open TELEMAC-MASCARET The mathematically superior suite of solvers

Dear all
I'm a user of telemac2D, version v6p2. I'm simulating the flow in a urban zone (2D on the street, channel, river,...). Inside of computational domain, there are some islands (not inundation, the block building for example). I suppose that the rainfall is in all my computational domain. I would like to know how does the telemac2D consider the rainfall on the island where there don't have the network 2D. My question also is that Telemac2D always consider the rainfall on this surface?. If not, how can I do to put in to the rainfall in this island ? Thank you very much for your helps and suggestions.
Best regards

Thong NGUYEN
HCMUT, Viet Nam

Hello Thong,

Yes, the program will not consider the rainfall on the islands if they are not meshed. The first thing we can think of is adding a source point nearby the building, or increasing the rainfall so that the right quantity falls, but this is not local. Another idea is to modify locally the rainfall on points around the island. This can be done in subroutine PROSOU where array PLUIE%R is built. You will see that in case of tidal flats PLUIE%R is not a constant.

With best regards,

Jean-Michel Hervouet

Dear Mr. J. M. Hervouet
Thank you very much for your quickly response. I will apply your suggestion in my work.
One more time, thank you so much.
Best regards
Thong NGUYEN
HCMUT, Viet Nam

Dear Mr. J. M. Hervouet,
In general case, with your suggestion, it seem so difficult to determine the number node which will be used in subroutine PROSOU? (network change!). In the case where the point source will be used, the area of each island isn't easily to calculate with software Blue Kenue and provide to Telemac2D!
Best regards
Thong NGUYEN
HCMUT, Viet Nam

Hello,

If you add the rainfall to boundary points, you can rely on the array BOUNDARY_COLOUR%I which is the original boundary point number (last line of the boundary conditions file), you can also rely on the coordinates, in all cases it implies a loop with tests.

For the area of islands, if you can define them as a list of points of the contour, there is an easy formula, the area is half the sum of all x(i)*y(i+1)-x(i+1)*y(i), i being all the nodes of the contour.

With best regards,

Jean-Michel Hervouet

Hi Thong,

You can indeed get the areas of islands in Blue Kenue.

Steps...
1. Select the Mesh in the WorkSpace.
2. "Tools->T3Mesh->Extract Edges" will create a lineSet of all islands and the mesh outline.

Then:
1. View the lineSet.
2. Double click on an island to get the perimeter and area.

Or:
1. Select the lineSet in the WorkSpace
2. "<right-click>->Show Attribute Table" generates a table of perimeters and areas of all closed-lines/islands.

NOTE: I just noticed that the line IDs reported when double clicking start counting at 1 and the line IDs in the table start counting at 0 so there is an offset.
(THIS IS A BUG WHICH WILL BE FIXED IN THE NEXT RELEASE)

Hope this helps... Martin

Dear Mr. J. M. Hervouet and Martin,
Thank you very much for your helps.
Best regards
Thong NGUYEN
HCMUT Viet Nam