Welcome to the forums. Please post in English or French.

You are not logged in.

## #1 2020-09-15 15:26:48

pironman
Member
Registered: 2018-05-15
Posts: 60

Good morning, I have to calculate the stress on a mold arm, I have two meshes (the arm and the pin) in contact.
I've made two calculation, the first one using LIAISON_MAIL between the two meshes, and no problem.
In the second calculation I use the same .comm file, but I change the LIAISON_MAIL into contact.
Here the two files:

Using LIAISON_MAIL:

``````DEBUT(LANG='EN')

msh_p = LIRE_MAILLAGE(FORMAT='MED',

UNITE=4)

msh_b = LIRE_MAILLAGE(FORMAT='MED',

UNITE=3)

mesh = ASSE_MAILLAGE(MAILLAGE_1=msh_p,

MAILLAGE_2=msh_b,

OPERATION='SUPERPOSE')

model = AFFE_MODELE(AFFE=(_F(MODELISATION=('3D', ),

PHENOMENE='MECANIQUE',

TOUT='OUI'),

_F(GROUP_MA=('E_PERNO_CERNIERA', 'E_STAMPI'),

MODELISATION=('DIS_TR', ),

PHENOMENE='MECANIQUE')),

MAILLAGE=mesh)

elemprop = AFFE_CARA_ELEM(DISCRET=(_F(CARA='K_TR_D_N',

GROUP_MA=('E_PERNO_CERNIERA', ),

VALE=(1000000000000.0, 1000000000000.0, 1000000000000.0, 2.25e+16, 2.25e+16, 0.0)),

_F(CARA='K_TR_D_N',

GROUP_MA=('E_STAMPI', ),

VALE=(0.0, 1000000000000.0, 0.0, 2.25e+16, 0.0, 0.0))),

MODELE=model)

GJS700 = DEFI_MATERIAU(ELAS=_F(E=176000.0,

NU=0.275,

RHO=7.25e-09))

STEEL = DEFI_MATERIAU(ELAS=_F(E=203000.0,

NU=0.3,

RHO=7.9e-09))

fieldmat = AFFE_MATERIAU(AFFE=(_F(GROUP_MA=('BRACCIO', ),

MATER=(GJS700, )),

_F(GROUP_MA=('PERNO', ),

MATER=(STEEL, ))),

MAILLAGE=mesh,

MODELE=model)

FY=-6.53,

GROUP_MA=('FORZA', )),

LIAISON_MAIL=_F(DDL_ESCL='DNOR',

DDL_MAIT='DNOR',

GROUP_MA_ESCL=('CONT_INF', 'CONT_SUPSUP', 'CONT_CENT', 'CONT_SUP'),

GROUP_MA_MAIT=('BRACCIO', ),

TYPE_RACCORD='MASSIF'),

LIAISON_SOLIDE=(_F(GROUP_MA=('E_PERNO_CERNIERA', 'S_PERNO_CERNIERA')),

_F(GROUP_MA=('E_STAMPI', 'S_PERNO_INSERTI'))),

MODELE=model)

reslin = MECA_STATIQUE(CARA_ELEM=elemprop,

CHAM_MATER=fieldmat,

MODELE=model,

SOLVEUR=_F(METHODE='MUMPS'))

reslin = CALC_CHAMP(reuse=reslin,

CRITERES=('SIEQ_ELGA', 'SIEQ_ELNO', 'SIEQ_NOEU'),

RESULTAT=reslin)

IMPR_RESU(FORMAT='MED',

RESU=_F(RESULTAT=reslin),

UNITE=80)

FIN()``````

And using contacts:

``````DEBUT(LANG='EN')

msh_p = LIRE_MAILLAGE(FORMAT='MED',

UNITE=4)

msh_b = LIRE_MAILLAGE(FORMAT='MED',

UNITE=3)

mesh = ASSE_MAILLAGE(MAILLAGE_1=msh_p,

MAILLAGE_2=msh_b,

OPERATION='SUPERPOSE')

model = AFFE_MODELE(AFFE=(_F(MODELISATION=('3D', ),

PHENOMENE='MECANIQUE',

TOUT='OUI'),

_F(GROUP_MA=('E_PERNO_CERNIERA', 'E_STAMPI'),

MODELISATION=('DIS_TR', ),

PHENOMENE='MECANIQUE')),

MAILLAGE=mesh)

elemprop = AFFE_CARA_ELEM(DISCRET=(_F(CARA='K_TR_D_N',

GROUP_MA=('E_PERNO_CERNIERA', ),

VALE=(1000000000000.0, 1000000000000.0, 1000000000000.0, 2.25e+16, 2.25e+16, 0.0)),

_F(CARA='K_TR_D_N',

GROUP_MA=('E_STAMPI', ),

VALE=(0.0, 1000000000000.0, 0.0, 2.25e+16, 0.0, 0.0))),

MODELE=model)

GJS700 = DEFI_MATERIAU(ELAS=_F(E=176000.0,

NU=0.275,

RHO=7.25e-09))

STEEL = DEFI_MATERIAU(ELAS=_F(E=203000.0,

NU=0.3,

RHO=7.9e-09))

fieldmat = AFFE_MATERIAU(AFFE=(_F(GROUP_MA=('BRACCIO', ),

MATER=(GJS700, )),

_F(GROUP_MA=('PERNO', ),

MATER=(STEEL, ))),

MAILLAGE=mesh,

MODELE=model)

linst = DEFI_LIST_REEL(DEBUT=0.0,

INTERVALLE=_F(JUSQU_A=5.0,

PAS=1.0))

FY=-6.53,

GROUP_MA=('FORZA', )),

LIAISON_MAIL=_F(GROUP_MA_ESCL=('CONT_SUPSUP', ),

GROUP_MA_MAIT=('BRACCIO', ),

TYPE_RACCORD='MASSIF'),

LIAISON_SOLIDE=(_F(GROUP_MA=('E_PERNO_CERNIERA', 'S_PERNO_CERNIERA')),

_F(GROUP_MA=('E_STAMPI', 'S_PERNO_INSERTI'))),

MODELE=model)

contact = DEFI_CONTACT(FORMULATION='DISCRETE',

MODELE=model,

ZONE=(_F(ALGO_CONT='CONTRAINTE',

GROUP_MA_ESCL=('CONT_SUP', ),

GROUP_MA_MAIT=('S_PERNO_SUP', )),

_F(ALGO_CONT='CONTRAINTE',

GROUP_MA_ESCL=('CONT_CENT', ),

GROUP_MA_MAIT=('S_PERNO_CENTRO', )),

_F(ALGO_CONT='CONTRAINTE',

GROUP_MA_ESCL=('CONT_INF', ),

GROUP_MA_MAIT=('S_PERNO_INF', ))))

resnonl = STAT_NON_LINE(CARA_ELEM=elemprop,

CHAM_MATER=fieldmat,

COMPORTEMENT=_F(DEFORMATION='PETIT',

GROUP_MA=('BRACCIO', 'PERNO'),

RELATION='ELAS'),

CONTACT=contact,

CONVERGENCE=_F(ITER_GLOB_MAXI=30,

RESI_GLOB_RELA=0.0001),

INCREMENT=_F(LIST_INST=linst),

MODELE=model,

NEWTON=_F(MATRICE='TANGENTE',

PREDICTION='TANGENTE',

REAC_ITER=1),

SOLVEUR=_F(METHODE='MUMPS'))

resnonl = CALC_CHAMP(reuse=resnonl,

CRITERES=('SIEQ_ELGA', 'SIEQ_ELNO', 'SIEQ_NOEU'),

RESULTAT=resnonl)

IMPR_RESU(FORMAT='MED',

RESU=_F(RESULTAT=resnonl),

UNITE=80)

FIN()``````

In the second one, the computation finished successful, but when I try to visualize the results, there are none, all stresses and deflection are zero. I cannot understand why.

Last edited by pironman (2020-09-28 16:02:23)

Offline

## #2 2020-09-18 13:56:30

pironman
Member
Registered: 2018-05-15
Posts: 60

I try to modify the code following the tips found on jeanpierreaubry's book, but the results are the same.
Green light during computation, view the results using paraview, and stress and displacement are all to zero.

``````DEBUT(LANG='EN')

msh_p = LIRE_MAILLAGE(FORMAT='MED',

UNITE=20)

msh_b = LIRE_MAILLAGE(FORMAT='MED',

UNITE=4)

mesh = ASSE_MAILLAGE(MAILLAGE_1=msh_p,

MAILLAGE_2=msh_b,

OPERATION='SUPERPOSE')

mesh = MODI_MAILLAGE(reuse=mesh,

MAILLAGE=mesh,

ORIE_PEAU_3D=(_F(GROUP_MA=('CONT_CENT', )),

_F(GROUP_MA=('CONT_INF', )),

_F(GROUP_MA=('CONT_SUP', )),

_F(GROUP_MA=('CONT_SUPSUP', )),

_F(GROUP_MA=('FORZA', )),

_F(GROUP_MA=('SUP_BRACCIO', )),

_F(GROUP_MA=('S_PERNO_CENTRO', )),

_F(GROUP_MA=('S_PERNO_CERNIERA', )),

_F(GROUP_MA=('S_PERNO_INF', )),

_F(GROUP_MA=('S_PERNO_INSERTI', )),

_F(GROUP_MA=('S_PERNO_SUP', ))))

mesh = DEFI_GROUP(reuse=mesh,

CREA_GROUP_MA=_F(NOM='TOUT',

TOUT='OUI'),

MAILLAGE=mesh)

model = AFFE_MODELE(AFFE=(_F(MODELISATION=('3D', ),

PHENOMENE='MECANIQUE',

TOUT='OUI'),

_F(GROUP_MA=('E_PERNO_CERNIERA', 'E_STAMPI'),

MODELISATION=('DIS_TR', ),

PHENOMENE='MECANIQUE')),

MAILLAGE=mesh)

elemprop = AFFE_CARA_ELEM(DISCRET=(_F(CARA='K_TR_D_N',

GROUP_MA=('E_PERNO_CERNIERA', ),

VALE=(1000000000000.0, 1000000000000.0, 1000000000000.0, 2.25e+16, 2.25e+16, 0.0)),

_F(CARA='K_TR_D_N',

GROUP_MA=('E_STAMPI', ),

VALE=(0.0, 1000000000000.0, 0.0, 2.25e+16, 0.0, 0.0))),

MODELE=model)

GJS700 = DEFI_MATERIAU(ELAS=_F(E=176000.0,

NU=0.275,

RHO=7.25e-09))

STEEL = DEFI_MATERIAU(ELAS=_F(E=203000.0,

NU=0.3,

RHO=7.9e-09))

fieldmat = AFFE_MATERIAU(AFFE=(_F(GROUP_MA=('BRACCIO', ),

MATER=(GJS700, )),

_F(GROUP_MA=('PERNO', ),

MATER=(STEEL, ))),

MAILLAGE=mesh,

MODELE=model)

linst = DEFI_LIST_REEL(DEBUT=0.0,

INTERVALLE=_F(JUSQU_A=5.0,

PAS=1.0))

forza_m = DEFI_FONCTION(NOM_PARA='INST',

PROL_DROITE='CONSTANT',

PROL_GAUCHE='CONSTANT',

VALE=(0.0, 0.0, 5.0, 1.0))

cont = AFFE_CHAR_MECA(LIAISON_MAIL=_F(GROUP_MA_ESCL=('CONT_SUPSUP', ),

GROUP_MA_MAIT=('BRACCIO', ),

TYPE_RACCORD='MASSIF'),

LIAISON_SOLIDE=(_F(GROUP_MA=('E_PERNO_CERNIERA', 'S_PERNO_CERNIERA')),

_F(GROUP_MA=('E_STAMPI', 'S_PERNO_INSERTI'))),

MODELE=model)

contact = DEFI_CONTACT(FORMULATION='DISCRETE',

MODELE=model,

ZONE=(_F(ALGO_CONT='CONTRAINTE',

GROUP_MA_ESCL=('CONT_SUP', ),

GROUP_MA_MAIT=('S_PERNO_SUP', )),

_F(ALGO_CONT='CONTRAINTE',

GROUP_MA_ESCL=('CONT_CENT', ),

GROUP_MA_MAIT=('S_PERNO_CENTRO', )),

_F(ALGO_CONT='CONTRAINTE',

GROUP_MA_ESCL=('CONT_INF', ),

GROUP_MA_MAIT=('S_PERNO_INF', ))))

forza = AFFE_CHAR_MECA(FORCE_FACE=_F(FX=10.4,

FY=-6.53,

GROUP_MA=('FORZA', )),

MODELE=model)

resnonl = STAT_NON_LINE(CARA_ELEM=elemprop,

CHAM_MATER=fieldmat,

COMPORTEMENT=_F(DEFORMATION='PETIT',

GROUP_MA=('BRACCIO', 'PERNO'),

RELATION='ELAS'),

CONTACT=contact,

CONVERGENCE=_F(ITER_GLOB_MAXI=30,

RESI_GLOB_RELA=0.0001),

EXCIT=(_F(CHARGE=cont),

_F(CHARGE=forza,

FONC_MULT=forza_m,

TYPE_CHARGE='FIXE_CSTE')),

INCREMENT=_F(LIST_INST=linst),

MODELE=model,

NEWTON=_F(MATRICE='TANGENTE',

PREDICTION='TANGENTE',

REAC_ITER=1),

SOLVEUR=_F(METHODE='MUMPS'))

IMPR_RESU(FORMAT='MED',

RESU=_F(RESULTAT=resnonl),

UNITE=80)

FIN()``````

Someone can help me?

Thanks

Offline

## #3 2020-09-18 19:41:54

mf
Member
Registered: 2019-06-18
Posts: 118

Hi,

just posting the .comm is not enough to fully understand your problem. That is why nobody answered,

Mario.

Offline

## #4 2020-09-23 09:36:31

pironman
Member
Registered: 2018-05-15
Posts: 60

Sadly, I'm not sure I can give the mesh because of company policies.
I try again repeating all steps, if I cannot in any way solve, I come back.

Offline

## #5 2020-09-24 15:14:28

pironman
Member
Registered: 2018-05-15
Posts: 60

Ok, attached there is the mesh and comm files.
This is a simplified mesh, but the problem is the same: I cannot see any displacement! Like there is no force applied.

Thanks

Attachments:

Offline

## #6 2020-09-24 18:21:56

mf
Member
Registered: 2019-06-18
Posts: 118

Hi,

what seems to be the problem? I just ran your files, and I can see a displacement (see attached image). I mean, I did not check if the results make sense, but, clearly, your calculation works!

Maybe you did not look at t=1 in ParaVis?

Mario.

Attachments:

Offline

## #7 2020-09-25 11:18:22

pironman
Member
Registered: 2018-05-15
Posts: 60

This is a good news.
So, the problem is not the calculation, but my ability to use paraVis.
How can I see that?

Thanks

Offline

## #8 2020-09-25 11:55:45

mf
Member
Registered: 2019-06-18
Posts: 118

Hello,

it's all in the image posted previously.

1) Open your result file in ParaVis ('Open ParaView file' as ParaVis is an adapted version of 'ParaView')
2) Check the Data fields you want to visualize (here all 'ComSup0' are marked) in the Properties tab.
3) press APPLY below
4) jump to timestep t=1 (above in the middle on my screen)
5) Choose the DEPLs to visualize

Then you'll get the image above.

If you want to visualize the deformation additionally (not only the fields projected on the undeformed bodies):

6) Check 'GenerateVectors' and APPLY (it's done in the image but I did not do the following step, obviously I forgot)
7) In Filters ---> Common --> Warp By Vector --> APPLY

Then you'll see the deformed bodies.

Please mark as [SOLVED], thank you.

Mario.

Last edited by mf (2020-09-25 11:57:20)

Attachments:

Offline

## #9 2020-09-25 12:25:57

mf
Member
Registered: 2019-06-18
Posts: 118

..and here is the result with the deformation applied (see 7) above). It is scaled with a factor of 200 for visibility,

Mario.

Attachments:

Offline

## #10 2020-09-28 16:02:53

pironman
Member
Registered: 2018-05-15
Posts: 60