Question to Nonlinear Static Syntax

Hi,

I'm using a adapted .comm file from Kees Wouters plasticity tutorial.
The calculation with this .comm file works proper.
A displacement for the top face of a body ("Ftop") which is fixed at the bottom ("Fbot") is given.

I try to replace the displacement with a force or a pressure.
When I calculate the body the calculation is not aborted by an error but no results and no project_nameres.med file is written.


The Syntax of the .comm file that works:

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
DEBUT();


pmesh=LIRE_MAILLAGE(FORMAT='MED',);

pmode=AFFE_MODELE(MAILLAGE=pmesh,
AFFE=_F(TOUT='OUI',
PHENOMENE='MECANIQUE',
MODELISATION='3D',),);

#Material properties
Sigmaeps=DEFI_FONCTION(NOM_PARA='EPSI',
VALE=(0.0016, 330,
0.0032, 350,
0.0064, 367,
0.0128, 387,
0.0200, 401,
0.0270, 410,
0.0400, 420,
0.0700, 437,
0.1000, 450,
0.1500, 473,
0.2000, 490,
0.3000, 510,),
INTERPOL='LIN',PROL_DROITE='LINEAIRE',PROL_GAUCHE='EXCLU',);

#define plastic behaviour of steel by Traction
steel=DEFI_MATERIAU(ELAS=_F(E=2.1e5,NU=0.27,),
TRACTION=_F(SIGM=Sigmaeps,),);

pmesh=MODI_MAILLAGE(reuse =pmesh,
MAILLAGE=pmesh,
ORIE_PEAU_3D=_F(GROUP_MA=('Ftop',),),);

matprops=AFFE_MATERIAU(MAILLAGE=pmesh,AFFE=_F(TOUT='OUI',MATER=steel,),);


LoadFix=AFFE_CHAR_MECA(MODELE=pmode,
FACE_IMPO=(_F(GROUP_MA='Fbot',DZ=0.0,DX = 0.0, DY = 0.0,),),);



t1 = 10;

t2 = (2 * t1);

t3 = (3 * t1);

t4 = (4 * t1);


#NBT = Number of time steps
NBT = t1;
#T_END = end time
T_END = t4;

disp = 0.0750
LoadPres=AFFE_CHAR_MECA(MODELE=pmode,
FACE_IMPO=(_F(GROUP_MA='Ftop',DX=disp,),),);

ramp=DEFI_FONCTION(NOM_PARA='INST',
VALE=(0.0,0.0,
t1,1.0,
t2,2.0,
t3,0.0,
t4,-1.0,
),PROL_DROITE='EXCLU',PROL_GAUCHE='EXCLU',TITRE='ramp',);

time=DEFI_LIST_REEL(DEBUT=0.,
INTERVALLE=(_F(JUSQU_A=t1,
NOMBRE=NBT,),
_F(JUSQU_A=t2,
NOMBRE=NBT,),
_F(JUSQU_A=t3,
NOMBRE=NBT,),
_F(JUSQU_A=t4,
NOMBRE=NBT,),),TITRE='time',);


deflist = DEFI_LIST_INST(DEFI_LIST=_F(METHODE ='AUTO',
LIST_INST = time,
PAS_MINI = 0.0005),)


Presul=STAT_NON_LINE(MODELE=pmode,
CHAM_MATER=matprops,
EXCIT=(_F(CHARGE=LoadFix,),
_F(CHARGE=LoadPres,FONC_MULT=ramp,),),
COMP_INCR=_F(RELATION='VMIS_ISOT_TRAC',
DEFORMATION='SIMO_MIEHE',
TOUT='OUI',),
INCREMENT=_F(LIST_INST= deflist,), #time,
NEWTON=_F(REAC_INCR=1,
MATRICE='TANGENTE',
REAC_ITER=1,),
CONVERGENCE=_F(ITER_GLOB_MAXI=20,),
ARCHIVAGE=_F(PAS_ARCH=1,),);


Presul=CALC_ELEM(reuse = Presul,
INFO=2,
TYPE_OPTION='TOUTES',
OPTION=('SIEF_ELNO_ELGA','EPSI_ELNO_DEPL','EPSP_ELNO','EQUI_ELNO_SIGM','EQUI_ELNO_EPSI','EPSP_ELGA','EPSI_ELGA_DEPL','EPSG_ELNO_DEPL','EPSG_ELGA_DEPL'), RESULTAT=Presul,);




# calculate nodal equivalents and reaction forces
Presul=CALC_NO(reuse =Presul,
RESULTAT=Presul,
OPTION= ('SIEF_NOEU_ELGA','FORC_NODA','REAC_NODA',),);

#Write Results to MED file
# displacements DEPL (x, y and z component)
# vonMisses stresses EQUI_ELNO_SIGM (vonmisses component only)
# plastic strains EPSP_ELNO (six components epsxx, epsyy, ...)
IMPR_RESU(FORMAT='MED',
UNITE=80,
RESU=(_F(RESULTAT=Presul,
NOM_CHAM='DEPL',),
_F(RESULTAT=Presul,
NOM_CHAM='SIEF_NOEU_ELGA',),
_F(RESULTAT=Presul,
NOM_CHAM='EPSI_ELNO_DEPL',),
_F(RESULTAT=Presul,
NOM_CHAM='EPSP_ELNO'),),);

FIN();
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


Now the Syntax I changed to introduce a pressure to the Face "Ftop":


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

LoadPres=AFFE_CHAR_MECA(MODELE=pmode,
PRES_REP=_F(GROUP_MA='Ftop',
PRES=1.98944e8,),);

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

If I try to calculate the problem with a given pressure: the only message from the .erre file is:

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
<EXCEPTION> <COMPOR1_9>

Arret suite à l'échec de l'intégration de la loi de comportement.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Message form the bottom of the .mess file:

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
JDC.py : ERREUR A L'EXECUTION - INTERRUPTION
>> JDC.py : DEBUT RAPPORT
CR d'execution de JDC en MIXTE
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
! <S> Exception utilisateur levee mais pas interceptee. !
! Les bases sont fermees. !
! EchecComportementError : <EXCEPTION LEVEE> COMPOR1_9 !
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
fin CR d'execution de JDC en MIXTE

>> JDC.py : FIN RAPPORT
Fin interpreteur Python
EXECUTION_CODE_ASTER_EXIT_3524=1

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Can anyone help?


Greetings

Basti<br /><br />Post edited by: Basti, at: 2011/09/14 09:59

Hi Kees,

I dont realy expect a concrete value of displacement. I just take the same value of pressure from an other calculation I have done before.
I dont really think about the dimensons of E-Modul and pressure my focus was the syntax, to get calculation able to run.
I will try it out with lower pressure.


greetings

Basti

Hello Basti,

can you take the *.erre and the *.mess file as attachment?

Greeting Markus

I tried it out with lower pressure (the measure of the units was MPa and i normaly work with Pa, so my pressure was 1,9e8 MPa and not 1,9e8 Pa .... ) and it finally works

But I have new questions
the increment of one step is 10 for 4 steps
so we got 40 increments

when I set the pressure to 4.e2 and the &quot;ramp&quot;-function to
0 - 0
t1 - 0.5
t2 - 1.0
t3 - 0.5
t4 - 0

I get additional increments at 20.25 and 20.75. Why?
And the displacement in result of the applying pressure &quot;jumps&quot; in the frame 19 to 20.
I uploaded the Mesh and comm file (the res file is too big), see next post please.

Post edited by: Basti, at: 2011/09/15 12:22<br /><br />Post edited by: Basti, at: 2011/09/15 12:24