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Hello,

I'm actually working with floats on telemac and I have some issues concerning calculation time.
I'm doing calculation on telemac 6.0 with over 2000 floats on my domain. My calculation time is very long, 7 hours with floats versus 37 min without for 5 days simulation.
I tried to minimise my mesh (from 25000 to 3000) but it didn't reduce time calculation much.
I don't know how telemac is managing floats on the code but if someone can explain me a bit more about it and how I can reduce my calcultation time it will be nice.

Thanks you very much

Julien

PS : On my temp file I have two huge file that are creating during calcultation : fort.8 and data_vit.dat, this file can go over 200go, my results seraphin float file is only 2000Mo.

Hello Julien,

The reason could be that with floats, the method of characteristics is called once per float, however it does only one point at a time so it should not be so heavy. In next version we'll try to have a single call for all floats. Actually this has been designed having in mind that we would have only a few floats.

However I see in your Post Scriptum that you generate huge files. fort.8 is the results file, I don't know what is data_vit.dat, I would rather look in that direction for explaining the overcost. What PERIOD FOR GRAPHIC PRINTOUTS do you use ?

With best regards,

Jean-Michel Hervouet

Hello Jean-Michel,

I removed all graphical output to gain time for the moment. This is maybe why the files are growing up so big.
I attach you my case file.

I was thinking that maybe a better solution could be a post result treatment, with matlab for example. But I don't know if this has been done in the past, do you think that can be a good solution ?

Sincerely

Julien

Hello,

A post-treatment is certainly possible, however the post-processor has to take into account variations in time, and not all the results will be available when there is a period of graphic printouts, so a bias would be introduced.

JMH