open TELEMAC-MASCARET The mathematically superior suite of solvers

Dear all

I'd like to make a geometry file and add a variable named 'RIGID BED' to change the rigid bed elevation.However,after the simulation the rigid bed level is still -100m.
If there is something run in my geometry file?

thanks for your help

Dear Jason,

the rigid bed variable will not be read from the geometry file but from the previous computation file. If you have no restart the noerod subroutine is called and set your rigid bed to bottom - 100. One way is to create a sedimentological previous computation file with rigid bed. Another way is to modify fonstr.f so that the rigid bed is read from the sisyphe geometry file.
Below I have copy a code part which you can add in fonstr.f. This code part is from an old version (v6 or v7). So you have to adapt it to your version. The same procedure is done for the geometry in fonstr.f. You only need to change ZF (bottom variable) to ZR (rigid bed variable) and modify the names of course.

Best regards,
Rebekka


!RK
print*,'fonstr aus sisy fortran file'
C
IF(LNG.EQ.1) CALL FIND_IN_SEL(ZR,'FOND RIGIDE ',NGEO,W,OK,
* TIME=BID)
IF(LNG.EQ.2) CALL FIND_IN_SEL(ZR,'RIGID BED ',NGEO,W,OK,
* TIME=BID)

! print*,'find_in_sel',w,ok,zr%R(1)
C CAS D'UNE GEOMETRIE AVEC UNE LANGUE ETRANGERE
IF(.NOT.OK.AND.LNG.EQ.1) THEN
CALL FIND_IN_SEL(ZR,'RIGID BED ',NGEO,W,OK,TIME=BID)
ENDIF
IF(.NOT.OK.AND.LNG.EQ.2) THEN
CALL FIND_IN_SEL(ZR,'FOND RIGIDE ',NGEO,W,OK,TIME=BID)
ENDIF
IF(OK) THEN
IF(LNG.EQ.1) WRITE(LU,55)
IF(LNG.EQ.2) WRITE(LU,56)
55 FORMAT(1X,'FONSTR : FOND RIGIDE LUS DANS',/,
* 1X,' LE FICHIER DE GEOMETRIE')
56 FORMAT(1X,'FONSTR : RIGID BED READ IN THE',/,
* 1X,' GEOMETRY FILE')
ENDIF
!RK END

Hi Jason.

A complement to Rebekka's post:
In the latest TELEMAC versions, the proper way is to modify a "user-prefixed" subroutine file, instead of the core one. In this case "user_noerod.f".

I attach a custom "user_noerod.f" written to do what you want. It was inspired from subroutine FONSTR. It is created in 2019 so it might need some adapting as well.



Notice the "T2D_FILES(T2DGEO)%LU". This was specified to read from the geometry file set in Telemac2D because GAIA was coupled with T2D. With T3D you need to adapt accordingly. I also believe that this can work with Sisyphe as well.

Costas

I am trying to create an area where all the nodes are non-erodable. From reading the forum, my understanding is- I need to add a new variable to the GEO from add variable option, where the source will be BOTTOM and the variable name will be FOND. Am I correct? Then I need to create a NOER file from where the nodes which I don't want to be eroded will be (bed elevation-100). Then I need to copy the NOER file into the FOND variable in bluekenue using map object. Then just I will run the fortran file in CAS. Is that what I need to do? Please correct me where I am wrong step-wise. Thanks.

The standard name for the non-erodable variable is
RIGID BED M

I cannot see the RIGID BED variable in the drop-down menu in GEO add variable option. Do I just create this name?
And the other steps I mentioned here correct?

The variable should have the level of the non-erodable layer. If this is at the surface layer of the bed, the value should be equal to the BOTTOM layer. If the bottom is erodable, the RIGID BED varaible should be lower than bottom.

Hi, I have attached my GEO file and the nodes (rigid bed nodes) which will not erode. Now my question is- Do I need to create a NOER file with all bed elevation nodes and change the elevation for the rigid bed nodes to (Bed elevation - 100) and the rest of the elevation values will be unchanged?

If I add rigid bed variable to GEO, will it have any effect on to flow model? If I create a hotstart of flow model without defining rigid bed and later can I use the hotstart for a sediment model defining the rigid bed into GEO?

Hello all,
In recent telemac versions (at least vp3r2) the user can also define 'non erodible bed' by means of sediment thickness. One can add variable "LAYER1 THICKNES" (note the double space and one 'S', it is not a typo) to the geometry file and GAIA would take it from there.
Best Regards,
Costas

Edit:
My bad, still need to define a means to read the variable from the geometry file. I will upload a working fortran file.