GROUP_NO in Aster

johan

I used to apply loads to the end of a pipe or pressure vessel nozzle using the commands below. (With credit to the torque example in CAELINUX.)

C_node is a node on the pipe centerline to which the loads are applied. Node group Load_MPC is on the edge of the pipe and includes C_node.

How would one do the same thing now that, as I understand the error messages I get, GROUP_NO is not available any more?

Thanks in advance.

.....

MODE=AFFE_MODELE(MAILLAGE=MAIL,

AFFE=(_F(TOUT='OUI',

PHENOMENE='MECANIQUE',

MODELISATION='3D',),

_F(GROUP_NO='C_node',

PHENOMENE='MECANIQUE',

MODELISATION='DIS_TR',),),);

CARA=AFFE_CARA_ELEM(MODELE=MODE,

DISCRET=_F(CARA='K_TR_D_N',

GROUP_NO='C_node',

VALE=(0.0,0.0,0.0,0.0,0.0,0.0,),),);

........

BC=AFFE_CHAR_MECA(MODELE=MODE,

DDL_IMPO=(_F(GROUP_MA='X_Fix_F',

DX=0.0,),

_F(GROUP_MA='Y_Fix_E',

DY=0.0,),

_F(GROUP_MA='Z_Fix_E',

DZ=0.0,),),

LIAISON_SOLIDE=_F(GROUP_NO='Load_MPC',),

FORCE_NODALE=_F(GROUP_NO='C_node',

FX=FNX,

etc

jeanpierreaubry

hello

some more information is required

maybe the files of the problem

as far as i am concerned in my daily work GROUP_NO is still available as of today

jean pierre aubry

johan

jeanpierreaubry

Thanks for this very prompt reply. Appreciated.

I do not believe that there is something wrong with the command file, because it ran without any problems, using Salome-Meca 2016, except that I got an error message which I have chosen to ignore.

I am now trying to run the same commands in AsterStudy. My mesh file has the node groups defined. In AsterStudy there are no node groups to choose from.

Screen shots of the above are attached.

If I import the old .comm file into AsterStudy I get an error message which says something like "incompatable groups", which I think points to the same problem.

Attached file:
Screenshots.pdf, 89044kb

jeanpierreaubry

obviously i read your first post too fast

you create an element DIS_TR

this has to be done on an element, not a node

hence the use of GROUP_MA instead of GROUP_NO

(looks like it was allowed previously, i do not remember)

you may have to create a point element POI1 onto the node

in the .comm file if not done in the mesher here Salome

i use Gmsh as a mesher which automatically creates a point element on every node

this is explained in my book

johan

Thanks

I have never worked with point elements, but I will give it a go.

Thanks again

johan

It worked like a charm. Thanks for the help.