Tube expansion by 2D analysis

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An elastic steel cone is inserted into a tube (σY = 580 MPa) with variable diameter using prescribed motion [16], see Figure 37. The analysis is performed using non-linear statics, and the control cards of control_cards_nonlin.key. Since the displacement in this case is quite large (400 mm), the solution control was modified, setting DNORM = 1 on *CONTROL_IMPLICIT_SOLUTION. A total of 809 axisymmetric solid elements (shell element formulation 15) are used. The example keyword file is run_2d.key (NOTE that this example should be run in smp/LS-DYNA double precision. From R14, mpp/LS-DYNA can also be used). The axial force-displacement curve is shown in Figure 38. Note that in axisymmetric analyses, reported forces should be multiplied by 2pi to obtain the total force.

Example Files: run_2d
NOTE! All examples are included in the Complete Guideline

Main Input

*KEYWORD 
$===============================================================================
$ Geometry
$===============================================================================
*INCLUDE
geo_2d001.key
$===============================================================================
$ Control and output cards
$===============================================================================
*INCLUDE
../INCLUDE_FILES/control_cards_nonlin.key
*INCLUDE
../INCLUDE_FILES/database_cards_static.key
*CONTROL_TERMINATION
$   ENDTIM    ENDCYC     DTMIN    ENDENG    ENDMAS
        1.
*DEFINE_CURVE_TITLE
Time stepping curve
       700
                  0.                0.01
                  1.                0.01
$===============================================================================
$ Contacts
$===============================================================================
*CONTACT_2D_AUTOMATIC_SURFACE_TO_SURFACE_MORTAR_ID
$#     cid                                                                 title
         1mandrel-cdb contact
$#    sids      sidm     sfact      freq        fs        fd        dc     membs
         1        30       1.0                 0.1    
$#  tbirth    tdeath       sos       som       nds       ndm       cof      init

$===============================================================================
$ Loading and boundary conditions
$===============================================================================
*BOUNDARY_SPC_SET
$#    nsid       cid      dofx      dofy      dofz     dofrx     dofry     dofrz
         2         0         0         1
*BOUNDARY_PRESCRIBED_MOTION_SET
$#    nsid       dof       vad      lcid        sf       vid     death     birth
        16         2         2         2     400.0        
*DEFINE_CURVE_TITLE
Motion
2,
0.,0.
1.,1.
2.,1.
$===============================================================================
$ Simulation title
$===============================================================================
*TITLE
Example of 2D analysis - tube deformation
*END