LSDYNA FRF for a cantilever with pre-stress condition

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This cantilever model shows how to run FRF examples with pre-stress condition. The first file shows the usual *FREQUENCY_DOMAIN_FRF setup without pre-stress. In the second file *INTERFACE_SPRINGBACK_LSDYNA is used to create a dynain-file, which is then the basis for pre-stress analysis with *INCLUDE. In addition, usage of intermittent eigenvalue analysis is shown. Example 4.2 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.

Keywords

*BOUNDARY_SPC_NODE
*CONTROL_IMPLICIT_GENERAL
*CONTROL_IMPLICIT_NONLINEAR
*CONTROL_TERMINATION
*DATABASE_BINARY_D3PLOT
*DEFINE_CURVE
*ELEMENT_SHELL
*END
*INTERFACE_SPRINGBACK_LSDYNA
*KEYWORD  
*LOAD_NODE_POINT
*MAT_ELASTIC
*NODE
*PART
*SECTION_SHELL
*SET_PART_LIST
*TITLE


*CONTROL_IMPLICIT_EIGENVALUE
*CONTROL_IMPLICIT_GENERAL
*CONTROL_IMPLICIT_NONLINEAR
*CONTROL_TERMINATION
*DATABASE_BINARY_D3PLOT
*DEFINE_CURVE
*END
*FREQUENCY_DOMAIN_FRF
*INCLUDE
*KEYWORD  
*MAT_ELASTIC
*PART
*SECTION_SHELL
*TITLE


*BOUNDARY_SPC_NODE
*CONTROL_IMPLICIT_EIGENVALUE
*CONTROL_IMPLICIT_GENERAL
*CONTROL_IMPLICIT_NONLINEAR
*CONTROL_TERMINATION
*DATABASE_BINARY_D3PLOT
*DEFINE_CURVE
*ELEMENT_SHELL
*END
*FREQUENCY_DOMAIN_FRF
*KEYWORD  
*LOAD_NODE_POINT
*MAT_ELASTIC
*NODE
*PART
*SECTION_SHELL
*TITLE

Reduced Input

*KEYWORD  
*TITLE
cantilevered shell strip w/ end force
*SET_PART_LIST
         8     0.000     0.000     0.000     0.000          
         1         0         0         0         0         0         0         0
*INTERFACE_SPRINGBACK_LSDYNA
         8         0         0
*CONTROL_IMPLICIT_GENERAL
         1   0.01000         2         0         1         0         0         0
*CONTROL_IMPLICIT_NONLINEAR
         2         0         0     0.000     0.000     0.000     0.000     0.000
         2         1         0         2
         0         0     0.000         1         2
*CONTROL_TERMINATION
  1.000000         0     0.000     0.000     0.000
*DATABASE_BINARY_D3PLOT
  1.000000         0         0         0         0
         0
*BOUNDARY_SPC_NODE
         1         0         1         1         1         1         1         1
        17         0         1         1         1         1         1         1
        33         0         1         1         1         1         1         1
*LOAD_NODE_POINT
        16         2        98  -0.50000         0         0         0         0
        32         2        98  -1.00000         0         0         0         0
        48         2        98  -0.50000         0         0         0         0
*PART
cantilevered shell
         1         1         1         0         0         0         0         0
*SECTION_SHELL
         1        16   0.83333         3         1         0         0         1
  0.100000  0.100000  0.100000  0.100000     0.000     0.000     0.000         0
*MAT_ELASTIC
         1 7.0000E-4 3.0000E+7  0.300000     0.000     0.000         0
*DEFINE_CURVE
        11         0     0.000     0.000     0.000     0.000         0
               0.000         100.0000000
           1.0000000         100.0000000
*DEFINE_CURVE
        98         0     0.000     0.000     0.000     0.000         0
               0.000               0.000
           0.0500000          50.0000000
           1.0000000          50.0000000
*ELEMENT_SHELL
*NODE
*END


*KEYWORD  
*TITLE
cantilevered shell strip w/ end force
*FREQUENCY_DOMAIN_FRF
        25         0        -2         3         0   20000.0
      0.01
        32         0         2         1
      100.    10000.       100
*CONTROL_IMPLICIT_EIGENVALUE
       100     0.000         0     0.000         0     0.000         2     0.000
         0         0         0         0
*INCLUDE
dynain
*CONTROL_IMPLICIT_GENERAL
         1   0.00000         2         0         1         0         0         0
*CONTROL_IMPLICIT_NONLINEAR
         1         0         0     0.000     0.000     0.000     0.000     0.000
         2         1         0         2
         0         0     0.000         1         2
*CONTROL_TERMINATION
  0.000000         0     0.000     0.000     0.000
*DATABASE_BINARY_D3PLOT
  1.000000         0         0         0         0
         0
*PART
cantilevered shell
         1         1         1         0         0         0         0         0
*SECTION_SHELL
         1        16   0.83333         3         1         0         0         1
  0.100000  0.100000  0.100000  0.100000     0.000     0.000     0.000         0
*MAT_ELASTIC
         1 7.0000E-4 3.0000E+7  0.300000     0.000     0.000         0
*DEFINE_CURVE
        11         0     0.000     0.000     0.000     0.000         0
               0.000         100.0000000
           1.0000000         100.0000000
*DEFINE_CURVE
        98         0     0.000     0.000     0.000     0.000         0
               0.000               0.000
           0.0500000          50.0000000
           1.0000000          50.0000000
*END


*KEYWORD  
*TITLE
cantilevered shell strip w/ end force
*FREQUENCY_DOMAIN_FRF
        25         0        -2         3         0   20000.0
      0.01
        32         0         2         1
      100.    10000.       100
*CONTROL_IMPLICIT_EIGENVALUE
       -11     0.000         0     0.000         0     0.000         2     0.000
         0         0         0         0
*CONTROL_IMPLICIT_GENERAL
         1   0.01000         2         0         1         0         0         0
*CONTROL_IMPLICIT_NONLINEAR
         2         0         0     0.000     0.000     0.000     0.000     0.000
         2         1         0         2
         0         0     0.000         1         2
*CONTROL_TERMINATION
  1.000000         0     0.000     0.000     0.000
*DATABASE_BINARY_D3PLOT
  1.000000         0         0         0         0
         0
*BOUNDARY_SPC_NODE
         1         0         1         1         1         1         1         1
        17         0         1         1         1         1         1         1
        33         0         1         1         1         1         1         1
*LOAD_NODE_POINT
        16         2        98  -0.50000         0         0         0         0
        32         2        98  -1.00000         0         0         0         0
        48         2        98  -0.50000         0         0         0         0
*PART
cantilevered shell
         1         1         1         0         0         0         0         0
*SECTION_SHELL
         1        16   0.83333         3         1         0         0         1
  0.100000  0.100000  0.100000  0.100000     0.000     0.000     0.000         0
*MAT_ELASTIC
         1 7.0000E-4 3.0000E+7  0.300000     0.000     0.000         0
*DEFINE_CURVE
        11         0     0.000     0.000     0.000     0.000         0
               0.000         100.0000000
           1.0000000         100.0000000
*DEFINE_CURVE
        98         0     0.000     0.000     0.000     0.000         0
               0.000               0.000
           0.0500000          50.0000000
           1.0000000          50.0000000
*ELEMENT_SHELL
*NODE
*END

FRF for a cantilever with pre-stress condition — Welcome to LS-DYNA Examples

Keywords

Reduced Input

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