Thermal load - structural-only analysis — Welcome to LS-DYNA Examples

In this example a steel frame is subjected to a thermal load which results in thermal expansion of the structure. The simulation is set up as ‘structural-only’ analysis using (static) implicit time integration. For the definition of the thermal load the keyword *LOAD_THERMAL_LOAD_CURVE is used. The temperature of the steel frame is initially at 20.0 °C and is ramped up to 200 °C. For the definition of the material properties a simple elastic model is used while the coefficient of thermal expansion for the parts is defined by *MAT_ADD_THERMAL_EXPANSION.

*BOUNDARY_SPC_SET
*CONTROL_ACCURACY
*CONTROL_IMPLICIT_GENERAL
*CONTROL_IMPLICIT_SOLUTION
*CONTROL_SOLUTION
*CONTROL_TERMINATION
*CONTROL_TIMESTEP
*DATABASE_BINARY_D3PLOT
*DATABASE_GLSTAT
*DATABASE_MATSUM
*DEFINE_CURVE
*ELEMENT_SHELL
*END
*INCLUDE
*KEYWORD
*LOAD_THERMAL_LOAD_CURVE
*MAT_ADD_THERMAL_EXPANSION
*MAT_ELASTIC
*NODE
*PART
*SECTION_SHELL
*SET_NODE_LIST_TITLE
*TITLE

*KEYWORD
$
$=============================CONTROL DEFINITIONS ==============================
$
*TITLE
Steel frame with thermal load - structural-only analysis
*CONTROL_SOLUTION
$     soln       nlq     isnan     lcint     lcacc     ncdcf
         0
*CONTROL_TIMESTEP
$   dtinit    tssfac      isdo    tslimt     dt2ms      lctm     erode     ms1st
                 0.9
*CONTROL_TERMINATION
$   endtim    endcyc     dtmin    endeng    endmas     nosol
       1.0
*CONTROL_ACCURACY
$      OSU       INN    PIDOSU      IACC
         1         4                   1
$--------1---------2---------3---------4---------5---------6---------7---------8
$ IMPLICIT CONTROL CARDS
$--------1---------2---------3---------4---------5---------6---------7---------8
*CONTROL_IMPLICIT_GENERAL
$   IMFLAG       DT0    IMFORM      NSBS       IGS     CNSTN      FORM    ZERO_V
         1       0.1                            
*CONTROL_IMPLICIT_SOLUTION
$   NSOLVR    ILIMIT    MAXREF     DCTOL     ECTOL     RCTOL     LSTOL    ABSTOL
        12                        0.0010   0.01000                       1.0E-20
$    DNORM    DIVERG     ISTIF   NLPRINT    NLNORM
         0         0         0         1         4
$
$================================ OUTPUTDATA ===================================
$
*DATABASE_BINARY_D3PLOT
$       dt
       0.1
*DATABASE_GLSTAT
$       dt
       0.1
*DATABASE_MATSUM
$       dt
       0.1
$
$============================== PART DEFINITIONS ===============================
$
*PART
$ title
column_1
$      pid     secid       mid     eosid      hgid      grav    adpopt      tmid
         1         1         1                                                  
*PART
$ title
bar
$      pid     secid       mid     eosid      hgid      grav    adpopt      tmid
         2         1         1                                                  
*PART
$ title
column_2
$      pid     secid       mid     eosid      hgid      grav    adpopt      tmid
         3         1         1
$
$============================= SECTION PROPERTIES ==============================
$
*SECTION_SHELL
$      SID    ELFORM      SHRF       NIP     PROPT   QR/IRID     ICOMP
         1       -16     0.833       5.0
$       t1        t2        t3        t4
       3.0       3.0       3.0       3.0
$
$====================== MECHANICAL MATERIAL PROPERTIES =========================
$
*MAT_ELASTIC
$#     MID        RO         E        PR        DA        DB         K
         1 7.8500E-9 2.1000E+5  0.300000     0.000     0.000         0
*MAT_ADD_THERMAL_EXPANSION 
$      PID      LCID      MULT     LCIDY     MULTY     LCIDZ     MULTZ
         1            12.0E-06 
         2            12.0E-06
         3            12.0E-06
$==================== THERMAL LOAD FOR STRUCTURAL ONLY ANALYSIS =================
$
*LOAD_THERMAL_LOAD_CURVE
$     lcid    lciddr
         1
*DEFINE_CURVE
$     LCID      SIDR      SCLA      SCLO      OFFA      OFFO
         1
$               time         temperature
                 0.0                 0.0
                 1.0               200.0
                 2.0               200.0
$
$====================== MECHANICAL BOUNDARY CONDITIONS =========================
$
*BOUNDARY_SPC_SET
$ nid/nsid       cid      dofx      dofy      dofz     dofrx     dofry     dofrz
         1                   1         1         1         1         1         1
*BOUNDARY_SPC_SET
$ nid/nsid       cid      dofx      dofy      dofz     dofrx     dofry     dofrz
         2                   1         1         1         1         1         1
$=======================NODE/ELEMENT/SET/SEGMENT DEFINTIONS ====================
*INCLUDE
geo.k
$
*SET_NODE_LIST_TITLE
fixing_1
$      sid       da1       da2       da3       da4    solver
         1 
$     nid1      nid2      nid3      nid4      nid5      nid6      nid7      nid8
         4         1         3         2                                        
*SET_NODE_LIST_TITLE
fixing_2
$      sid       da1       da2       da3       da4    solver
         2 
$     nid1      nid2      nid3      nid4      nid5      nid6      nid7      nid8
       161       163       164       162    
$--------1---------2---------3---------4---------5---------6---------7---------8
$
*END