Energy — Welcome to LS-DYNA Examples

Home » Knowledge Base » Simple Examples » Examples Manual » Control » Energy

A copper bar strikes a wall.

Introduction

*CONTROL_ENERGY
Bar Impact
LS-DYNA Manual Section: *CONTROL_ENERGY

Example: Bar Impact

Filename: control_energy.bar-impact.k

Description:
A copper bar strikes a wall.

Model:
A 1/4 symmetry bar measures 0.32 cm in radius and 3.24 cm in length and
contains 972 hexahedron element. The bar starts at 0.0227 cm/ usec and stops at
0 cm/ usec. The calculation illustrates the energy balance where
E = KE + IE + HGE.

Input:
The hour glass energy is computed at a negligible cost. (*CONTROL_ENERGY)
The initial velocity for every node is set to -0.0227 except the nodes at z = 0.

Results:
The undeformed and deformed shape of the bar are shown. The total, kinetic,
internal and hourglass energies are also shown.

Keywords

*CONTROL_ENERGY
*CONTROL_HOURGLASS
*CONTROL_OUTPUT
*CONTROL_TERMINATION
*DATABASE_BINARY_D3PLOT
*DATABASE_BINARY_D3THDT
*DATABASE_GLSTAT
*DATABASE_HISTORY_NODE
*DATABASE_NODOUT
*DEFINE_BOX
*ELEMENT_SOLID
*END
*INITIAL_VELOCITY
*KEYWORD
*MAT_PLASTIC_KINEMATIC
*NODE
*PART
*SECTION_SOLID
*TITLE

Reduced Input

  *KEYWORD
  *TITLE
  bar impact
  $
  $  LSTC Example
  $
  $  Last Modified: September 12, 1997
  $
  $  Units: gm, cm, microsec, 1e+07 N, Mbar, 1e+07 N-cm
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $$$$  Control Ouput
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
  $
  *CONTROL_TERMINATION
  $   endtim    endcyc     dtmin    endneg    endmas
       82.10
  $
  *CONTROL_ENERGY
  $     hgen      rwen    slnten     rylen 
           2
  $
  *CONTROL_HOURGLASS
  $      ihq        qh
           4
  $
  *CONTROL_OUTPUT
  $    npopt    neecho    nrefup    iaccop     opifs    ipnint    ikedit
           0         0         0         0                   2      1000
  $
  $
  *DATABASE_BINARY_D3PLOT
  $       dt      lcdt
         5.0
  $
  *DATABASE_BINARY_D3THDT
  $       dt      lcdt
         1.0
  $
  *DATABASE_GLSTAT
  $       dt
         0.5
  $
  *DATABASE_NODOUT
  $  dt/cycl      lcdt
         0.5
  $
  *DATABASE_HISTORY_NODE
  $      id1       id2       id3       id4       id5       id6       id7       id8
        1333
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $$$$  Initial Conditions
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
  $
  $$$$  Nodes within box 2 are given an initial velocity in the neg z-direction.
  $$$$  These are all the nodes except for those on the bottom of the bar.
  $
  *INITIAL_VELOCITY
  $     nsid    nsidex     boxid
           0         0         2
  $       vx        vy        vz       vxe       vye       vze
         0.0       0.0   -0.0227       0.0       0.0       0.0
  $
  *DEFINE_BOX
  $    boxid       xmm       xmx       ymn       ymx       zmn       zmx
           2     -1.e6      1.e6     -1.e6      1.e6  0.50e-02      1.e6
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $$$$  Define Parts and Materials
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
  $
  *PART
  $      pid       sid       mid     eosid      hgid    adpopt
  Bar
           1         1         1
  $
  $
  *MAT_PLASTIC_KINEMATIC
  $      mid        ro         e        pr      sigy      etan      beta
           1     8.930      1.17     0.350     0.004     0.001       1.0
  $      src       srp        fs
         0.0       0.0       0.0
  $
  $
  *SECTION_SOLID
  $      sid    elform
           1         0
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $$$$  Define Nodes and Elements
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $$$$  Many nodes have boundary conditions to simulate symmetry.
  $
  $
  *END

Figures

image01.gif

image02.gif

Animated Result

Result

Download