Subcases are really indipendent of each other in SOL400?

[Lorenzito]

Hi everybody

I'm trying to run a simple BEAM and BUSH model of about 200 DOF with 22000 subcases.
The analysis is a simple non-linear static analysis that I'm trying to solve by SOL400.
Even if in SOL 400 subcases are indipendent of each other as quoted in "Nastran Quick reference guide", I have noticed that if I isolate a single subcase and I solve it, the solution converges in fewer cycles than if the same subcase is among the 22000 subcases. That is a problem because it increases the overall time for solving the model.
I can't understand why that happens if the subcases are indipendent of each other.
Can anybody help me, please?

Thank you very much

LorenzoM

 

[nlgyro]

would it be possible for you to post your case-control for a few ( maybe 2 or 3) subcases?

 

[Lorenzito]

Please find attached a txt file with the first 5 subcases.

Thank you very much