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Hi Mathieu,
I used your procedure in making different domain and different friction coefficient. But, i am not able to understand the last step. For examble, if i have ten region with ten friction coefficients how do i specify this in cas file.

thanks,
Sathish

Hi Sathish,

The easiest way to do this is to use Bluekenue.

Here are the steps :

1. Draw a closed line (polygon) around the mesh region that you want to apply a friction coeff.

2. Once done, a pop up window will appear asking you what elevation you want to set the closed line. Instead of entering an elevation, just enter the friction coefficient you want for that mesh region.

3. Select your mesh as selafin object under the workspace. Right click -- > Add variable. Add variable of BOTTOM FRICTION.

4. Now select the mesh variable that you just created and then go on tools menu under "Map object". Select the closed line that you made at step 1 and 2 and map it on the mesh variable.


Hope it's more clear

Mathieu

Hi Mathieu,

I can able to do all the above procedure. My doubt is, when the domain having a single friction coefficient we used to give FRICTION COEFFICIENT = 'Value' in steering file. What should i do for multiple region in a single domain????

thanks in advance

Hi,

Create a lineset with multiple polygons.
using <lineset context menu> ->Add Closed Line

Each line/polygon can have a different value.

Alternatively you could use the "2D Interpolator" as a source
for mapping friction. (It's no just for bathymetry)

Hope this helps... Martin

Hi Sathish,

If I remember correctly, the value in the steering file will be applied to region of your mesh not defined by the polygon closed lines.

You should however verify this. I'm not 100% sure.


Mathieu

Hi,

Thanks to Serrer and Mathiew

I tried with three different region with three friction coefficient but i gave FRICTION COEFFICIENT is 50 in steering file which does not give any results. Herewith i attached the files. Please have a look at it and give your suggestion to resolve this.





thanks,
Sathish

Hi,

I use Fudaa to define different friction regions in my mesh, but I guess it functions the same way in Blue Kenue.

Be aware that as soon as you have a BOTTOM FRICTION object in your geometry file, the value of the keyword FRICTION COEFFICIENT is NOT USED by Telemac. Which means that you need to define friction regions for your entire mesh in order to be consistent, to avoid having areas with default values.

Good luck!
PL

Hi PL,

Thanks for your reply.

Actually i am trying to define the friction coefficient like the way you mentioned but, i am not able to fix it. Please tell me that how do i assign the friction coefficient values for different region in a cas file.

thanks,
Sathish

Hi

As soon as your friction coefficient varies in space, you must define it in the geometry file. You CAN'T do that in the cas file (have a look at the manual).

In the cas file you should give the keyword for friction law. I think you must also have FRICTION COEFFICIENT = 'value' otherwise you have an error message, but this keyword is overruled by the friction values contained in your geometry file (i.e. 'value' IS NOT USED by the program!!).

That's all you need to do.

Good luck
PL

Hi Sathish,

You must not have 3 BOTTOM FRICTION objects in your geometry file. You must include all 3 friction coefficient in the same BOTTOM FRICTION mesh...

It's probably the reason it's not working.


Mathieu