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I am new to Telemac and BlueKenue so my apologies if this question seems basic.

I would like to set an initial water level for half of my mesh (simulating a dam break). From my understanding of the boundary conditions in BlueKenue, there is a limitation that you can only add a boundary condition along the boundary or shoreline of the mesh.

Is it possible to setup an initial depth and apply it to a portion of the mesh? If so how?

Thank you!

Hi Karen,

With BlueKenue, you can pre-process your bathymetric data and build an associated mesh. From this mesh, it also allows you to generate a file (called "BOUNDARY CONDITIONS FILE") defining the kind of hydrodynamical conditions you want to impose on the different boundaries of your mesh (see section 4.2 of Telemac2D user manual for more details).
Then, you have to defined your own initial conditions with Telemac2D. Several possibilities are described in section 4.1 of the same user manual. For an initial water level on a part of your domain, I think you have first to have in your steering file: INITIAL CONDITIONS = 'PARTICULAR'
and then code in the subroutine condin.f so as to find the nodes where you want to impose the desired water elevation.

Hope it helps.
Laurent

Hi
There is some example with this kind of situation (look into malpasset test case for example).
You could also build your initial free surface (in BK for example) and save it as a selafin file which could then be use as a previous result...

Regards

Hello Laurent,

I am working with 3 boundaries, with variable initial free surface elevation. I have set "initial conditions: particular" and I am attempting to modify CONDIM.f. Please see if the modification (attached) is appropriate. Also, is the condim file setting the water depth or free surface elevation.

Free surface |Water depth (FreeSurface - bottom)
Boundary 1: 5.97 m |1.62 m
Boundary 2: 13.16 m |-3.15 m
Boundary 3: 6.28 m |2.05 m

*****************
USER INPUT :
CALL OS('X=C ' ,X=H,C=4.35D0)
CALL OS('X=C ' ,X=H,C=16.31D0)
CALL OS('X=C ' ,X=H,C=4.23D0)
IF(LNG.EQ.1) WRITE(LU,10)
IF(LNG.EQ.2) WRITE(LU,11)
10 FORMAT(1X,'CONDIM : AVEC DES CONDITIONS INITIALES PARTICULIERES'
& ,/,1X,' VOUS DEVEZ MODIFIER CONDIM')
11 FORMAT(1X,'CONDIM : WITH SPECIAL INITIAL CONDITIONS'
& ,/,1X,' YOU HAVE TO MODIFY CONDIM')
CALL PLANTE(1)
STOP
! END OF SPECIAL INITIAL CONDITIONS
! END OF USER INPUT
*****************

Regards,
Chijioke.

Hi,

To prescribe constant water depth or free surface, I think you don't need to program. Did you first try to set the prescribed values in your steering file as follow ?

INITIAL CONDITIONS = 'CONSTANT DEPTH'
INITIAL DEPTH = depth_bnd_1 ; depth_bnd_2 ; depth_bnd_3

or

INITIAL CONDITIONS = 'CONSTANT ELEVATION'
INITIAL ELEVATION = elevation_bnd_1 ; elevation_bnd_2 ; elevation_bnd_3

Regards,
Laurent

Hi Laurent,

I have not tried any of these methods,. Based on all the examples I have come across, I thought "Initial depth/elevation" takes only one value. I will implement them now.

Regards,
Chijioke.

You are right. These keywords only accept one value as it refers to the whole domain, and not to the boundaries.
You should use PRESCRIBED ELEVATIONS instead.

Regards,
Laurent

Hi

You're right!
Initial Elevation or Initial depth could only take one value.
I think Laurent made a mistake with the prescribed elevation at boundaries...

Nevertheless, your modification are not appropriate.
Just calling 3 times OS leads to giving the value of the latest call to H...

in my opinion, the easiest way for you to build an initial condition is to use Blue Kenue. Create a variable named FREE SURFACE. Create some support values like line or points with the right elevation and use the interpolator to map them on the Free surface.
Check the results and iterate if necessary

Finally you could use the created variable as an initial condition if you use the previous computational file

Hope this helps

Hi,

Thank you.

I have not done a lot of work with BlueKenue but it does sound easier and I will explore it.

Regarding working with BlueKenue, does this mean only the specified points (in this case my boundary points) will have values while the other points (inside the domain) will be 0 m.

Regards,
Chijioke.

Hello,

I have tried employing Bluekenue. However, when I run the simulation, I get an error message:

"SUITE_SERAFIN : DIFFERENT MESH (OR WRONG STANDARD)

Regards,
Chijioke