5. Examples

Example 1: Mechanics without thermal expansion

chmat = AFFE_MATERIAU (MAILLAGE = max,

AFFE = (

_F (TOUT = “OUI”, MATER = steel), _F (GROUP_MA =( “gma1”, “gma2”, “gma3”), MATER = alu,),), )

The material called steel is assigned to the entire mesh (except the meshes contained in the groups: gma1, gma2, gma3).

On the cells contained in the groups gma1, gma2, gma3 the material aluminum is affected.

Example 2: Mechanics with thermal expansion

Assignment over the entire mesh of material MAT, some of whose parameters are functions of temperature. In addition, the thermal expansion coefficient is defined for this material. The temporal evolution of the temperature is given via the result EVOTH data structure (evol_ther type). The reference temperature (the one for which the expansion is zero) is equal to 20 degrees.

CHMAT = AFFE_MATERIAU (MAILLAGE = MA,

AFFE =_F (TOUT =” OUI “, MATER = MAT,),

AFFE_VARC =_F (NOM_VARC =” TEMP “, EVOL =”, = EVOTH, VALE_REF =20.),

)

Example 3: Mechanics with thermal expansion + complex modelling

In the previous example, the thermal evolution (EVOTH) applies to all elements of the model. But it may happen that this situation is unrealistic for certain complex models. It is then necessary to repeat the keyword AFFE_VARC/NOM_VARC =” TEMP “several times to affect different thermal evolutions on different parts of the model.

In the following example, the model is a 3D model in which steel reinforcements are immersed. A thermal calculation was carried out beforehand without taking into account the reinforcements. We got a result that we called EVOTH3D. The temperature of the nodes of the reinforcement elements is then unknown. If, moreover, it is possible to evaluate the temperature of the frames (measurements,…) and this temperature is stored in the field (TEMP_ARM), it is then possible to perform the mechanical calculation of thermal expansion with the following material field:

CHMAT = AFFE_MATERIAU (MAILLAGE = MA,

AFFE =_F (…),

AFFE_VARC =(

_F (NOM_VARC =” TEMP “, GROUP_MA =” VOLUM”, EVOL = EVOTH3D, VALE_REF =20.),

_F (NOM_VARC =” TEMP “, GROUP_MA =” ARMA”, CHAM_GD = TEMP_ARM, VALE_REF =20.),

))

Example 4: Mechanics with influence of irradiation

Assignment over the entire mesh of material MAT, some of whose parameters are functions of irradiation. The temporal evolution of irradiation is given via the SD result EVOL = FLUENC.

CHMAT = AFFE_MATERIAU (MAILLAGE = MA,

AFFE =_F (TOUT =” OUI “, MATER = MAT,),

AFFE_VARC =_F (NOM_VARC =” IRRA “, EVOL = FLUENC,),

)

Example 5: Mechanical calculation with an imposed Young’s modulus field

In this example (from the ssnv130c test case), we want to illustrate the possibility of using a Young’s modulus field that is assumed to be known (CHYOUNG). For example, this field is read from a file (LIRE_CHAMP) or it is the result of a calculation.

The « trick » consists in defining a material for which the Young’s modulus (keyword ELAS /E) is the « identity » function of the variable “NEUT1” and the field CHYOUNG is assigned as the command variable “NEUT1”.

CHYOUNG =…

NU_F = DEFI_CONSTANTE (VALE =0.3)

E_F = DEFI_FONCTION (NOM_PARA =” NEUT1 “, VALE =( -1.E-9, -1.E-9, 1.E+9,1.E+9))

MY= DEFI_MATERIAU (ELAS_FO =_F (E=E_F, NU= NU_F,),);

CM= AFFE_MATERIAU (MAILLAGE =M,

AFFE =_F (TOUT = “OUI”, MATER = MA),

AFFE_VARC =_F (NOM_VARC =” NEUT1 “, CHAM_GD = CHYOUNG),

)