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#1 2019-03-22 13:20:28

PietroC
Member
Registered: 2019-03-22
Posts: 5

[solved] Nodal forces function of nodal cordinates

Hi everybody,
this is my first simulation in Code Aster; I'll use this software for my final thesis (fluid structure interaction of hydrofoil).
My supervisor asked me to test the various elements that Code Aster provides to see what will be the best for our kind of study; he wants to compare the results obtained (z displacement of the central node x=L/2; y=L/2) using different kind of elements (2d elements) with a test case he has studied already with others commerical and in-house university softwares.
The test case I'm studying is:
square plate L/h=10,  isotropic material E=70000, v=0.3, L=100 mm
dx=0, dy=0, dz=0 on all the edges; rotations are not blocked
load: nodal forces Fz as a function of nodes coordinates : 0.625*sin(pi*X/L)*sin(pi*Y/L) 
mesh: quadrilater 120 step per edge
I'm having trouble defining the load as a function of coordinates; I've read all the documentation about that and some threads on the forum but I still get errors. I don't know what I'm doing wrong (also cause the ZZZZ100 – Functions, tablecloths, formulas testcase is not available anymore). I've tried the simulation with constant Fz and everything is fine (so the problem is indeed in the definition of the function).
I add the command file and the message error; hope that I was clear and that this topic can help other users.
Greetings

Pietro

message error:
# ------------------------------------------------------------------------------------------
ERREUR DE COMPILATION DANS ACCAS - INTERRUPTION
>> JDC.py : DEBUT RAPPORT
CR phase d'initialisation
   !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
   ! Compilation impossible :   File "fort.1", line 27 !
   !      NAP= FORMULA (NOM_PARA = (‘X’, ‘Y’), !
   !                                ^                  !
   !  SyntaxError: invalid syntax                      !
   !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
fin CR phase d'initialisation

>> JDC.py : FIN RAPPORT
EXECUTION_CODE_ASTER_EXIT_11088-pitah-VirtualBox=1

<I>_EXIT_CODE = 1

Last edited by PietroC (2019-03-24 16:22:04)


Attachments:
Stage_3.comm, Size: 2.02 KiB, Downloads: 65

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#2 2019-03-22 14:43:19

chenghui62000
Member
From: Norway
Registered: 2018-06-19
Posts: 63

Re: [solved] Nodal forces function of nodal cordinates

hi,
there is a mistake in the syntax:
you should use "NAP= FORMULE(....)"
instead of          "NAP= FORMULA(...) "

best regards,
Hui Cheng

Last edited by chenghui62000 (2019-03-22 14:43:41)

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#3 2019-03-22 16:59:01

PietroC
Member
Registered: 2019-03-22
Posts: 5

Re: [solved] Nodal forces function of nodal cordinates

thank you for your reply. I wrote FORMULA because in the documentation I found FORMULA instead of FORMULE everywhere (but i noticed that other users use FORMULE in their command file).
I changed that sintax, but i still get another sintax error with a different exit code (2993).

would you be so kind to check this part of the command file and tell me if i made some mistake?
Thanks in advice
Pietro

NAP= FORMULE (NOM_PARA = (‘X’, ‘Y’),
VALE = ‘0.625*(sin(X)*sin(Y)) ‘)

listrX = DEFI_LIST_REEL(DEBUT=0.0,
                       INTERVALLE=_F(JUSQU_A=100.0,
                                     NOMBRE=120))
listrY = DEFI_LIST_REEL(DEBUT=0.0,
                       INTERVALLE=_F(JUSQU_A=100.0,
                                     NOMBRE=120))

SI1 = CALC_FONC_INTERP ( FORMULE=NAP,
NOM_RESU = ‘DEPL’,
NOM_PARA='X', 'Y',
LIST_PARA = listrX, listrY
PROL_GAUCHE_FONC=' EXCLU',
PROL_DROITE_FONC=' CONSTANT',
INTERPOL_FONC=' LIN',
TITRE=' FUNCTION SINUS',)



load0 = AFFE_CHAR_MECA(DDL_IMPO=_F(DX=0.0,
                                   DY=0.0,
                                   DZ=0.0,
                                   GROUP_MA=('BC', )),
                       MODELE=model)

load = AFFE_CHAR_MECA_F(FORCE_NODALE=_F(FZ='DEPL',
                                      GROUP_NO=('Group_1', )),
                      MODELE=model)

Last edited by PietroC (2019-03-23 10:05:25)

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#4 2019-03-23 09:57:58

chenghui62000
Member
From: Norway
Registered: 2018-06-19
Posts: 63

Re: [solved] Nodal forces function of nodal cordinates

sorry I am also a new user. I did not find any syntax in your command file. maybe you can post the error message. that might be more helpful.

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#5 2019-03-24 16:20:37

PietroC
Member
Registered: 2019-03-22
Posts: 5

Re: [solved] Nodal forces function of nodal cordinates

after a while I figured out how to solve my problem and i got exactly what I was looking for. In the attachements the new command file ( working one).
In the next days i'll post some updates on the result for the different kind of elements and the comparison with other softwares (if someone is interested in it).


Attachments:
Stage_1.comm, Size: 2.53 KiB, Downloads: 51

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