Hello dears, I have performed a sol111 vibro-acoustic analysis, the sound pressure level was the desired output in pch format, after the analysis ended no pch file generated but the log file show that the analysis has performed successfully!! I examined the f06 file and saw that after the successful computation of normal modes and beginning the forced response calculation, this message is printed:
*** USER INFORMATION MESSAGE 6137 (DFMN)
INPUT MATRIX TO DECOMPOSITION HAS 1 SINGULARITIES.
SEE FOLLOWING MESSAGES FOR DETAILS.
*** USER INFORMATION MESSAGE 4158 (DFMSA)
---- STATISTICS FOR SPARSE DECOMPOSITION OF DATA BLOCK SCRATCH FOLLOW
NUMBER OF NEGATIVE TERMS ON FACTOR DIAGONAL = 0
MAXIMUM RATIO OF MATRIX DIAGONAL TO FACTOR DIAGONAL = 1.0E+15 AT ROW NUMBER
What is the cause of this failure and the solution?