Random vibration with pressure load — Welcome to LS-DYNA Examples

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This is an example of of random vibration with pressure load. A rectangular plate is subjevted to power spectral density load. *DATABASE_FREQUENCY_ASCII_NODOUT_PSD, *DATABASE_FREQUENCY_ASCII_ELOUT_PSD and *DATABASE_FREQUENCY_BINARY_D3PSD are used for post-processing of the results. Example 6.1 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.

Keywords

```*BOUNDARY_SPC_SET
*CONTROL_IMPLICIT_EIGENVALUE
*CONTROL_IMPLICIT_GENERAL
*CONTROL_IMPLICIT_NONLINEAR
*CONTROL_SHELL
*CONTROL_TERMINATION
*DATABASE_BINARY_D3PLOT
*DATABASE_FREQUENCY_ASCII_ELOUT_PSD
*DATABASE_FREQUENCY_ASCII_NODOUT_PSD
*DATABASE_FREQUENCY_BINARY_D3PSD
*DATABASE_FREQUENCY_BINARY_D3RMS
*DATABASE_HISTORY_NODE_SET
*DATABASE_HISTORY_SHELL_SET
*DEFINE_CURVE
*ELEMENT_SHELL
*END
*FREQUENCY_DOMAIN_RANDOM_VIBRATION
*KEYWORD
*MAT_ELASTIC
*NODE
*PART
*SECTION_SHELL
*SET_NODE_LIST
*SET_SEGMENT
*SET_SHELL_LIST
*TITLE```

Reduced Input

```*KEYWORD
*TITLE
Benchmark example of rectangular plate for random vibration
*FREQUENCY_DOMAIN_RANDOM_VIBRATION
1        16     0.000     0.000         0
0.020000         0         0     0.000     0.000         0
2         1         0     0.000         0         0         0         0
0         0         0
1         2         3      2001         0         0         0         0
*DATABASE_FREQUENCY_ASCII_NODOUT_PSD
1.000000 10.000000      9001         0         0
*DATABASE_FREQUENCY_ASCII_ELOUT_PSD
1.000000 10.000000      9001         0         0
*DATABASE_FREQUENCY_BINARY_D3PSD
1
1.000000 10.000000        91         0         0
*DATABASE_FREQUENCY_BINARY_D3RMS
1
*CONTROL_IMPLICIT_EIGENVALUE
100     0.000         0     0.000         0     0.000         0     0.000
0         0         0         0         1
*CONTROL_IMPLICIT_GENERAL
1  1.000000         0         0         0         0         0         0
*CONTROL_IMPLICIT_NONLINEAR
1         0         0     0.000     0.000     0.000     0.000     0.000
0         0         0         0
0         0     0.000         1         2
*CONTROL_SHELL
20.000000         0        -1         0         2         2         1         0
0.000         1         0         0         0         0         0         0
0         0         0
*CONTROL_TERMINATION
1.000000         0     0.000     0.000     0.000
*DATABASE_BINARY_D3PLOT
0.000         0         0         0         0
0
*DATABASE_HISTORY_NODE_SET
6         0         0         0         0         0         0         0
*DATABASE_HISTORY_SHELL_SET
1         0         0         0         0         0         0         0
*BOUNDARY_SPC_SET
1         0         1         1         0         0         0         1
*SET_NODE_LIST
*BOUNDARY_SPC_SET
2         0         0         0         1         1         0         0
*SET_NODE_LIST
*BOUNDARY_SPC_SET
3         0         0         0         1         1         0         0
*SET_NODE_LIST
*BOUNDARY_SPC_SET
4         0         0         0         1         0         1         0
*SET_NODE_LIST
*BOUNDARY_SPC_SET
5         0         0         0         1         0         1         0
*SET_NODE_LIST
*SET_SEGMENT
*PART
shell_4p
1         1         1         0         0         0         0         0
*SECTION_SHELL
1        20  0.833000         3         3         0         0         0
0.050000  0.050000  0.050000  0.050000     0.000     0.000     0.000         0
*MAT_ELASTIC
1 8000.00002.0000E+11  0.300000     0.000     0.000         0
*DEFINE_CURVE
2001         0     0.000     0.000     0.000     0.000         0
0.1000000        10000.000000
40.0000000        10000.000000
*SET_NODE_LIST
6     0.000     0.000     0.000     0.000
3281         0         0         0         0         0         0         0
*SET_SHELL_LIST
1     0.000     0.000     0.000     0.000
3160      3161      3240      3241         0         0         0         0
*ELEMENT_SHELL
*NODE
*END```