Nastran error-Too many restarts

[Bharathsf]

Hi,
I am getting the nastran error message
"SYSTEM FATAL MESSAGE 6724 (SB11RD)
TOO MANY RESTARTS."

I have no idea on how to continue,Please help.

Bharat

 

[brailos]

29311 Iterative Solver - SITDR2, SOLVIT, ITER - UFM 6724 (SB1RM)

The iterative solver may fail with the message:

USER INFORMATION MESSAGE 6447 (SITDR2)
ITERATIVE SOLVER DIAGNOSTIC OUTPUT

EPS : 1.00000E-06
BICWELL PRECONDITIONING

USER FATAL MESSAGE 6724 (SB1RM)
TOO MANY RESTARTS.
USER ACTION: INCREASE IPAD VALUE ON BULK DATA CARD ITER.

0FATAL ERROR

Avoidance: This message may be caused by a negative term on the factor
diagonal.. A potential cause for getting a negative diag. term is that the
matrix is ill-conditioned. The error may be avoided by increasing the IPAD
parameter on the ITER entry. Another possibility is- to use BICILL instead of
BICWELL.



Hope it helps