open TELEMAC-MASCARET The mathematically superior suite of solvers

Hi Pham!

I am trying to use drag force subroutine to simulate a wall. I get the following error after trying to run the cas.
DRAGFO: AREA OF ZONE EQUAL TO STOP 1

what is the meaning of the error? I tried to fix the polygon points and everything looks okay. I am wondering where to fix it now! I attached the screenshot. Do you have any thoughts?

It's indicate Area of zone equal to 0!
That's sounds clear!
You don't have any element (triangle) fully located in you polygon
regards

Sorry, I didn't get you. My polygon has mesh. Do you think I need to reduce the size of mesh to get rid of this problem? Any suggestions or idea about to fix it?

As the value of porosity is 0 in your area, this leads to element area equal to zero and then this message.
You cannot give nul value to mesh elements

Hi pilou1253,

I saw the dragfo file you modified where you used two polygons with 5 nodes for each. I am trying to modify for my polygon with 69 nodes. I attached the file here for

what I am trying. It gives an error. Can you please have a look and let me know why 69 nodes are not working?

Hi!

It is hard to understand what the error is if you don't give information about the error message itself.

However, I can see that you have not declared your variables correctly: you now use I69 in the QUASI-BUBBLE part, but there is only I4 that is declared:

INTEGER IELEM,I,I4,NSOM,DISCLIN

You should get a compilation error saying that I69 has no implicit type or smthg similar. Just replace I4 by I69 in the line above.
Beware that in the following line you still have I4 whereas it is not initialized before in the code Just replace it by I69.

IF(INPOLY(X69,Y69,XSOM,YSOM,NSOM)) AIRE = AIRE + T1%R(I4)

To use dragfo, keep in mind that you need to have VERTICAL STRUCTURES = YES in your cas file. This is what triggers the call to dragfo.

The subroutine you posted might be from an older version, I would suggest that you use the file from the version you are running.

Finally, I haven't worked with dragfo in years now, so I cannot garantee that what I suggest here is the way to go. But it should at least help you going further.

A last thing, if you have a complex polygon it might be a better idea to use PRIVATE VARIABLES (stored in the mesh file, see the manual and some examples using it like telemac2d/pluie) in order to identify which nodes drag should be applied to. If you are not familiar with fortran (which you should maybe work on if you are willing to use subroutines like dragfo...) it may not be the right advice to give you just now, but it is a far more convenient way to perform operations on given mesh areas / nodes. And it is not complicated, you just need to take the time to understand how it works.

Good luck!

Kind regards
PL

Hi PL,

Your last text helped me to identify the issue and that file worked finally. But I am trying to se another polygon in dragfo now and getting another error. I followed the way I worked before, then it was working. I attached the dragfo file and the error screenshot.

Hi
As it's clearly written in the message, your variable I84 has no implicit type this means you didn't declare it before using it...
Even Telemac is in Fortran, for safety programming reasons, it has been decided to avoid implicit fortran type, so you should declare all your variables.
Please take some times to learn , at least, the basics of fortran programming, this will help you a lot if you plan to modify user subroutines.
Regards

Hi c.coulet,


My bad, sorry I missed changing the I at the beginning of the file, I thought I changed it and defined it with corresponding number. It's working now.

Thanks,
Sumaiya

Hello, I defined the YSOM3(49), still getting the error "Unclassifiable statement at (1). I attached the dragfo file here. Everything else are okay, except YSOM(49), I defined it. What else I should check to fix it?