open TELEMAC-MASCARET The mathematically superior suite of solvers

Hi!

I do not have any experience working with Telemac2D, so I am really confused about choosing the best parameters to simulate my case. The geometry that I am working with is a vertical slot fishway. I have generated a coarse grid since I am just doing some tests.
Could you give me some tips about my steering file (attached)? I do not know if I have chosen the best solver and type of advection.

Thanks in advance.
Best regards,

Abgail

Hello,

Here are a few hints :

/ 0.1 seems small, try to have U*DX/DT around 1 to start with (it depends on your mesh size DX and your velocity U)
TIME STEP = 0.1
/ start with constant diffusivity and diffusivity 1., move to k-epsilon when it works
TURBULENCE MODEL = 1
VELOCITY DIFFUSIVITY = 1.
/ try wave equation first, you'll move to primitive and quadratic if you want very accurate results (much more expensive)
TREATMENT OF THE LINEAR SYSTEM = 2
SOLVER : 1
/ for inf-sup condition, I choose:
FREE SURFACE GRADIEN COMPATIBILITY: 0.7 (down to 0 if necessary)
/ and remove SUPG upwinding on depth
SUPG OPTION = 0;0
/ linear-linear discretisation to start with
DISCRETIZATIONS IN SPACE = 11;11
/ this is OK for steady state and quasi-steady
IMPLICITATION FOR DEPTH = 1.
IMPLICITATION FOR VELOCITY = 1.
/ segment storage gives faster matrix-vector product
MATRIX STORAGE = 3
/ conjugate gradient is OK for wave equation
SOLVER = 1
/ 1.E-6 would be better
SOLVER ACCURACY = 1.E-3


With best regards,

Jean-Michel Hervouet