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#1 2017-03-15 16:35:47

mabr
Member
Registered: 2017-03-08
Posts: 3

Temperature dependent heat transfer coefficient

Hello!

I am trying to define boundary condition with heat transfer coefficient and sink temperature. If I use operator AFFE_CHAR_THER and define constant heat transfer coefficient and sink temperature, I get the desired output. For temperature dependent heat transfer coefficient I tried to use AFFE_CHAR_THER_F, but it seems to me that in this case heat transfer coefficient can be dependent only of time, and not temperature.

If I define functions for heat transfer coefficient and sink temperature dependent of time

HTC=DEFI_FONCTION(
                   NOM_PARA='INST',
                   NOM_RESU='COEF_H',
                   VALE=(1.0 ,400.0 ,
                         10.0 ,500.0 ,),
                   PROL_DROITE='LINEAIRE',
                      PROL_GAUCHE='LINEAIRE',
                   );

Text=DEFI_FONCTION(
                   NOM_PARA='INST',
                   NOM_RESU=' TEMP',
                   VALE=(1 ,5000.0 ),
                   PROL_DROITE='CONSTANT',
                      PROL_GAUCHE='CONSTANT',
                   );

LOADING=AFFE_CHAR_THER_F(MODELE=MODEL,                       
                       ECHANGE=_F(  GROUP_MA = 'Edge_1',  COEF_H = HTC,
                                    TEMP_EXT = Text),);

THER=THER_NON_LINE(MODELE=MODEL,
                   CHAM_MATER=MATFIELD,
                   ETAT_INIT=_F(    VALE = 100.0),
                    INCREMENT=_F(   LIST_INST = LR8),
                    NEWTON=_F(ITER_LINE_MAXI=5,
                                 REAC_ITER=1,
                                 RESI_LINE_RELA=1,),
                   EXCIT=_F(CHARGE=LOADING),);

Code_aster returns no error, but if i give heat transfer coefficient function value NOM_PARA='TEMP' instead of NOM_PARA='INST', i get error:

! Error during the interpolation of the function  HTC.           !
   !                                                                !
   ! The parameters necessary are:                                  !
   !  TEMP                                                          !
   !                                                                !
   ! The provided parameters are:                                   !
   !  X Y INST                                                      !

It seems to me that it is not possible in CodeAster to define temperature dependence. I don't believe that this could be a mesh problem. Or am I wrong?

Thanks for any response.

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#2 2017-03-15 21:04:25

stephaneberger
Member
From: Strasbourg (France)
Registered: 2012-10-15
Posts: 70

Re: Temperature dependent heat transfer coefficient

Hi,

It's not possible to do what you want to do.

see this post http://code-aster.org/forum2/viewtopic.php?id=20816

stephane

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#3 2017-03-17 14:29:28

sébastien meunier
Member
From: EDF Lab Les Renardières
Registered: 2007-12-02
Posts: 287

Re: Temperature dependent heat transfer coefficient

Hello,

I think it is possible by using calc_fonc_interp. I do not remember details but documentation states it is possible and I have a colleague who achieved this task.

Regards,


Sébastien Meunier - EDF Lab Les Renardières

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