MPC (RBE2, RBE3) sol400 NASTRAN multi step analysis
MPC (RBE2, RBE3) sol400 NASTRAN multi step analysis
(OP)
Hi I'm an aeronautical engineer who work as stress analyst.
I've a problem with a non linear multi step analysis sol400 Nastran.
I've two non-linear steps, in the first there are preloaded bolts and some surface with friction.
In the second I added an inertial load.
There is a lamped mass which is linked with Rb2 and Rbe3 rigid element, to the structure.
If I run only the first step without rigid element and mass, There aren't problem. But with Mass the second step has some probleme, the mass loose its link with structure.
I've read that with nonlinear analysis, Rb2 and Bbe3 gives problems.
Is there someone who can help me please?
(I'm sorry for my english)
Thanks!
I've a problem with a non linear multi step analysis sol400 Nastran.
I've two non-linear steps, in the first there are preloaded bolts and some surface with friction.
In the second I added an inertial load.
There is a lamped mass which is linked with Rb2 and Rbe3 rigid element, to the structure.
If I run only the first step without rigid element and mass, There aren't problem. But with Mass the second step has some probleme, the mass loose its link with structure.
I've read that with nonlinear analysis, Rb2 and Bbe3 gives problems.
Is there someone who can help me please?
(I'm sorry for my english)
Thanks!





RE: MPC (RBE2, RBE3) sol400 NASTRAN multi step analysis
Spaceship!!
Aerospace Engineer, M.Sc. / Aircraft Stress Engineer
RE: MPC (RBE2, RBE3) sol400 NASTRAN multi step analysis
can you provide Nastran deck file (.dat)?
Jan
RE: MPC (RBE2, RBE3) sol400 NASTRAN multi step analysis
thanks very much
RE: MPC (RBE2, RBE3) sol400 NASTRAN multi step analysis
RE: MPC (RBE2, RBE3) sol400 NASTRAN multi step analysis
There are two problems:
I don't know why but the second step doesn't start from the stress of the first step.
In the output file I can visualize all results of the first step but only elemnt stress on the second.
I'think that the problems are RBE elm.
I need help please, attached the file.
thanks
RE: MPC (RBE2, RBE3) sol400 NASTRAN multi step analysis
Not so sure, but this is the only thing I can think of as I can't check your model at home without any FEA software.
In the company, they won't allow me to look into this. So I'm just text reading your bdf file.
Spaceship!!
Aerospace Engineer, M.Sc. / Aircraft Stress Engineer
RE: MPC (RBE2, RBE3) sol400 NASTRAN multi step analysis
Thanks for your help.
The second step is a linear analysis, I'm not sure that NLPARAM is necessary.
Do I have apply an NLPARM card in both steps?