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

You are not logged in.

#1 2020-08-13 07:38:00

marco.mueller
Member
Registered: 2020-01-16
Posts: 24

Usage of DYNA_NON_LINE for EN 62262 test

Bonjour,

I'd like to use the dynamic solver to simulate the EN 62262 test, to get basic knowledge about the (plastic) deformation of our parts:

Is there a general objection regarding this? (I'm aware of the fact that implicit methods are not very well suited regarding calculation efficiency)

In my test model I face the issue that the initial velocity moves the impact body into the wrong direction and with a velocity differing from the one I applied. It's quite silly, but I can't find the reason why. Can somebody help me out?

A final question: Can I model the thin body with 2D elements (COQUE3D preferred) in this constellation? I tried to, but found that the boundary conditions were not properly applied.

Thanks
Marco


Here my comm-file, the whole Salome Meca case is attached:

Netz1 = LIRE_MAILLAGE(FORMAT='MED',
                      UNITE=20)

Netz2 = LIRE_MAILLAGE(FORMAT='MED',
                      UNITE=2)

NetzL = ASSE_MAILLAGE(MAILLAGE_1=Netz1,
                      MAILLAGE_2=Netz2,
                      OPERATION='SUPERPOSE')

NetzQ = CREA_MAILLAGE(LINE_QUAD=_F(TOUT='OUI'),
                      MAILLAGE=NetzL)

FEModell = AFFE_MODELE(AFFE=_F(MODELISATION=('3D', ),
                               PHENOMENE='MECANIQUE',
                               TOUT='OUI'),
                       MAILLAGE=NetzQ)

Kugelmat = DEFI_MATERIAU(ELAS=_F(E=210000.0,
                                 NU=0.316,
                                 RHO=1.91e-08))

Matdef = AFFE_MATERIAU(AFFE=_F(MATER=(Kugelmat, ),
                               TOUT='OUI'),
                       MODELE=FEModell)

Zeiten = DEFI_LIST_REEL(DEBUT=0.0,
                        INTERVALLE=_F(JUSQU_A=0.04,
                                      NOMBRE=20))

ZeitenI = DEFI_LIST_INST(DEFI_LIST=_F(LIST_INST=Zeiten),
                         METHODE='AUTO')

RB = AFFE_CHAR_MECA(DDL_IMPO=(_F(DX=0.0,
                                 DY=0.0,
                                 DZ=0.0,
                                 GROUP_NO=('Objekt_Fix', )),
                              _F(DX=0.0,
                                 GROUP_NO=('Objekt_SymX', 'Kugel_SymX')),
                              _F(DY=0.0,
                                 GROUP_NO=('Objekt_SymY', 'Kugel_SymY'))),
                    MODELE=FEModell)

Kontakt = DEFI_CONTACT(FORMULATION='DISCRETE',
                       MODELE=FEModell,
                       ZONE=_F(ALGO_CONT='PENALISATION',
                               E_N=2100.0,
                               GROUP_MA_ESCL=('Kugel_Kontakt', ),
                               GROUP_MA_MAIT=('Objekt_Kontakt', )))

IniVel = CREA_CHAMP(AFFE=_F(GROUP_NO=('Kugel', ),
                            NOM_CMP=('DX', 'DY', 'DZ'),
                            VALE=(0.0, 0.0, 2801.0)),
                    MODELE=FEModell,
                    OPERATION='AFFE',
                    TYPE_CHAM='NOEU_DEPL_R')

NLinDyn = DYNA_NON_LINE(CHAM_MATER=Matdef,
                        CONTACT=Kontakt,
                        ETAT_INIT=_F(VITE=IniVel),
                        EXCIT=_F(CHARGE=RB),
                        INCREMENT=_F(LIST_INST=ZeitenI),
                        MODELE=FEModell,
                        SCHEMA_TEMPS=_F(FORMULATION='DEPLACEMENT',
                                        SCHEMA='HHT'))

Proj = PROJ_CHAMP(MAILLAGE_2=NetzL,
                  MODELE_1=FEModell,
                  RESULTAT=NLinDyn)

Sig1 = CALC_CHAMP(CONTRAINTE=('SIGM_ELNO', ),
                  FORCE=('REAC_NODA', ),
                  RESULTAT=NLinDyn)

Sig3 = CALC_CHAMP(CONTRAINTE=('SIGM_NOEU', ),
                  CRITERES=('SIEQ_ELNO', 'SIEQ_NOEU'),
                  RESULTAT=NLinDyn)

Reak = POST_RELEVE_T(ACTION=_F(GROUP_NO=('Objekt_Fix', ),
                               INTITULE='Reaktionskraft',
                               NOM_CHAM='REAC_NODA',
                               OPERATION=('EXTRACTION', ),
                               RESULTANTE=('DX', 'DY', 'DZ'),
                               RESULTAT=Sig1))

IMPR_RESU(FORMAT='MED',
          RESU=(_F(NOM_CHAM=('DEPL', ),
                   NOM_CHAM_MED=('Verschiebungen', ),
                   RESULTAT=Proj),
                _F(NOM_CHAM=('SIEQ_ELNO', ),
                   NOM_CHAM_MED=('Spannungen', ),
                   RESULTAT=Sig3)),
          UNITE=80)

IMPR_TABLE(TABLE=Reak,
           UNITE=8)


Attachments:
fem.zip, Size: 134.15 KiB, Downloads: 29

Offline

#2 2020-08-13 16:09:18

sameer21101970
Member
Registered: 2019-09-06
Posts: 246

Re: Usage of DYNA_NON_LINE for EN 62262 test

Kugelmat = DEFI_MATERIAU(ELAS=_F(E=210000.0,
                                 NU=0.316,
                                 RHO=1.91e-08))

i have not seen your zip file, but you need to provide more details on material behaviour. for e.g strain vs strain data table for your kind of plastic

Last edited by sameer21101970 (2020-08-13 16:09:55)

Offline

#3 2020-08-14 09:09:13

marco.mueller
Member
Registered: 2020-01-16
Posts: 24

Re: Usage of DYNA_NON_LINE for EN 62262 test

I first wanted to make sure to get the dynamics running, so I did not care about the material so far - instead of choosing a density that leads to an impact body mass of 5 kg, according to the test.

In the end it would be sufficient to have a bilinear material for the test object with a simple stiffening model.

Last edited by marco.mueller (2020-08-14 09:10:33)

Offline

#4 2020-08-24 08:48:29

marco.mueller
Member
Registered: 2020-01-16
Posts: 24

Re: Usage of DYNA_NON_LINE for EN 62262 test

I've found the issue: It was related to the CREA_MAILLAGE(LINE_QUAD) operation. Now, I provide a quadratic mesh and the dynamics work, also the whole case runs fine (with 3D meshing).

Coming back to my initial post: Is there a way to use 2D elements in conjunction with DYNA_NON_LINE and great deformations? I've found that COQUE_3D is not supported for that. I've also read in some thread 2 months ago, that a new (universal?) 2D element formulation is on the way ... Can anyone provide more details about that?

Thanks
Marco

Offline