

JMH