open TELEMAC-MASCARET The mathematically superior suite of solvers

Dear all,

Greetings!
I was trying to closely study the horizontal acceleration of bed surface and how telemac can deal with this. so I am excited to know how the momentum equation is solved in telemac codes. I read the manuals and associated papers. for the close study how can I find out the code where the momentum equation is solved? which code should be studied for that?

thanks and regards

sidharth

Hello,

The key subroutines of TELEMAC-3D are TELEMAC3D, WAVE_EQUATION and CVDF3D.

Hope this helps,

Chi-Tuan

Dear Pham,
I found out the code dealing with the momentum equation is trisou.f in the source codes.


TERMS WITH FREE SURFACE GRADIENT (NODAL VALUES)
!
DO IPLAN = 1, NPLAN-1
!
DO I = 1, NPOIN2
IZ = (IPLAN-1)*NPOIN2+I
IZS = (NPLAN-1)*NPOIN2+I
A = GRAV*(DELTAR%R(IZ)-DELTAR%R(IZS))
!
CV1(IZ) = CV1(IZ) + A * GRADZSX%R(I)
CV2(IZ) = CV2(IZ) + A * GRADZSY%R(I)
ENDDO
!
ENDDO
!
ELSEIF(OPTFLO.EQ.2) THEN
!
YASEM3D = .FALSE.

in this code adding the horizontal acceleration along with the cv1 and cv2 doesn't make any changes to the result which are the source term. is there any way to make changes visible and the code to take the horizontal acceleration?

example of the horizontal acceleration value is .8609214E-04


thanks and regards
sidharth

Hello sidharth,

Hard to understand what you exactly want to do. Can you write the equation(s) you want to implement or exactly in which one and how you want to add the horizontal acceleration. Perhaps you can also indicate in the TELEMAC-3D theory guide where you want to do what you want.

Chi-Tuan

dear pham,

thanks for the response. what I want to do is add a horizontal acceleration
(seismic activity(m/s^2) ) in the model and to understand the changes that may happen like seiches formation. I found that this acceleration can be included in the non-hydrostatic momentum equation as a source term. The code that deals with the momentum equation is found to be in trisou.f in sour. so the acceleration can be included in the source terms which are cv1 and cv2. this part is mentioned in the previous message. so the equation that I need to modify is the non-hydrostatic momentum equation and adding the acceleration along with the equation in the x and Y directions.

CV1(IZ) = CV1(IZ) + A * GRADZSX%R(I)+(horizontal acceleration)
CV2(IZ) = CV2(IZ) + A * GRADZSY%R(I)=(horizontal acceleration)

this is the equation that I found to be altered to get a result. suggest to me if it is wrong, please.

thanks
sidharth

Dear Pham,

please clarify the doubt

thanks and regards
sidharth

Hello Sidharth,

Sorry for the delay, I forgot to answer and finally I had to check deeper what you described.

Your idea was good to implement in TRISOU subroutine. I think you did not get any effect because you added the horizontal acceleration at a wrong location.
Indeed, the sequence with GRADSX or Y is only done if ACTIVE_TEMP_SAL.OR.ACTIVE_SED is true, which may not be your case (LAW OF DENSITY = 0 without sediment, or = 5, or no tracer ?).
You should do the loop e.g. at the end of TRISOU subroutine with something like (I have not tested, there may be mistake(s)):

if ACCELERATION_X and ACCELERATION_Y are constant over the vertical or if it varies in 3D:

Hope this helps,

Chi-Tuan

Dear Pham,

thanks a lot for the effort that you took. I'll change accordingly and will update you regarding the results.


thanks and regards
Sidharth kr