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Problem description: An explosive material is placed inside of a sphere. The explosive is lit, expands, and impacts the sphere. The sphere expands, reaches yield, seam lines fail (failure strain 0.2) and fragments fly apart. Due to use of high explosives time step must be scaled down for stability.

Keywords

*CONTACT_SLIDING_ONLY
*CONTROL_ENERGY
*CONTROL_OUTPUT
*CONTROL_TERMINATION
*CONTROL_TIMESTEP
*DATABASE_BINARY_D3PLOT
*DATABASE_BINARY_D3THDT
*DATABASE_EXTENT_BINARY
*DATABASE_GLSTAT
*DATABASE_MATSUM
*DATABASE_RCFORC
*ELEMENT_SHELL
*ELEMENT_SOLID
*END
*EOS_JWL
*INITIAL_DETONATION
*KEYWORD
*MAT_HIGH_EXPLOSIVE_BURN
*MAT_PLASTIC_KINEMATIC
*NODE
*PART
*SECTION_SHELL
*SECTION_SOLID
*SET_SEGMENT
*TITLE

Reduced Input

  *KEYWORD
  *TITLE
  an exploding sphere
  $
  $  John D. Reid  1/31/00 - original model obtained from K. Bui (LSTC) - 4/22/97
  $
  $  Units: unknown - possibly gm, cm, micros, 1E7N, Mbar, 1E7N-cm
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $$$$  Control Ouput
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
  $
  *CONTROL_TERMINATION
  $   endtim    endcyc     dtmin    endeng    endmas
        50.0
  $
  *CONTROL_TIMESTEP
  $   dtinit    tssfac      isdo    tslimt     dt2ms      lctm     erode     ms1st
                  0.30
  $
  *CONTROL_ENERGY
  $     hgen      rwen    slnten     rylen
           2         2         2
  $
  *CONTROL_OUTPUT
  $    npopt    neecho    nrefup    iaccop     opifs    ipnint    ikedit
           1         3
  $
  $
  *DATABASE_BINARY_D3PLOT
  $       dt
         1.0
  $
  $*DATABASE_EXTENT_BINARY
  $    neiph     neips    maxint    strflg    sigflg    epsflg    rltflg    engflg
  $
  $   cmpflg    ieverp    beamip
  $                   1
  $
  *DATABASE_BINARY_D3THDT
  $       dt
    999999.9
  $
  *DATABASE_GLSTAT
  $       dt
         0.1
  $
  *DATABASE_MATSUM
  $       dt
         0.1
  $
  *DATABASE_RCFORC
  $       dt
         0.1
  $
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $$$$  Boundary and Initial Conditions
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
  $
  *INITIAL_DETONATION
  $      pid         x         y         z        lt
           2      0.00      0.00      0.00      0.00
  $
  $   pid = 2  Part ID of high explosive material to be lit.
  $   x,y,z    Coordinate of detonation point.
  $   lt = 0   Lighting time.
  $
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $$$$  Define Parts and Materials
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
  $ 
  $$$ Part    1    shell: sphere
  $
  $$$ Part    2    solid: high explosive
  $
  *PART
  $      pid       sid       mid     eosid      hgid      grav    adpopt
  sphere
           1         1         1
  high explosive
           2         2         2         2
  seams
           3         1         3
  $ 
  $ 
  $$$$  Materials
  $
  *MAT_PLASTIC_KINEMATIC
  $
  $      mid        ro         e        pr      sigy      etan      beta
           1     7.874      2.07      0.28      0.15     0.136         0
  $
  $      src       srp        fs
          40         5
  $
  *MAT_PLASTIC_KINEMATIC
  $
  $      mid        ro         e        pr      sigy      etan      beta
           3     7.874      2.07      0.28      0.15     0.136         0
  $
  $      src       srp        fs
          40         5       0.2
  $
  $
  *MAT_HIGH_EXPLOSIVE_BURN
  $...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
  $      mid        ro         d       pcj      beta         k         g      sigy
           2     1.717     0.798     0.290
  $
  $   mid = 2      Material ID
  $   ro  = 1.717  mass density
  $   d   = 0.798  detonation velocity
  $   pcj = 0.290  Chapman-Jouget pressure
  $
  $
  $$$$  Sections
  $
  *SECTION_SHELL
  $      sid    elform      shrf       nip     propt   qr/irid     icomp
           1
  $       t1        t2        t3        t4      nloc
        0.50      0.50      0.50      0.50
  $
  *SECTION_SOLID
  $      sid    elform
           2         1
  $
  $
  $
  *EOS_JWL
  $    eosid         A         B        r1        r2      omeg        Eo        Vo
           2 5.2421999   0.07678 4.2000003      1.10     0.340     0.085      1.00
  $
  $  Defines the pressure in the solid elements as a function
  $  of the relative volume and internal energy.
  $
  $  Eo = 0.085  initial internal energy
  $  Vo = 1.000  initial relative volume
  $  A, B, r1, r2, omeg = parameters of equation of state
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $$$$  Contact
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $  *CONTACT_SLIDING_ONLY     -  defined at end of model
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $$$$  Define Nodes and Elements
  $
  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
  $
  $...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
  $
  *CONTACT_SLIDING_ONLY
  $HMNAME GROUPS       1ContSlide_1                     
  $HMCOLOR GROUPS       1       1
           1         2         0         0
  
  
  *SET_SEGMENT
           1
  *SET_SEGMENT
           2
  $
  *END

Figures

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Animated Result

Result

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