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This problem demonstrates using LS-DYNA to solve for the unconstrained expansion of a block due to heating. The model consists of one 8 node brick element at an initial temperature of 10. The brick material is given a volumetric thermal generation rate. Explicit time integration is used for the structural calculations and implicit time integration is used for the thermal calculations. Implicit time integration is unconditionally stable and, therefore, a larger thermal time step can be taken.

Keywords

*CONTROL_SOLUTION
*CONTROL_TERMINATION
*CONTROL_THERMAL_SOLVER
*CONTROL_THERMAL_TIMESTEP
*CONTROL_TIMESTEP
*DATABASE_BINARY_D3PLOT
*DATABASE_GLSTAT
*ELEMENT_SOLID
*END
*INITIAL_TEMPERATURE_NODE
*KEYWORD
*MAT_ELASTIC_PLASTIC_THERMAL
*MAT_THERMAL_ISOTROPIC
*NODE
*PART
*SECTION_SOLID
*TITLE

Reduced Input

  $ Thermal Expansion of a Block
  $
  *KEYWORD
  $
  $=============================CONTROL DEFINITIONS ==============================
  $
  *TITLE
  thermal expansion of a block
  *CONTROL_SOLUTION
           2
  *CONTROL_THERMAL_SOLVER
           1         0         1
  *CONTROL_TIMESTEP
                                                 .01
  *CONTROL_THERMAL_TIMESTEP
           0       1.         .1
  *CONTROL_TERMINATION
          3.
  *DATABASE_BINARY_D3PLOT
         .01
  *database_glstat
  .03
  $
  $============================== PART DEFINITIONS ===============================
  $
  *PART
  $      PID     SECID       MID                                              TMID
  slab
           1         1         1                                                 1       
  $
  $============================= SECTION PROPERTIES ==============================
  $
  *SECTION_SOLID
  $    SECID    ELFORM
           1         1
  $
  $====================== MECHANICAL MATERIAL PROPERTIES =========================
  $
  *MAT_ELASTIC_PLASTIC_THERMAL
           1        1.
          0.       10.       20.       30.       40.       50.
      1.e+10    1.e+10    1.e+10    1.e+10    1.e+10    1.e+10
          .3        .3        .3        .3        .3        .3
      0.e-06   20.e-07   40.e-07   60.e-07   80.e-07  100.e-07
      1.e+20    1.e+20    1.e+20    1.e+20    1.e+20    1.e+20
          0.        0.        0.        0.        0.        0.
  $
  $======================== THERMAL MATERIAL PROPERTIES ==========================
  $
  *MAT_THERMAL_ISOTROPIC
           1        1.         0       10.
          1.        1.
  $
  $============================= NODE DEFINTIONS =================================
  $
  *NODE
         1              0.              0.              0.       7
         2              1.              0.              0.       5
         3              1.              1.              0.       3
         4              0.              1.              0.       6
         5              0.              0.              1.       4
         6              1.              0.              1.       2
         7              1.              1.              1.       0
         8              0.              1.              1.       1
  $
  $============================ ELEMENT DEFINITIONS ==============================
  $
  *ELEMENT_SOLID
         1       1       1       2       3       4       5       6       7       8
  $
  $============================ ELEMENT DEFINITIONS ==============================
  $
  *INITIAL_TEMPERATURE_NODE
           1       10.
           2       10.
           3       10.
           4       10.
           5       10.
           6       10.
           7       10.
           8       10.
  *END

Figures

image01.gif

image02.gif

Animated Result

Result

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