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

You are not logged in.

#1 2020-06-26 15:54:49

marcoC
Member
Registered: 2018-06-13
Posts: 39

extract external resultant moments

I have a shell structure loaded with a momentum on some nodes. Is there the possibility to extract the external moment resultant to check if the loading is correct ? In other words, there is the analogous for external moments as for reaction forces REAC_NODA ?

Regards,

Marco

Offline

#2 2020-06-26 20:29:39

tpa
Member
From: Denmark
Registered: 2009-04-14
Posts: 39

Re: extract external resultant moments

Yes, something like:

Calculate the fields:
reslin = CALC_CHAMP(
  FORCE=('FORC_NODA'),
  RESULTAT=reslin,
  TOUT='OUI')

Extract the group of nodes to a table:
table = POST_RELEVE_T(
  ACTION=(_F(
      GROUP_NO=('P2', 'P1'),
      INTITULE='1',
      NOM_CHAM='FORC_NODA',
      OPERATION=('EXTRACTION', ),
      RESULTAT=reslin,
      TOUT_CMP='OUI'
    ))
)

And dump the table to a text file on UNIT 8:
IMPR_TABLE(
  FORMAT='TABLEAU',
  TABLE=table,
  UNITE=8
)

- will give a table like the attached file. This was for a small beam model with a force FZ=-1000 on N2 and N1 fully constrained. This load is clear from the table as well as the reaction forces at N1.


Attachments:
Study1.table.txt, Size: 874 B, Downloads: 18

Offline

#3 2020-06-28 10:45:01

marcoC
Member
Registered: 2018-06-13
Posts: 39

Re: extract external resultant moments

Thank you very much.
I will try.
Regards,
Marco

Offline

#4 2020-06-29 16:42:40

marcoC
Member
Registered: 2018-06-13
Posts: 39

Re: extract external resultant moments

My problem is to verify that an external moment applied to a group of nodes is effectively applied.
If I have force loads it is simple to extract REAC_NODA and check if the sum of the external force applied equals REAC_NODA throught RESULTANTE operator.
But, if the load is a moment applied to a group of nodes, how can I perform the same check as for external force loads ?
Regards,
Marco

Offline

#5 2020-06-30 07:46:29

sameer21101970
Member
Registered: 2019-09-06
Posts: 163

Re: extract external resultant moments

i too am working on same.

if  MZ is define by Nodale Force on Single Node (0D element ) Liasion Solid to some nodes. Then MZ is divided by number of nodes it is connecting. Understand my understanding is right.
How  to Extract Data in Graphical Form VMIS vs time, VMIS vs Displacemnt, MZ vs time, MZ vs Displacemnt.

Offline

#6 2020-07-05 12:25:08

Johannes_ACKVA
Member
From: Ingenieurbüro für Mechanik, DE
Registered: 2009-11-04
Posts: 690
Website

Re: extract external resultant moments

hello

Result=CALC_CHAMP(reuse =Result,
                  RESULTAT=Result,
                  FORCE=('FORC_NODA','REAC_NODA',),)

# sum of applied forces and moments at loaded nodes
SumAppl=POST_RELEVE_T(ACTION=_F(OPERATION='EXTRACTION',
                                 INTITULE='SumApplForce',
                                 RESULTAT=Result,
                                 NOM_CHAM='FORC_NODA',
                                 GROUP_NO='LOADED_ELEMENTS',
                                 RESULTANTE=('DX','DY','DZ',),
                                 MOMENT=('DRX','DRY','DRZ',),
                                 POINT=(0,0,0,),),)

# sum of reaction forces and moments at clamped nodes
SumReac=POST_RELEVE_T(ACTION=_F(OPERATION='EXTRACTION',
                                 INTITULE='SumReacForce',
                                 RESULTAT=Result,
                                 NOM_CHAM='REAC_NODA',
                                 GROUP_NO='Clamped_Nodes',
                                 RESULTANTE=('DX','DY','DZ',),
                                 MOMENT=('DRX','DRY','DRZ',),
                                 POINT=(0,0,0,),),)

Of couse, the sumed moment depends on the coodinates of POINT

Also consider:
** REAC_NODA is the field of reaction forces/moments
** FORC_NODA is the field of the sum of reaction + applies forces and moments

The latter means that "SumAppl" is the sum of applied forces and moments only if there is no reaction at those nodes

Regards
Johannes_ACKVA

______________________________________________________________________
CODE-ASTER-courses at Ingenieurbüro für Mechanik, Germany

ONLINE-COURSES STARTING AT AUGUST 2020


Ingenieurbüro für Mechanik
D 91717 Wassertrüdingen / Germany

www.code-aster.de                                                Training & Support for NASTRAN and CODE-ASTER

Offline

#7 2020-07-07 07:45:53

sameer21101970
Member
Registered: 2019-09-06
Posts: 163

Re: extract external resultant moments

Many Thanks Johannes,

your experience is helping entire code-aster community.

Offline

#8 2020-07-07 11:41:38

sameer21101970
Member
Registered: 2019-09-06
Posts: 163

Re: extract external resultant moments

After studying the Data Table by above procedure, even extracting table in paraview gave same results.

Confusion is I Want to apply Torque to Gear. Force x PCD/2.
I have Liasion Solid 0D node/element to PCD of Gear Nodes.

As per CodeAster,
If i define MY = 100 in codeaster
given PCD of gear is = 40

and Distance of Centre of Gear to Global axis (0,0,0) is 60.

Then Force_Noda has below reading Moment _Y = 100 x 60 = 6000.

How can I EXTRACT Exact Torque Applied on PCD from 0D Element.? ? something i am missing.

##ASTER 14.04.00 CONCEPT table CALCULE LE 07/07/2020 A 13:49:56 DE TYPE           
#TABLE_SDASTER                                                                   
INTITULE         RESU     NOM_CHAM         NUME_ORDRE   INST         RESULT_X     RESULT_Y     RESULT_Z     MOMENT_X     MOMENT_Y     MOMENT_Z   
SumAppliForce    resnonl  FORC_NODA                   0  0.00000E+00  0.00000E+00  0.00000E+00  0.00000E+00  0.00000E+00  0.00000E+00  0.00000E+00
SumAppliForce    resnonl  FORC_NODA                   1  1.00000E-02 -1.00000E+02  0.00000E+00  1.00000E+02 -5.24509E-04  6.00000E+03 -2.76717E-05
SumAppliForce    resnonl  FORC_NODA                   2  2.00000E-02 -1.00000E+02  0.00000E+00  1.00000E+02 -4.77644E-04  6.00000E+03 -8.57756E-05
SumAppliForce    resnonl  FORC_NODA                   3  3.00000E-02 -1.00000E+02  0.00000E+00  1.00000E+02 -4.67713E-04  6.00000E+03 -9.62894E-05
SumAppliForce    resnonl  FORC_NODA                   4  4.00000E-02 -1.00000E+02  0.00000E+00  1.00000E+02 -4.74831E-04  6.00000E+03 -6.85460E-05
SumAppliForce    resnonl  FORC_NODA                   5  5.00000E-02 -1.00000E+02  0.00000E+00  1.00000E+02 -4.88431E-04  6.00000E+03 -2.12760E-04
SumAppliForce    resnonl  FORC_NODA                   6  6.00000E-02 -1.00000E+02  0.00000E+00  1.00000E+02 -5.23289E-04  6.00000E+03 -5.00975E-05
SumAppliForce    resnonl  FORC_NODA                   7  7.00000E-02 -1.00000E+02  0.00000E+00  1.00000E+02 -4.35458E-04  6.00000E+03 -7.24016E-05
SumAppliForce    resnonl  FORC_NODA                   8  8.00000E-02 -1.00000E+02  0.00000E+00  1.00000E+02 -4.97776E-04  6.00000E+03 -1.16238E-04
SumAppliForce    resnonl  FORC_NODA                   9  9.00000E-02 -1.00000E+02  0.00000E+00  1.00000E+02 -4.62523E-04  6.00000E+03 -1.00547E-04
SumAppliForce    resnonl  FORC_NODA                  10  1.00000E-01 -1.00000E+02  0.00000E+00  1.00000E+02 -4.97029E-04  6.00000E+03 -1.27396E-04
SumAppliForce    resnonl  FORC_NODA                  11  1.10000E-01 -1.00000E+02  0.00000E+00  1.00000E+02 -4.85335E-04  6.00001E+03 -9.94227E-05
SumAppliForce    resnonl  FORC_NODA                  12  1.20000E-01 -1.00000E+02  0.00000E+00  1.00000E+02 -4.72076E-04  6.00001E+03 -1.25889E-04
SumAppliForce    resnonl  FORC_NODA                  13  1.30000E-01 -1.00000E+02  0.00000E+00  1.00000E+02 -4.87603E-04  6.00001E+03 -1.03059E-04
SumAppliForce    resnonl  FORC_NODA                  14  1.40000E-01 -1.00000E+02  0.00000E+00  1.00000E+02 -4.70048E-04  6.00001E+03 -1.47030E-04
SumAppliForce    resnonl  FORC_NODA                  15  1.50000E-01 -1.00000E+02  0.00000E+00  1.00000E+02 -4.92420E-04  6.00001E+03 -1.23930E-04
SumAppliForce    resnonl  FORC_NODA                  16  1.60000E-01 -1.00000E+02  0.00000E+00  1.00000E+02 -3.95328E-04  6.00001E+03 -2.87520E-04
SumAppliForce    resnonl  FORC_NODA                  17  1.70000E-01 -1.00000E+02  0.00000E+00  1.00000E+02 -4.12239E-04  6.00001E+03 -1.61431E-04
SumAppliForce    resnonl  FORC_NODA                  18  1.80000E-01 -1.00000E+02  0.00000E+00  1.00000E+02 -3.86970E-04  6.00001E+03 -1.38231E-04

Last edited by sameer21101970 (2020-07-07 11:43:58)

Offline