NX Nastran DMAP Programmer's Guide - Kxcad.net

1106
LAMX
Eigenvalue Table Editor
• Then eigenvalue, radians, and generalized stiffness are based on the
modified frequency and generalized mass:
radians: ωj = 2πf j
eigenvalue:
λ j
=
2
ω
j
generalized stiffness: Kj = λj mj • If R3j = – 1 then mode j is not copied to LAMAX.
• If R1j = 0 , R2j = 0 and R3j = 0 then mode j is copied from LAMA to
LAMAX without modification.
2. The FREQMASS matrix has three rows and one column for each mode. The
first row contains the frequencies and the third row contains the generalized
masses. The second row is null. Then eigenvalue, radians, and generalized
stiffness are computed as in Remark 3.
Number of Modes
f j
0.0
m j
3. In the LMAT matrix each row corresponds to a mode. Each column
corresponds to eigenvalue, radians, frequency, generalized mass, and
generalized stiffness.
Number of
Modes
5
λ i ω i f i M i k i
·
·
·
·
3