NX Nastran DMAP Programmer's Guide - Kxcad.net

816
CEAD
Complex or unsymmetric eigenvalue analysis
CEAD Complex or unsymmetric eigenvalue analysis
Given that [M], [B] and [K] are mass, damping, and stiffness, solve the equation:
or
for the eigenvalues p and the associated right eigenvectors { φ}
or left eigenvectors
{ }
.
φ L
Format:
CEAD KXX,BXX,MXX,DYNAMIC,CASECC,VDXC,VDXR/
CPHX,CLAMA,OCEIG,LCPHX,CLAMMAT/
S,N,NEIGV/UNUSED2/SID/METH/EPS/ND1/ALPHAJ/OMEGAJ/
MAXBLK/IBLK/KSTEP/NDJ $
Input Data Blocks:
KXX Stiffness matrix. Usually KHH or KDD.
BXX Viscous damping matrix. Usually BHH or BDD.
MXX Mass matrix. Usually MHH or MDD.
DYNAMIC Table of Bulk Data entry images related to dynamics.
CASECC Table of Case Control command images.
Output Data Blocks:
[ M]p
2
( + [ B]p
+ [ K]
) { φ}
= 0
{ φL } T [ M]p
2
( + [ B]p
+ [ K]
) = { 0}
(Lanczos only)
Eq. 4-3
Eq. 4-4
VDXC Partitioning vector with 1.0 at rows corresponding to null columns in
KDD, BDD, and MDD.
VDXR Partitioning vector with 1.0 at rows corresponding to null rows in KDD,
BDD, and MDD.
CPHX Complex eigenvector matrix. Usually CPHH or CPHD.
CLAMA Complex eigenvalue summary table.
OCEIG Complex eigenvalue extraction report.