Inverse heat transfer problem with Conjugate Gradient Method

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sebastien ROUQUETTE
Posts: 97
Joined: 05 Nov 2011, 16:50
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Location: Nimes, France

Inverse heat transfer problem with Conjugate Gradient Method

Post by sebastien ROUQUETTE »

Hello dear fellas...

i'm back.... i'm quite busy and my research leave is going to its end so.. i won't be here quite often but don't hesitate to PM me or email me.

This is the last program i did (and i checked it). From a writing point of view it is quite shortly detailed. i apologize.

Here is a compressed folder with my files: i use Elmer for defining my physical problem and then i wrote a python program with my optimization procedure based on the computation of the gradient with an adjoint problem (for who knows).

The aim is to identify/estimate an unknown heat flux with regards to the time evolution from given temperature measurements.
This objective is achieved through a minimization procedure that consists to minimize the quadratic temperature difference between measured and calculated (from a direct problem / elmer). Than the minimization method is based on the conjugate gradient iterative regularization method (short details in my pdf). this method requires to solve to other problems: adjoint and sensitivity. I defined the direct problem with elmer gui while i made two copies of it for defining directly in sif files the adjoint and sensitivity problems. The python file centralize the call of these 3 problems and the minimization technique is programmed inside two. You just have to run it (with python 2.7 of course on your pc).

Have fun!

If you have any questions.. contact me.

Regards and long life to Elmer!!!!
Attachments
inverse problem flow chart.pdf
(138.37 KiB) Downloaded 559 times
Inverse Heat Transfer Problem definiton.pdf
(745.59 KiB) Downloaded 583 times
IHTP_CGMethod.rar
(730.63 KiB) Downloaded 524 times
Last edited by sebastien ROUQUETTE on 22 Jun 2013, 12:11, edited 1 time in total.
Rouquette Sébastien
University of Montpellier / Mechanical and Civil Engineering Lab. / Welding Group
sebastien ROUQUETTE
Posts: 97
Joined: 05 Nov 2011, 16:50
Antispam: Yes
Location: Nimes, France

Re: Inverse heat transfer problem with Conjugate Gradient Method

Post by sebastien ROUQUETTE »

small erratum.
a small mistake in the IHTPwithCGM.py file (the first value of my vector heat flux had an error) and i corrected also an equation in my pdf file.
here are the right documents.
I repeat, the aim of this work is TO IDENTIFY AN UNKNOW HEAT FLUX (without a priori knowledge of its time distribution) as a function of time.
Good week end
Attachments
IHTP_CGMethod.rar
(148.38 KiB) Downloaded 648 times
Inverse Heat Transfer Problem definiton.pdf
(749.13 KiB) Downloaded 608 times
Rouquette Sébastien
University of Montpellier / Mechanical and Civil Engineering Lab. / Welding Group
sebastien ROUQUETTE
Posts: 97
Joined: 05 Nov 2011, 16:50
Antispam: Yes
Location: Nimes, France

Re: Inverse heat transfer problem with Conjugate Gradient Method

Post by sebastien ROUQUETTE »

well... i add a problem in one of my function in the main python file. I fixed it!

i attached the update files... it works under windows 7, python 2.7 and elmer v8.0

I recognize that this work should be more detailled... one day maybe.. when i will be retired (lol).

Regards
Sebastien
Attachments
IHTPelmer.rar
(834.64 KiB) Downloaded 391 times
Rouquette Sébastien
University of Montpellier / Mechanical and Civil Engineering Lab. / Welding Group
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