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Deformable Contact Body, Fuselage - Wing connection, non-linear sol 400 NASTRAN

Deformable Contact Body, Fuselage - Wing connection, non-linear sol 400 NASTRAN

Deformable Contact Body, Fuselage - Wing connection, non-linear sol 400 NASTRAN

(OP)
Hey everybody,
Thanks for attencion.
I have specific issue, which I am not able to solve. If u would help me i will be gratefull.
It is my first post so, please to be lenient.

one part of my engineer thesis is to symulate contact condition.
To make it i use Patran 2012 with Nastran solver. (I try to solve it by nonlinear 400 solver)
I define 3 body ( wing part of hinge, fuselage part of hinge and bolt)
I define contact parameters to solid, (not to mesh)
I use linear performance of steel (I put denesity yield strength and posion ratio)
Constrain
(1,2,3)-translation (in solid face - part of fuselage hing)
extra constrain to block bolt (one direction - protrusion safe)
extra constrain to wing part of hinge (to block rotation in one direction- verticaly)

I make almost 40 solution to understand this problem ( I am beginieer in this topic)
And i have some issue.
When i try to make finally solution i have answer:

SER INFORMATION MESSAGE 6191 (nl3con)
*** UNABLE TO ACHIEVE CONVERGENCE FOR THE CURRENT INCREMENT OR TIME STEP, TRY TO FIND THE BEST SOLUTION ***
*** USER INFORMATION MESSAGE 6189 (nl3con)
*** BEST ATTAINABLE SOLUTION HAS BEEN FOUND ***
*** USER INFORMATION MESSAGE 4551 (nl3con)
*** UNABLE TO ACHIEVE CONVERGENCE FOR 4 CONSECUTIVE INCREMENTS OR TIME STEPS ***
*** USER FATAL MESSAGE 4551 (nl3con)
*** STOPPED PROBLEM DUE TO FAILED CONVERGENCE.

*** JOB DOES NOT CONVERGE AT THE CURRENT TIME STEP OR INCREMENT.
*** SOLUTION DIVERGES FOR SUBCASE 1 STEP 1.

whats more during just hinge and bolt (just 2 solids,solution) results are looking good.
I have problem to define contact between 3 solid parts.
If somebody of can put a little bit attention to my problem i will be gratefull.

P.S i use default setings for contact condition, without friction.

In attachmet:
-BDF of one test connection condition (to understand how it is working)
-Fo6 of this bdf

RE: Deformable Contact Body, Fuselage - Wing connection, non-linear sol 400 NASTRAN

(OP)
I forgot to say that i put several types of force (i try with pressure, nodal/point force, total load) nothing is working) My vector force is in (x,y) plane.

RE: Deformable Contact Body, Fuselage - Wing connection, non-linear sol 400 NASTRAN


try setting the nlparm card to something like:

$
nlparm,100,10,,iter,1,
,,1.-3,1.-5,-3,
$

Notice the "-3" on the continuation entry, this instructs Nastran to fatal out when convergence is not attained, and NOT try to find a "best solution"

RE: Deformable Contact Body, Fuselage - Wing connection, non-linear sol 400 NASTRAN

(OP)
Nlgyro, thanks for clue!

RE: Deformable Contact Body, Fuselage - Wing connection, non-linear sol 400 NASTRAN

(OP)
I made as u said and:
This is my bulk data entry:

$ Complex Eigenvalue Analysis, Direct Formulation, Database
SOL 400
CEND
$ Direct Text Input for Global Case Control Data
TITLE = MSC.Nastran job created on 05-Feb-15 at 18:12:01
SUBCASE 1
STEP 1
SUBTITLE=Default
ANALYSIS = NLSTATIC
NLPARM = 1
BCONTACT = ALLBODY
SPC = 2
LOAD = 2
DISPLACEMENT(SORT1,REAL)=ALL
SPCFORCES(SORT1,REAL)=ALL
STRESS(SORT1,REAL,VONMISES,BILIN)=ALL
BOUTPUT(SORT1,REAL)=ALL
$ Direct Text Input for this Subcase
BEGIN BULK
$ Direct Text Input for Bulk Data
PARAM PRTMAXIM YES
BCPARA 0 NLGLUE 1 NBODIES 3
PARAM LGDISP 1
$2345678$2345678$2345678$2345678$2345678$2345678$2345678$2345678$2345678
$NLPARM..1.......................FNT.............25.......PVA....NO
NLPARM..1........10..............iter....1
,...............1.-3....1.-5.....-3

*** USER INFORMATION MESSAGE 4551 (nl3con)
*** UNABLE TO ACHIEVE CONVERGENCE FOR 0 CONSECUTIVE INCREMENTS OR TIME STEPS ***
*** USER FATAL MESSAGE 4551 (nl3con)
*** STOPPED PROBLEM DUE TO FAILED CONVERGENCE.

*** JOB DOES NOT CONVERGE AT THE CURRENT TIME STEP OR INCREMENT.
*** SOLUTION DIVERGES FOR SUBCASE 1 STEP 1

During just two solid analise everything is looking good.
When i tried to sol 101 i got results, but i guess it will be not good idea to use it to put to the raport?
I got some extra stress in place i should not have

RE: Deformable Contact Body, Fuselage - Wing connection, non-linear sol 400 NASTRAN


That is expected when the MAXDIV field points to -3.

It means you still need to debug your model, before the results can be published.

Without having seen your model and knowing what you're trying to simulate, I don't think I can go any further.

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