Define cross-correlation
properties for random response loading.
This option is used to define the cross-correlation as part of the
definition of random loading for use in the
RANDOM RESPONSE analysis procedure. The
PSD-DEFINITION option is also needed to give the frequency function to be
used with the correlation definition.
Required parameter for TYPE=CORRELATED and TYPE=UNCORRELATED
PSD
Set this parameter equal to the name of the frequency function defined on
the
PSD-DEFINITION option to be associated with this correlation option.
Optional parameters
COMPLEX
Set COMPLEX=YES to include both real and imaginary terms in the
cross-correlation definition. The alternative is to include real terms only
using COMPLEX=NO (default).
INPUT
Set this parameter equal to the name of the alternate input file containing
the data lines for this option. See
Input Syntax Rules
for the syntax of such file names. If this parameter is omitted, it is assumed
that the data follow the keyword line.
TYPE
Set TYPE=CORRELATED (default) if all terms in the correlation matrix should be
included.
Set TYPE=UNCORRELATED if only diagonal terms should be used.
Set TYPE=MOVING NOISE for moving noise loading. In this case only one
CORRELATION option can be used in the step. The COMPLEX parameter cannot be used with TYPE=MOVING NOISE.
USER
Include this parameter to indicate that user subroutine
UCORR will be called to obtain the scaling factors for the
correlation matrix. If this parameter is included, the TYPE parameter can be set only to CORRELATED or UNCORRELATED.
Data lines for TYPE=CORRELATED or TYPE=UNCORRELATED
First
line
Load case number defined on the loading data lines.
Real part of scaling factor.
Imaginary part of scaling factor. (Only needed if COMPLEX=YES.)
Repeat this data line as often
as necessary to define the load cases and their associated scaling
factors.
Data lines if
the USER parameter is included
First line
Load case number defined on the loading data lines.
Repeat this data line as often
as necessary to define the load cases to be
correlated.
Data lines for TYPE=MOVING NOISE
First
line
Load case number defined on the loading data lines.
x-component of noise velocity.
y-component of noise velocity.
z-component of noise velocity.
Name of the power spectral density function, defined on the
PSD-DEFINITION option, for this noise source.
Repeat this data line as often
as necessary to define the random
loading.