LS DYNA Simulation where both impactor and target are ALE [HELP REQUEST]

- July 24, 2024 at 10:26 pm
  
  JASH RANA
  Subscriber
  
  Hi Forum,
  
  I am trying to run a simulation where I have an aluminum particle impacting an aluminum substrate. I want both as ALE since they experience high distortion in lagrangian as well as premature termination. I am not sure if my current implmentation is correct. When I run the simulation both my particle and substrate dissapear and I get this warning:
  
  *** Warning 40864 (SOL+864)
  Segment based contact stiffness was reduced due to
  an increasing solution time step. The new time step for
  the stiffness calculation is 1.2952E-08
  And this error:
  *** Error 40509 (SOL+509)
  negative volume in solid element # 193650 cycle 688
  *** Error 40509 (SOL+509)
  negative volume in solid element # 193650 cycle 688
  
  Any help on implementing ALE into my model would be much appreciated. Thanks in advance. I have attached my model for your reference.
  Keyword File
- July 25, 2024 at 2:16 pm
  
  Ian Do
  Ansys Employee
  
  Hi Jash,
  ELFORM=5 is obsolete. Please use ELFORM=11. And you must provide the extra empty ALE space around the mat that is deforming. This space can be filled with air or mat_vacuum. Before using ALE, it would save time if you can review the ALE class on ANSYS Learning Hub (ALH). There are may examples available there also. What you see is likely the result of locally very strong force combining with large dt that invert the elm. You may need to look at tuning either one or both.
  Regards,
  Ian Do
- July 25, 2024 at 3:35 pm
  
  JASH RANA
  Subscriber
  
  Hi Ian,
  
  Thank you for the reply. I don't believe my institution has a subscribtion to ALH. Do I need to provide empty space for both the substrate and particle? or just the particle? Do you have an example keyword file that contains a similar problem to mine (impactor and target both ALE)?
  Regards,
  Jash
- July 31, 2024 at 9:28 pm
  
  Ian Do
  Ansys Employee
  
  Hi Jash,
  This may be similar (I can't attach a file so i just put it here.) Anyway, ALE is difficult and you likely need a class. I can't teach it through this communication channel.
  *KEYWORD
  *TITLE
  saleimpact3b.k = kg-m-s-K - pls assume fictitious data & put in your own referened data.
  $===============================================================================
  *COMMENT
  Model Summary:
  H4 = AMMG1 = impactor
  H2 = AMMG2 = top plate
  H1 = AMMG3 = bottom plate
  $===============================================================================
  $ [ ] EXECUTION CONTROLS
  $===============================================================================
  *CONTROL_TERMINATION
  $# endtim endcyc dtmin endeng endmas nosol
  $ 2.5E-4 0 0.0 0.0 0.0 0
  10.0E-4 0 0.0 0.0 0.0 0
  *CONTROL_TIMESTEP
  $# dtinit tssfac isdo tslimt dt2ms lctm erode ms1st
  0.0 0.7 0 0.0 0.0 0 0 0
  $ 0.0 0.2 0 0.0 0.0 0 0 0
  $# dt2msf dt2mslc imscl unused unused rmscl
  0.0 0 0 0.0
  *CONTROL_CONTACT
  $# slsfac rwpnal islchk shlthk penopt thkchg orien enmass
  0.1 0.0 1 0 1 0 1 0
  $# usrstr usrfrc nsbcs interm xpene ssthk ecdt tiedprj
  0 0 10 0 4.0 0 1 0
  $# sfric dfric edc vfc th th_sf pen_sf
  0.0 0.0 0.0 0.0 0.0 0.0 0.0
  $# ignore frceng skiprwg outseg spotstp spotdel spothin
  0 0 0 0 0 0 0.0
  $# isym nserod rwgaps rwgdth rwksf icov swradf ithoff
  0 0 1 0.0 1.0 0 0.0 0
  $# shledg pstiff ithcnt tdcnof ftall unused shltrw
  0 0 0 0 0 0.0
  *CONTROL_CPU
  $# cputim
  0.0
  *CONTROL_ENERGY
  $# hgen rwen slnten rylen
  2 2 2 2
  *CONTROL_OUTPUT
  $# npopt neecho nrefup iaccop opifs ipnint ikedit iflush
  0 0 0 0 0.0 0 100 9000
  $# iprtf ierode tet10s8 msgmax ipcurv gmdt ip1dblt eocs
  0 0 2 50 0 0.0 0 0
  $# tolev newleg frfreq minfo solsig msgflg cdetol
  2 0 1 0 0 0 10.0
  $# phschng demden
  0 0
  $===============================================================================
  $ [ ] OUTPUT CONTROLS
  $===============================================================================
  *DATABASE_BINARY_D3PLOT
  $# dt lcdt beam npltc psetid
  1.0E-5 0 0 100 0
  $# ioopt
  0
  $===============================================================================
  $ [ ] |PART_ID|SECTION_ID|MAT_ID|EOS_ID|HG_ID|GRAV|ADPOPT|THERM_MID| DEFINITIONS
  $===============================================================================
  *PART
  H1 = AMMG4 = Thick bottom Plate - A36 SS -Johnson Cook - kg-m-s-K
  $# pid secid mid eosid hgid grav adpopt tmid
  $ 1 1 1 1 0 0 0 0
  1 1 12 12 0 0 0 0
  *SECTION_ALE2D
  $ secid1 aleform aet elform
  1 11 14
  *MAT_JOHNSON_COOK
  $# mid ro g e pr dtf vp rateop
  1 7890.07.80000E102.00000E11 0.26 0.0 0.0 0.0
  $# a b n c m tm tr epso
  2.861000E85.000000E8 0.2282 0.022 0.917 1811.0 293.15 1.0
  $# cp pc spall it d1 d2 d3 d4
  481.0 0.0 2.0 0.0 0.0 0.0 0.0 0.0
  $# d5 c2/p erod efmin
  0.0 0.0 01.00000E-6
  *EOS_GRUNEISEN
  $# eosid c s1 s2 s3 gamao a e0
  1 4569.0 1.49 0.0 0.0 2.17 0.0 0.0
  $# v0
  0.0
  $-------------------------------------------------------------------------------
  *PART
  H2 = AMMG3 = top Plate - Lexan-Johnson Cook - kg-m-s-K
  $# pid secid mid eosid hgid grav adpopt tmid
  $ 2 1 2 2 0 0 0 0
  2 1 12 12 0 0 0 0
  $ 2 1 22 0 0 0 0 0
  *MAT_JOHNSON_COOK
  $# mid ro g e pr dtf vp rateop
  2 1190.07.860000E82.540000E9 0.344 0.0 0.0 0.0
  $# a b n c m tm tr epso
  7.580000E76.890000E7 1.004 0.0 1.85 533.0 293.15 1.0
  $# cp pc spall it d1 d2 d3 d4
  1250.0 0.0 2.0 0.0 0.0 0.0 0.0 0.0
  $# d5 c2/p erod efmin
  0.0 0.0 01.00000E-6
  *EOS_GRUNEISEN
  $# eosid c s1 s2 s3 gamao a e0
  2 1933.0 1.42 0.0 0.0 0.61 0.0 0.0
  $# v0
  0.0
  $-------------------------------------------------------------------------------
  *MAT_ELASTIC
  $ MID RHO E PR DA DB K
  22 1190.0 2.54E9 0.344
  $-------------------------------------------------------------------------------
  *MAT_JOHNSON_COOK
  $ MID RO G E PR DTF VP - Cu
  12 8960.0 0.460E11 0.0 0.34
  $ A B n C m Tm Tr eps0
  90.0E6 292.0E6 0.310 0.0250 1.09 1356.0 293.00 1.0
  $ Cp Pc Spall IT d1 d2 d3 d4
  383.0 -1.2E6 2.0 0.000 0.540 4.89 3.03 0.0140
  $ d5
  1.12
  *EOS_GRUNEISEN
  $ EOSID C S1 S2 S3 GAMMA A E0
  12 3940.0 1.489 0.0 0.0 2.020 0.47 0.0
  $ VO
  0.0
  $-------------------------------------------------------------------------------
  *PART
  H4 = AMMG2 = Impactor - JOHNSON_HOLMQUIST_CERAMICS - Float glass-Borosilicate
  $# pid secid mid eosid hgid grav adpopt tmid
  $ 4 1 4 0 0 0 0 0
  4 1 14 14 0 0 0 0
  $ 4 1 24 0 0 0 0 0
  *MAT_JOHNSON_HOLMQUIST_CERAMICS
  $# mid ro g a b c m n
  4 2500.03.04000E10 0.93 0.88 0.003 0.35 0.77
  $# epsi t sfmax hel phel beta
  1.01.500000E82.975000E95.950000E92.920000E9 1.0
  $# d1 d2 k1 k2 k3 fs
  0.053 0.854.54000E10-1.3800E112.90000E11 0.0
  *EOS_GRUNEISEN
  $# eosid c s1 s2 s3 gamao a e0
  4 4710.0 1.0 0.0 0.0 1.0 0.0 0.0
  $# v0
  0.0
  $-------------------------------------------------------------------------------
  *MAT_ELASTIC
  $ MID RHO E PR DA DB K
  24 7840.0 210.0e+9 0.3
  $---5----0----5----0----5----0----5----0----5----0----5----0----5----0----5----0
  *MAT_JOHNSON_COOK
  $ MID RHO G E PR DTF VP - SS
  14 7840.0 80.0E+9 210.0e+9 0.3 0.0 0.0
  $ A B n C m Tm Tr EPSO
  792.19e6 509.51e6 0.26 0.014 1.03 1793.15 298.15 1
  $ Cp PC spall IT D1 D2 D3 D4
  477 -1.0e8 0.0 0.0 -8.0e-1 2.1e00 -5.0e-1 2.0e-3
  $ D5
  6.1e-1
  *EOS_GRUNEISEN
  14 4.570E3 1.49 0.0 0.0 1.930 0.0 0.0
  $ VO
  0.0
  $-------------------------------------------------------------------------------
  *PART
  H5 = AMMG1 = air (Kg-m-s-K) @ T = 25 C
  $# pid secid mid eosid hgid grav adpopt tmid
  $ 5 1 5 5 0 0 0 0
  5 1 6 0 0 0 0 0
  *MAT_NULL
  $ MID RO PC MU TEROD CEROD YMBEAM PRBEAM
  5 1.1845 -1.0 1.8444E-5 0.0 0.0 0.0 0.0
  *EOS_LINEAR_POLYNOMIAL
  $ EOSID C0 C1 C2 C3 C4 C5 C6
  5 0.0 0 0 0 0.4 0.4 0
  $ E0 V0
  2.533125E5 1.0
  $---5----0----5----0----5----0----5----0----5----0----5----0----5----0----5----0
  *COMMENT
  PART
  H6 = AMMG5 = vacuum
  $# pid secid mid eosid hgid grav adpopt tmid
  6 1 6 0 0 0 0 0
  *MAT_VACUUM
  $ MID RO PC MU TEROD CEROD YMBEAM PRBEAM
  6 1.0E-06
  $===============================================================================
  $ SALE
  $===============================================================================
  *ALE_STRUCTURED_MESH
  $# mshid dpid nbid ebid tdeath
  11 11 20001 20001
  $# cpidx cpidy cpidz nid0 lcsid
  101 102
  $-------------------------------------------------------------------------------
  *ALE_STRUCTURED_MESH_CONTROL_POINTS
  $# cpid sfo offo
  101 1.0 0.0
  $# n x ratio
  1 0.0
  201 0.4
  $ 401 0.4
  *ALE_STRUCTURED_MESH_CONTROL_POINTS
  $# cpid sfo offo
  102 1.0 0.0
  $# n x ratio
  1 0.0
  186 0.370
  $ 371 0.370
  $===============================================================================
  *CONTROL_ALE
  $# dct nadv meth afac bfac cfac dfac efac
  -1 1 2 -1.0 0.0 0.0 0.0 0.0
  $# start end aafac vfact prit ebc pref nsidebc
  $ 0.0 0.0 0.0 0.0 0 0 101325.0 0
  0.0 0.0 0.0 0.0 0 0 0.0 0
  $# ncpl nbkt imascl checkr beamin mmgpref pdifmx dtmufac
  1 50 0 0.0 0.0 0 0.0 0.0
  $# optimpp ialedr bndflx minmas
  0 0 01.00000E-5
  $-------------------------------------------------------------------------------
  *ALE_MULTI-MATERIAL_GROUP
  $# sid idtype gpname
  5 1 1airvac
  4 1 2impactor
  2 1 3topplate
  1 1 4botplate
  $ 6 1 5vac
  $-------------------------------------------------------------------------------
  *ALE_STRUCTURED_MESH_VOLUME_FILLING
  $# mshid unused ammgto unused nsample unused unused vid
  11 1 4 0
  $# geom in/out e1 e2 e3 e4 e5
  ALL 0 0.0 0.0 0.0 0.0 0.0
  $-------------------------------------------------------------------------------
  *ALE_STRUCTURED_MESH_VOLUME_FILLING
  $ MSHID notused AMMGTO notused NSAMPLE notused notused VID
  11 2 4 51
  $ 11 2 4
  $ geom in/out E1=CTRNID E2=rx E3=ry R4=rz E5=lcsid
  ELLIPSOID 0 11 0.05 0.05 0.00 0
  *DEFINE_VECTOR
  $ vid xt=velx yt=vely zt=velz
  51 0.0 -50.0 0.0
  *NODE
  $ NID X Y Z TC RC
  11 0.0 0.31 0.0
  $-------------------------------------------------------------------------------
  $ center: Xc=0.0, Yc=0.31, Zc=0.0 , R=0.05
  $===============================================================================
  *ALE_STRUCTURED_MESH_VOLUME_FILLING
  $ MSHID notused AMMGTO notused NSAMPLE notused notused VID
  11 3 4
  $ GEOM IN/OUT E1=BOXID E2 E3 E4 E5
  BOXCOR 0 2
  *DEFINE_BOX
  $ BOXID XMN XMX YMN YMX ZMN ZMX
  2 0.0 0.4 0.2 0.256 0.0 0.01
  $-------------------------------------------------------------------------------
  $ SALE mesh box: (0.0,0.2,0.0)-(0.4,0.256,0.0), dx=0.002
  $===============================================================================
  *ALE_STRUCTURED_MESH_VOLUME_FILLING
  $ MSHID notused AMMGTO notused NSAMPLE notused notused VID
  11 4 4
  $ GEOM IN/OUT E1=BOXID E2 E3 E4 E5
  BOXCOR 0 3
  *DEFINE_BOX
  $ BOXID XMN XMX YMN YMX ZMN ZMX
  3 0.0 0.4 0.0 0.2 0.0 0.01
  $-------------------------------------------------------------------------------
  $ SALE mesh box: (0.0,0.0,0.0)-(0.4,0.2,0.0), dx=0.002
  $-------------------------------------------------------------------------------
  *SET_MULTI
  201
  1
  *SET_MULTI
  202
  2
  $-------------------------------------------------------------------------------
  *DEFINE_CURVE
  $# lcid sidr sfa sfo offa offo dattyp lcint
  2 0 1.0 1.0
  $# a1 o1
  0.0000 0.0
  0.1000 1.e7
  $===============================================================================
  $ [ ] BC's + IC's + BODY LOADS + FORCE FIELDS
  $===============================================================================
  *BOUNDARY_SPC_SET
  $ nodeset1 cid dofx dofy dofz dofrx dofry dofrz
  1 0 1 1 1
  2 0 1 1 1
  $-------------------------------------------------------------------------------
  *SET_NODE_GENERAL
  $ SID
  1
  $ OPTION MSHID XMN XMX YMN YMX ZMN ZMX
  SALEFAC 11 1
  $-------------------------------------------------------------------------------
  *SET_NODE_GENERAL
  $ SID
  2
  $ OPTION MSHID XMN XMX YMN YMX ZMN ZMX
  SALEFAC 11 1
  $===============================================================================
  *END
  $===============================================================================

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LS DYNA Simulation where both impactor and target are ALE [HELP REQUEST]

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