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This is an example of a mass-spring model under base acceleration power spectral density excitation. *DATABASE_FREQUENCY_BINARY_D3PSD and *DATABASE_FREQUENCY_BINARY_D3RMS are used for post-processing of the results. Example 6.7 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Keywords
*CONTROL_IMPLICIT_EIGENVALUE
*CONTROL_IMPLICIT_GENERAL
*CONTROL_IMPLICIT_NONLINEAR
*CONTROL_TERMINATION
*DATABASE_BINARY_D3PLOT
*DATABASE_DEFORC
*DATABASE_FREQUENCY_BINARY_D3PSD
*DATABASE_FREQUENCY_BINARY_D3RMS
*DATABASE_HISTORY_NODE_SET
*DATABASE_NODOUT
*DEFINE_CURVE
*ELEMENT_DISCRETE
*ELEMENT_MASS
*ELEMENT_SHELL
*END
*FREQUENCY_DOMAIN_RANDOM_VIBRATION
*KEYWORD
*MAT_DAMPER_VISCOUS
*MAT_ELASTIC
*MAT_SPRING_ELASTIC
*NODE
*PART
*SECTION_DISCRETE
*SECTION_SHELL
*SET_NODE_LIST
*SET_SEGMENT
*TITLE
*KEYWORD
*TITLE
Spring subjected to base acceleration
*FREQUENCY_DOMAIN_RANDOM_VIBRATION
1 20
0.01
1 1 3 9810.0
0 3 1000
*DATABASE_FREQUENCY_BINARY_D3PSD
1
10. 100. 901
*DATABASE_FREQUENCY_BINARY_D3RMS
1
*CONTROL_IMPLICIT_EIGENVALUE
2 0
0 0 0 0 1
*CONTROL_IMPLICIT_GENERAL
1 1.000000
*CONTROL_IMPLICIT_NONLINEAR
1
0 0 0 0
0 0 0.000 1 2
*CONTROL_TERMINATION
1.000000
*DATABASE_HISTORY_NODE_SET
1
*DATABASE_DEFORC
0.001000 1
*DATABASE_NODOUT
0.001000 1
*DATABASE_BINARY_D3PLOT
0.100000
0
*PART
spring
1 1 2
*SECTION_DISCRETE
1
0.000 0.000
*MAT_SPRING_ELASTIC
2 6.4454
*PART
damper
2 1 1
*MAT_DAMPER_VISCOUS
1 0.0005129
*PART
plate
3 3 3
*SECTION_SHELL
3 2 1.000000 2 1 0 0 1
5.000000 5.000000 5.000000 5.000000
*MAT_ELASTIC
3 0.281793 2.908E+20 0.300000
*DEFINE_CURVE
1000
10.0000000 0.1
100.0000000 0.1
*SET_NODE_LIST
1
1 2
*SET_SEGMENT
1
1 3 4 5
3 1 11 10
1 12 13 5
1 12 16 11
*ELEMENT_SHELL
*ELEMENT_DISCRETE
*ELEMENT_MASS
*NODE
*END
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