#1 2006-12-12 07:17:44

Jm B

Guest

Registered: 2007-11-20

Posts: 0

How to specify the thickness

Hello all,

If I use D_PLAN as the modelisation, how and where do I specify the thickness of the element?

FEMLin=AFFE_MODELE(MAILLAGE=MeshLin,
                   AFFE=_F(TOUT='OUI',
                           PHENOMENE='MECANIQUE',
                           MODELISATION='D_PLAN',),);

Thanks
JMB

laurent

Guest

Registered: 2007-11-20

Posts: 0

Re: How to specify the thickness

Hi

After defining the model, i believe you have to specify which elements to use.
If you use "COQUE" ( or Shell), you will specify the thickness by the EPAIS keyword.
(EPAIS is the short name for EPAISSEUR, which means thickness)

Maybe that would help

modl=AFFE_MODELE(MAILLAGE=mail,
                 AFFE=_F(TOUT='OUI',
                         PHENOMENE='MECANIQUE',
                         MODELISATION='DKT',),);
#Definition of the material

#

as=DEFI_MATERIAU(ELAS=_F(E=210000000000.0,
                         NU=0.3,
                         RHO=7800,),);

chmat=AFFE_MATERIAU(MAILLAGE=mail,
                    AFFE=_F(GROUP_MA='muffler',
                            MATER=as,),);
#Single thickness material

thick=AFFE_CARA_ELEM(MODELE=modl,
                     COQUE=_F(GROUP_MA='muffler',
                              EPAIS=0.0015,),);

Jm B

Guest

Registered: 2007-11-20

Posts: 0

Re: How to specify the thickness

Hello Laurent,

Thank you for your reply.  I will try it.

Regards,
JMB

Jean-Michel PROIX

Guest

Registered: 2007-11-20

Posts: 0

Re: How to specify the thickness

Hello

unfortunately I think that EPAIS is  keyword useful onely for shell elements (COQUE). So it will be inoperant for D_PLAN.

In D_PLAN models, all the results are given without thickness, or (equivalent) with thickness=1. The user has to multiply mis results by the real thickness.

rcbsimoes

Member

Registered: 2010-12-09

Posts: 41

Re: How to specify the thickness

Hi Mr Proix,

could you detail this a little more?

for instance,
a beam was analised as D_Plan, was found to have a 1mm displacement at the edge.

but the beam was not 1 unit thick, but 2.

sort of having two unit thick beams side by side resisting the same charge.

am i suppose to divide the 1mm displacement by the two units?
what about the stresses?
can i assume twice the area so half the stress?

is this correct?
rui simoes