nonlinear buckling with restart
nonlinear buckling with restart
(OP)
hi to everybody... i've some problem with a simple test of a cantilevered beam subject to a compression...
the body is made by a solid cylinder.
i've preformed nonlinear static analysis at first
then restarted from loadstep 5
i get the following error
*** USER FATAL MESSAGE 4512 (CASE02)
SUBCASE 2 REFERENCES UNDEFINED NLPARM CARD WITH ID =2.
*** SYSTEM FATAL MESSAGE 3007 (CASE)
ILLEGAL INPUT TO SUBROUTINE CASE02
here attached both bdf (buckle is the nonlinear, buckle2 is the restarted)
the body is made by a solid cylinder.
i've preformed nonlinear static analysis at first
then restarted from loadstep 5
i get the following error
*** USER FATAL MESSAGE 4512 (CASE02)
SUBCASE 2 REFERENCES UNDEFINED NLPARM CARD WITH ID =2.
*** SYSTEM FATAL MESSAGE 3007 (CASE)
ILLEGAL INPUT TO SUBROUTINE CASE02
here attached both bdf (buckle is the nonlinear, buckle2 is the restarted)





RE: nonlinear buckling with restart
You can go to page 201 in the Nastran v2001 release guide for an example of nonlinear buckling analysis in a single job. Search nlsolidb in your Nastran installation folder, and you will find the example file.
RE: nonlinear buckling with restart
I've learned a lot!!
I've still some problems... i've performed another simply test with a cantilevered plate (solid)
used PARAM,BUCKLE,2 ( i've found an integrated option in subcase parameter)
made a comparision between nlsolidb and mine and main differeces are in METHOD and EIGRL (by the way i would learn more about methods)
now i've a strange memory fatal error...
*** SYSTEM FATAL MESSAGE 6704 (DFMFRD)
LOGIC ERROR 2 IN NUMERIC PHASE OF SPARSE DECOMPOSITION.
USER ACTION: INCREASE MEMORY BY 30627744 WORDS.
0FATAL ERROR
but which memory has to be increased? ram? -_____________- could you help me?
RE: nonlinear buckling with restart
RE: nonlinear buckling with restart
Now another prolbem cames out:
*** SYSTEM FATAL MESSAGE 7340 (LNNHERR)
PROCESS ERROR REPORTED BY SUBROUTINE LNNP2CD (IER= -725)
USER INFORMATION: NUMBER OF COMPUTED EIGENVALUES EXCEED ALLOCATED STORAGE.
*** SYSTEM FATAL MESSAGE 7340 (LNNHERR)
WARNING REPORTED BY SUBROUTINE LNNDRVD (IER= 725)
USER INFORMATION: NUMBER OF COMPUTED EIGENVALUES EXCEED ALLOCATED STORAGE.
How much is allocated storage for this job? How i can change it?
Possible tath such simply test needs so much memory?
RE: nonlinear buckling with restart
RE: nonlinear buckling with restart
i think material properties are ok but i've found this error:
*** SYSTEM FATAL MESSAGE 3034 (LNNHERR)
INTERNAL FAILURE IN THE LANCZOS PROCEDURE:
M-ORTHOGONAL QR PROCEDURE FAILED TO CONVERGE. PROBABLE CAUSE:
MASS MATRIX IS INDEFINITE (MODES) OR STIFFNESS MATRIX IS INDEFINITE (BUCKLING).
USER ACTION: CONTACT MSC CLIENT SUPPORT.
*** fatal error no. -728 *** subroutine lnnp2cd
unrecoverable termination from lanczos iteration
internal error code: -6
where's the error in this model ?
thank you for the help