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Hello,

I use telemac in order to make tidal model.
I extract harmonic constants from NAO and TPXO and make my own harmonic constant file by referring to www.opentelemac.org/downloads/TRAINING%2...ation_maree_v6p2.pdf.
Because I want to apply only 4 constituents, M2,K1,O1,S2 in my model with 3 open boundaries.
However, tidal force does not impose all open boundary nodes. Tidal force impose to only first two nodes. Please advise how to fix attached harmonic constant file to impose tidal force to all the open boundary nodes.

I attached harmonic constant file.

Thank you.

Hello,

For TPXO database, you don't need to use your own harmonic file. You can directly use TIDAL DATA BASE = 2 and provide the BINARY DATABASEs 1-2 FOR TIDE. But you'll have to code something to only consider the 4 constituents you mention.

If you want to use your own harmonic file, the format of the file is not correct. In the header, you have to provide as follow:
- 1st line: NUMBER OF THE TIDAL BOUNDARIES (3 or 4 in your case, in don't really know)
- following lines (as long as there are tidal boundaries): THE FIRST AND LAST INDICES OF THE OPEN LIQUID BOUNDARY WITH TIDE TO PRESCRIBE for each tidal boundary
- and then:
"Total number of tidal boundary points" "number of constituents" "M"

Then you have to write for each of your 4 constituents, the amplitude and phase for the whole tidal boundary points.


I attach an example with 61 tidal constituents and 2 tidal boundaries. The first boundary goes from boundary points 1 to 55, and the second one from 4721 to 4778, for a total number of tidal boundary points of 113 = (55-1+1) + (4778-4721+1).



I hope it helps.

Regards,
Laurent

Dear Leballeur,

Thank you for your helping.
I modified harmonic file by referring to your advise and to simulate my model with new harmonic file. Tidal force impose to all the open boundary nodes properly.

Thank you.
Minjae Lee.

Dear Leballeur:
Thank you for your explanation. Your reply has helped me a lot. I still have a question to ask you. do you know the mean of ‘cote du fond interpolée’ in the harmonic constants file for the JMJ database?

Hi,

It is the bottom elevation interpolated on the node.

Regards,
Laurent

thank you，sir.
I also want to ask a question, how should the tide data file(ASCII DATABASE FOR TIDE) be obtained

Hi,

This data file is mainly used with the JMJ database (TIDAL DATA BASE = 1), only available over French coasts.
I don't know if there is an existing script to write it, you can write it by yourself from another tidal database, but it advise you to directly use the "HARMONIC CONSTANTS FILE" instead with TIDAL DATA BASE = 3. Its format is slightly different.

You can have a look at the "TIDE" example provided with Telemac2D distribution.

Regards,
Laurent

Thank you, you mean you can calculate the tides just by harmonic constant file? I'm just using Harmonic Constant File but the tidal wave is a regular sine wave

Yes, that's it.
If you have just a sinusoidal wave, it means that you only have one tidal constant in your harmonic file. You should add other ones.

Regards,
Laurent

Hello, This answer has already solved some of my questions. However, I still have some doubts. I hope you can help me with them:

1. Originally the post refer to the "harmonic constants from NAO". Are there several ways to create my own harmonic constants file?

2. In the examples shared by the user and Laurent in this post, I noticed both are using latitde and longitude (in degrees) for the points position. If I am setting my model in transverse mercator, should I still use Lat and long (deg)?

3. I obtained the constituents in the location of a gauging-station. Is there a way to obtain the constituents for all the nodes in my boundary Cond. lines, from the constituents I have for the station point? Like a shifting formula?

4. I am familiar with the TPXO method, is there a way to use TPXO option and modify the constituents values (amplitudes and phases) with the ones I have from the data analysis?

5. In the document simulation_maree_v6p2 the COMODO tools are recommended to create the harmonic constants file, but the procedure is not detailed. Is there any place containing some guidelines, examples or documentation about this tool? And is it advisable to use this tool nowadays or better try to construct the harmonic file manually?

Thank you. Regards,
Jorge