on 26-Aug-2018 (Sun)

Meshes in other formats Commands PRE_*** to convert to Aster format: PRE_GIBI, PRE_IDEAS, PRE_GMSH Example: PRE_***() mymesh = LIRE_MAILLAGE(FORMAT=‘ASTER’)

Axi-symmetrical model AXIS: Node coordinates: y must be the axis of symmetry and the values of x must be positive

14 - Code_Aster and Salome-Meca course material GNU FDL Licence Other points to pay attention to: Axi-symmetrical model AXIS: Node coordinates: y must be the axis of symmetry and the values of x must be positive Orientation of the normals: Command MODI_MAILLAGE [U4.23.04] Checks the orientation of the normal vector for plate/shell elements as well as for the borders where a pressure is applied (2D/3D) Reorients properly the cells where contact is defined ◊ ORIE_NORM_COQUE = _F( This keyword is for testing whether in a list of surface mesh cells (shells), the normals are mutually consistent. Otherwise, some cells are redirected. ◊ ORIE_PEAU_2D = ◊ ORIE_PEAU_3D = These keywords are used to redirect the mesh edges so that their normals are consistent (pointing towards the outside of the material). This is a prerequisite if, for example, one wants to apply a pressure load on this "skin".

steel=DEFI_MATERIAU( ELAS =_F(E=2.1.E11, NU=0.3,),) TRACTION =_F( SIGM = CTRACB),) mater=AFFE_MATERIAU(MAILLAGE=mesh, AFFE=_F(TOUT='OUI', MATER=steel,),) result=STAT_NON_LINE( ... CHAM_MATER=mater, COMPORTEMENT=_F( RELATION = 'VMIS_ISOT_TRAC'),)

One must input the description of the problem prior to solving The model: MODELE Materials: CHAM_MATER Geometrical characteristics (for structural elements): CARA_ELEM Loadings: EXCIT A time stepping if necessary: LIST_INST

Direct solvers MULT_FRONT (multi-frontal): Default method. Universal solver, very robust. Not recommended for mixed models of X-FEM, incompressible ... MUMPS (MUltifrontal Massively Parallel sparse direct Solver): external solver. Slightly broader scope than MULT_FRONT. Provides access to parallelism.

Iterative solvers GCPC (Preconditioned conjugate gradient): recommended method for thermics. Useful for well conditioned, large problems. PETSC: external multi-method solver. Very fast and robust when associated with pre- conditioner LDLT_SP. Provides access to parallelism.

Parametric resolution Building submitted to an earthquake 300 calculations of 2h each total execution time in 6h on 100 procs Speed-up = 100 Solve the same problem by varying a set of parameters (Young's modulus, thickness, etc. ...) Automatic run of distributed calculations only with ASTK GUI Nominal command file + ranges of variation of a parameter (or more) Integer, real, text [U2.08.07] “Distribution of parametric calculations

Location of the values: Fields on nodes (NOEU) ; On the elements: Fields by element on Gauss points (ELGA); Fields by element on nodes (ELNO); Constant field on element (ELEM). Naming rule XXXX_YYYY : Four first characters: name of the quantity (SIGM, EPSI, ERRE, etc); Four last characters : location (NOEU, ELGA, ELNO or ELEM). Examples: Exception! DEPL, VITE, ACCE SIEQ_ELNO, SIGM_ELNO

Resolution operators produce typed data structures: resultat The type depends on the operator EVOL_ELAS (linear mechanics), EVOL_NOLI (non-linear mechanics), EVOL_THER (linear thermics), MODE_MECA (modal analysis), ...

Calculating physical fields or performing mathematical operations: CALC_CHAMP / POST_ELEM Produces fields and tables.

CALC_CHAMP operator [U4.81.04]: Creates or completes a result data structure; Calculation of stresses, strains, energies, criteria, error indicators,… POST_ELEM operator [U4.81.22]: Creates a table. Calculation of energies (potential, elastic, kinetic, dissipated,…) ; Calculation of integrals or average quantities

Handling fields, tables and data structures: CREA_CHAMP / CREA_RESU / CREA_TABLE / CALC_TABLE Produces fields, results and tables. CREA_CHAMP operator [U4.72.04]: Creates single fields (cham_gd), CREA_RESU operator [U4.44.12] : Creates a result data structure from input fields. CREA_TABLE operator [U4.33.02]: Creates a table from a function or a list of scalars. CALC_TABLE operator [U4.33.03]: Manipulates data from tables like a spreadsheet.

Extracting values : MACR_LIGN_COUPE: Extract component values from fields on: Nodes; Group of nodes; Cut lines; Example: components DX, DY, DZ from DEPL on node N125. POST_RELEVE_T: Performs: Averaging; Resultants and moments of vector fields; Invariants of tensor fields; Directional trace fields.

Outputing results: IMPR_RESU / FORMAT=‘RESULTAT’ This procedure allows you to write either: Fields on nodes (displacement, temperature, eigen modes, static modes, …); Fields by elements on nodes; Fields by elements on Gauss points (stress, generalized efforts, internal variables,…). Parameters form a result data structure; Min and max values; Restriction between two bounds; Etc

Extract the evolution of a quantity as a function of another ([U4.32.04]); From a result data structure, the generated function corresponds to the temporal evolution of a component of a node or Gauss point of the model. From a table data structure, this operator can extract the evolution of two parameters. % COURBE SIGMA YY AU POINT G EN FONCTION DU TEMPS SYYG = RECU_FONCTION ( RESULTAT = RESUNL, NOM_CMP = 'SIYY', NOM_CHAM = 'SIEF_NOEU', GROUP_NO = G, TOUT_ORDRE = 'OUI') ; % COURBE SIGMA XX A T DONNE EN FONCTION DE L’ABSCISSE fct = RECU_FONCTION ( TABLE = tab, PARA_X = ‘ABSC_CURV’, PARA_Y = 'SIXX') ;

FONCTION : tabulated (discrete) function depending on one parameter NAPPE : tabulated (discrete) function depending on two parameters FORMULE : continuum mathematic formula depending on several

ABSC_CURV Curvilinear abscissa EPSI Strain DX DY DZ Displacement along X Displacement along Y Displacement along Z SIGM Stress DRX DRY DRZ Rotation around X Rotation around Y Rotation around Z INST Time X Y Z Coordinate X Coordinate Y Coordinate Z TEMP Temperature

Complex function : VALE_C instead of VALE

ABSC=DEFI_LIST_REEL(VALE=(1.,2.,3.,4.,)) ORDO=DEFI_LIST_REEL(VALE=(2.,3.,4.,3.,)) fonc=DEFI_FONCTION( NOM_PARA='INST', VALE_PARA=ABSC, VALE_FONC=ORDO, PROL_GAUCHE='EXCLU', PROL_DROITE='CONSTANT')

Using FONCTION or FORMULE ? • Function are tabulated : faster when using in low-level Fortran (behavior law for instance) • Formulas are « exact » : more precise • Defining FORMULE and use CALC_FONC_INTERP

Where using functions ? • Boundary conditions (AFFE_CHAR_MECA_F command for instance) • Behavior law : traction curve for elastoplastic, laws depending on temperature • Multiplicative functions for boundary conditions in non- linear

Read function from file LIRE_FONCTION Get information about function (maximum, rms, etc.) INFO_FONCTION Print a function (for XmGrace software for instance) IMPR_FUNCTION Create function from results or from field RECU_FONCTION

stable: this is the production version used by EDF for its industrial studies. It is released every six months.

testing: this is a snapshot of the development version. It is released every six months.

unstable: this is the version that integrates improvements. It is updated daily.