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Hi! I'm having some trouble downloading LS-PrePost.Every time I try to connect to the FTP server, I get the following error: Access Denied You don't have permission to access "http://ftp.lstc.com/anonymous/outgoing/lsprepost/" on this server.

Hello Team, I have been testing LS-DYNA license features at the request of a customer. I obtained a license file from the Ansys Licensing Portal in March of this year. As far as I know, the standard Ansys LS-DYNA license includes the features "advanced_meshing" and "dyna". For parallel processing, an Ansys LS-DYNA HPC license with the "dysmp" feature is required. Therefore, when running an LS-DYNA model with a single core in Workbench or LS-Run, only one "dyna" feature is used. When running with multiple cores, one "dyna" feature and multiple "dysmp" features are used. However, when I run a model using the license that was issued in March, I see a new feature called "dyna_solver_core" being consumed up to the number of available features. Once the number of requested cores exceeds the available "dyna_solver_core" features, the job then consumes one "dyna" and multiple "dysmp" instead of "dyna_solver_core". I searched for "dyna_solver_core" in the attached Product to Feature Map.pdf (the latest version available in the Download Center), but I could not find any reference to this feature. It appears to be similar to the licensing model used with legacy LSTC LS-DYNA licenses. Has this feature been incorporated into the current Ansys licensing scheme? If anyone is familiar with this feature and can provide additional information, I would greatly appreciate your insights

Hi there, since a few days I am not able to download LS-PrePost from public FTP server (under https://lsdyna.ansys.com/ls-prepost-2/ -> "Download the latest LS-PrePost version here." There is an error: Access Denied You don't have permission to access "http://ftp.lstc.com/anonymous/outgoing/lsprepost/" on this server. Reference #18.b241c717.1786521185.188366ca https://errors.edgesuite.net/18.b241c717.1786521185.188366ca   Access have been tried to be established from TU Dresden, Germany.    

Hello, I want to apply a displacement to two nodes. I checked the Prescribed Motion Node under the Boundary section, but I can only select one node in that card, and I cannot select a node set as well. It is important for my test to apply the displacement directly to the two nodes rather than creating a rigid part and prescribing the displacement to the rigid part.So, I wanted to ask if there is another ways to do this. Also, if Prescribed Motion Node is the only possible way to apply the displacement to two nodes, would it be okay to create one card for each node(two cards in total for loading)? If so, would the prescribed motions start applying at the same time? Thank you for your help.

I am a final-year Mechanical Engineering student currently working on an academic project involving the replication of a published research paper titled "Optimization of Bi-Hexagonal Crash Box Design Using Metal 3D Printing Technology for Enhanced Crashworthiness." (https://doi.org/10.1016/j.nxmate.2026.101841) For our validation study, we replicated the M2 crash box model from the research article using ANSYS Workbench 2026 R1 student version (Explicit Dynamics). We carefully followed the geometry, material properties, boundary conditions, meshing strategy, and loading conditions described in the paper. However, after completing the simulation, we observed that our crashworthiness results differ significantly from those reported in the paper. The values of: Energy Absorption (EA) Specific Energy Absorption (SEA) Crush Force Efficiency (CFE) Peak Crushing Force (PCF) show approximately 40% deviation from the published results. We have repeatedly reviewed our model, including the material assignment, contact definitions, mesh quality, boundary conditions, and analysis settings, but we have not been able to identify the reason for such a large difference. Since this project is part of our academic research, we would greatly appreciate your guidance. We would be grateful if you could review our simulation setup or suggest possible reasons that could lead to this level of deviation. Any recommendations regarding solver settings, contact formulations, element types, material modelling, or other simulation parameters would be extremely valuable.

Hello, I created a very simple LS-DYNA implicit model to test simple restart with cohesive elements. The model runs normally in a continuous implicit analysis. However, when I perform a simple restart using a d3dump file, the analysis fails in the first implicit step after the restart. I tested both:   ELFORM = 19 ELFORM = -19   and the same problem occurs with both cohesive element formulations. I have attached the minimal .k test model, as well as the corresponding messag files from the continuous analysis and the restart analysis. Is this a known limitation or bug related to cohesive solid elements in implicit simple restart? If simple restart is required for an implicit analysis, is there another cohesive element formulation that is recommended? Thank you.K file:$# LS-DYNA Keyword file created by LS-PrePost(R) 2025 R1 (v4.12.9) - 16Oct2025$# Created on Jul-1-2026 (16:49:32)*KEYWORD   *CONTROL_ACCURACY$#     osu       inn    pidosu      iacc     exacc    srtflg         1         4         0         1       2.0         0*CONTROL_BULK_VISCOSITY$#      q1        q2      type     btype    tstype       0.0       0.0         1         0         0*CONTROL_ENERGY$#    hgen      rwen    slnten     rylen     irgen     maten     drlen     disen         2         2         2         2         2         1         1         1*CONTROL_HOURGLASS$#     ihq        qh         6      0.01*CONTROL_IMPLICIT_AUTO$#   iauto    iteopt    itewin     dtmin     dtmax     dtexp     kfail    kcycle         1        11         51.00000E-7     0.001       0.0         0         0*CONTROL_IMPLICIT_DYNAMICS$#   imass     gamma      beta    tdybir    tdydth    tdybur     irate     alpha         0       0.5      0.25       0.01.00000E281.00000E28         0       0.0*CONTROL_IMPLICIT_GENERAL$#  imflag       dt0    imform      nsbs       igs     cnstn      form    zero_v         1     0.001         2         1         0         0         0         0*CONTROL_IMPLICIT_SOLUTION$   NSOLVR    ILIMIT    MAXREF     DCTOL     ECTOL     RCTOL     LSTOL$#  nsolvr    ilimit    maxref     dctol     ectol     rctol     lstol    abstol        12         1        301.0000E-101.0000E-101.00000E-5       0.9       0.0$    DNORM    DIVERG     ISTIF   NLPRINT    NLNORM$#   dnorm    diverg     istif   nlprint    nlnorm   d3itctl     cpchk        -1         1         1         3         2         0         0$    DMTOL     EMTOL     RMTOL               NTTOL     NRTOL     RTTOL     RRTOL$#   dmtol     emtol     rmtol         -     nttol     nrtol     rttol     rrtol1.0000E-101.0000E-101.00000E-4                 0.0       0.0       0.0       0.0$   ARCCTL    ARCDIR    ARCLEN    ARCMTH    ARCDMP$#  arcctl    arcdir    arclen    arcmth    arcdmp    arcpsi    arcalf    arctim         0         0       0.0         1         2       0.0       0.0       0.0$#   lsmtd     lsdir      irad      srad      awgt      sred    kssize         6         2       0.0       0.0       0.0       0.0        10*CONTROL_IMPLICIT_SOLVER$#  lsolvr    lprint     negev     order      drcm    drcprm   autospc   autotol         7         1         2         0         4       0.0         1       0.0$#  lcpack    mtxdmp    iparm1    rparm1    rparm2         -    rparm4    rparm5         2         0       5001.00000E-9     0.001               240.0       0.0$#  emxdmp    rdcmem    absmem   isingle   iblropt         -      ispd    memlvl         0      0.95       0.0         0         0                   0       0.0*CONTROL_TERMINATION$#  endtim    endcyc     dtmin    endeng    endmas     nosol 3.260E+01         0       0.0       0.0       0.0         0*CONTROL_TIMESTEP$#  dtinit    tssfac      isdo    tslimt     dt2ms      lctm     erode     ms1st       0.0      1e-5         0       0.0       0.0         0         0         0$#  dt2msf   dt2mslc     imscl    unused    unused     rmscl     emscl      ihdo       0.0         0         0                           0.0       0.0         0*DATABASE_EXTENT_BINARY$#   neiph     neips    maxint    strflg    sigflg    epsflg    rltflg    engflg        80         3         3         1         1         1         1         1$#  cmpflg    ieverp    beamip     dcomp      shge     stssz    n3thdt   ialemat         0         0         4         1         1         1         2         0$# nintsld   pkp_sen      sclp     hydro     msscl     therm    intout    nodout         8         0       1.0         0         0         0STRESS    STRESS$#    dtdt    resplt               0         0         3*DATABASE_BNDOUT$#      dt    binary      lcur     ioopt   option1   option2   option3   option4      0.01         2         0         1         0         0         0         0*DATABASE_GLSTAT$#      dt    binary      lcur     ioopt      0.01         2         0         1*DATABASE_MATSUM$#      dt    binary      lcur     ioopt     0.001         2         0         1*DATABASE_SPCFORC$#      dt    binary      lcur     ioopt      0.01         2         0         1*DATABASE_BINARY_D3PLOT$#      dt      lcdt      beam     npltc    psetid     0.001         0         0         0         0$#   ioopt      rate    cutoff    window      type      pset         0       0.0       0.0       0.0         0         0*DATABASE_BINARY_D3DUMP$#      dt      lcdt      beam     npltc    psetid         1         0         0         0         0*LOAD_SEGMENT     10001     0.5E6         0        13        14        16        15*DEFINE_CURVE$#    lcid      sidr       sfa       sfo      offa      offo    dattyp     lcint     10001         0       1.0       1.0       0.0       0.0         0         0$#                a1                  o1  0.000000000000E+00  0.000000000000E+00  5.000000000000E-01  1.000000000000E+00  6.000000000000E-01  1.000000000000E+00  3.260000000000E+01  1.000000000000E+00*BOUNDARY_PRESCRIBED_MOTION_SET$#    nsid       dof       vad      lcid        sf       vid     death     birth         2         1         2     10000       1.0         0       0.0       0.0*DEFINE_CURVE$#    lcid      sidr       sfa       sfo      offa      offo    dattyp     lcint     10000         0       1.0       1.0       0.0       0.0         0         0$#                a1                  o1  0.000000000000E+00  0.000000000000E+00  6.000000000000E-01  0.000000000000E+00  1.133333333333E+00  8.000000000000E-03  2.200000000000E+00 -8.000000000000E-03  2.733333333333E+00  0.000000000000E+00  3.266666666667E+00  8.000000000000E-03  4.333333333333E+00 -8.000000000000E-03  4.866666666667E+00  0.000000000000E+00  5.400000000000E+00  8.000000000000E-03  6.466666666667E+00 -8.000000000000E-03  7.000000000000E+00  0.000000000000E+00  7.533333333333E+00  8.000000000000E-03  8.600000000000E+00 -8.000000000000E-03  9.133333333333E+00  0.000000000000E+00  9.666666666667E+00  8.000000000000E-03  1.073333333333E+01 -8.000000000000E-03  1.126666666667E+01  0.000000000000E+00  1.180000000000E+01  8.000000000000E-03  1.286666666667E+01 -8.000000000000E-03  1.340000000000E+01  0.000000000000E+00  1.393333333333E+01  8.000000000000E-03  1.500000000000E+01 -8.000000000000E-03  1.553333333333E+01  0.000000000000E+00  1.606666666667E+01  8.000000000000E-03  1.713333333333E+01 -8.000000000000E-03  1.766666666667E+01  0.000000000000E+00  1.820000000000E+01  8.000000000000E-03  1.926666666667E+01 -8.000000000000E-03  1.980000000000E+01  0.000000000000E+00  2.033333333333E+01  8.000000000000E-03  2.140000000000E+01 -8.000000000000E-03  2.193333333333E+01  0.000000000000E+00  2.246666666667E+01  8.000000000000E-03  2.353333333333E+01 -8.000000000000E-03  2.406666666667E+01  0.000000000000E+00  2.460000000000E+01  8.000000000000E-03  2.566666666667E+01 -8.000000000000E-03  2.620000000000E+01  0.000000000000E+00  2.673333333333E+01  8.000000000000E-03  2.780000000000E+01 -8.000000000000E-03  2.833333333333E+01  0.000000000000E+00  2.886666666667E+01  8.000000000000E-03  2.993333333333E+01 -8.000000000000E-03  3.046666666667E+01  0.000000000000E+00  3.100000000000E+01  8.000000000000E-03  3.206666666667E+01 -8.000000000000E-03  3.260000000000E+01  0.000000000000E+00*SET_NODE_LIST$#     sid       da1       da2       da3       da4    solver       its         -         2       0.0       0.0       0.0       0.0MECH               1          $#    nid1      nid2      nid3      nid4      nid5      nid6      nid7      nid8         9        10        11        12        13        14        15        16*BOUNDARY_SPC_SET$#    nsid       cid      dofx      dofy      dofz     dofrx     dofry     dofrz         2         0         0         1         0*BOUNDARY_SPC_SET$#    nsid       cid      dofx      dofy      dofz     dofrx     dofry     dofrz         1         0         1         1         1*SET_NODE_LIST_TITLENODESET(SPC) 1$#     sid       da1       da2       da3       da4    solver       its         -         1       0.0       0.0       0.0       0.0MECH               1          $#    nid1      nid2      nid3      nid4      nid5      nid6      nid7      nid8         1         2         3         4         5         6         7         8*MAT_ELASTIC_TITLEROCK_OUTTER$#     mid        ro         e        pr        da        db  not used         1      2700 1.700E+10      0.23         0         0         0*MAT_COHESIVE_ELASTIC_TITLECOHESIVE         2 1.000E-06         1         0 2.400E+09 3.000E+10 1.000E+20 1.000E+20*MAT_ELASTIC_TITLEROCK_OUTTER$#     mid        ro         e        pr        da        db  not used         3      2700 1.700E+10      0.23         0         0         0*SECTION_SOLID$#    secid    elform         1         2*SECTION_SOLID$#    secid    elform         2        19*PART$#                                                                         titleboxsolid$#     pid     secid       mid     eosid      hgid      grav    adpopt      tmid         1         1         1         0         0         0         0         0*PART$#                                                                         titleboxsolid$#     pid     secid       mid     eosid      hgid      grav    adpopt      tmid         2         2         2         0         0         0         0         0*PART$#                                                                         titleboxsolid$#     pid     secid       mid     eosid      hgid      grav    adpopt      tmid         3         1         3         0         0         0         0         0*NODE$#   nid               x               y               z      tc      rc       1             0.0             0.0             0.0       0       0       2            0.15             0.0             0.0       0       0       3             0.0            0.15             0.0       0       0       4            0.15            0.15             0.0       0       0       5             0.0             0.0           0.075       0       0       6            0.15             0.0           0.075       0       0       7             0.0            0.15           0.075       0       0       8            0.15            0.15           0.075       0       0       9             0.0             0.0           0.075       0       0      10            0.15             0.0           0.075       0       0      11             0.0            0.15           0.075       0       0      12            0.15            0.15           0.075       0       0      13             0.0             0.0            0.15       0       0      14            0.15             0.0            0.15       0       0      15             0.0            0.15            0.15       0       0      16            0.15            0.15            0.15       0       0*ELEMENT_SOLID$#   eid     pid      n1      n2      n3      n4      n5      n6      n7      n8       1       1       1       2       4       3       5       6       8       7       2       2       5       6       8       7       9      10      12      11       3       3       9      10      12      11      13      14      16      15*ENDmessag01 file  after simple restart: read d3dump1337 file BEGIN implicit statics step 1337 t=1.3370E+00 Linear step computedInitial translational energy = NaNInitial total energy         = NaNInitial residual norm        = NaNTranslational nodes norm     = NaN

Hi everyone, I am trying to set up a DUALCESE model to simulate a gas jet but I am getting a hierchy error. From what I have learned I need to define all my DUALCESE keywords under the DUALCESE_MODEL hierchy but the DUALCESE_MODEL keyword seems to dissappear from the keyword deck after I save the project.  Can someone please guide me on ho to set-up a correct hierchy for the problem or if there are any documents availabe, would really appreaciate it. Thanks in advance.  

<p class="PDq2pG_selectionAnchorContainer" data-start="87" data-end="93"><span style="font-size: 12pt;">Hello,</span></p><p class="" data-start="95" data-end="245"><span style="font-size: 12pt;">I am using LS-DYNA 2025 R2 on Windows to obtain the unloaded configuration of a pressurised hyperelastic model using *CONTROL_REFERENCE_CONFIGURATION.</span></p><p data-start="247" data-end="293"><span style="font-size: 12pt;">The analysis is launched with the CASE option, as required:</span></p><p data-start="295" data-end="374"><span style="font-size: 12pt;">mpiexec -np %NCPU% -aa -a "%SOLVER%" CASE i=run_zero_p_config.k memory=%MEMORY%</span></p><p data-start="376" data-end="520"><span style="font-size: 12pt;">The target.k file contains only the target nodal coordinates. The material is an Ogden hyperelastic model, and the forward analysis is implicit.</span></p><p data-start="522" data-end="720"><span style="font-size: 12pt;">LS-DYNA generates iter2.inp and iter1.guess, but it does not generate iter1.algo. When iteration 2 starts, LS-DYNA crashes in REPNOD, apparently while attempting to read the missing iter1.algo file:</span></p><p data-start="722" data-end="780"><span style="font-size: 12pt;">forrtl: severe (157): Program Exception - access violation</span></p><p data-start="782" data-end="909"><span style="font-size: 12pt;">lsdyna_mpp_dp_msm REPNOD 37088 dynkab.F</span><br><span style="font-size: 12pt;">lsdyna_mpp_dp_msm KEYWRD 12115 dynkaa.F</span><br><span style="font-size: 12pt;">lsdyna_mpp_dp_msm LSINPUT 1482 dynm.F</span></p><p data-start="911" data-end="1027"><span style="font-size: 12pt;">I have tested both the MPP and SMP executables, and the same issue occurs, so it does not appear to be MPI-specific.</span></p><p data-start="1029" data-end="1285"><span style="font-size: 12pt;">Could anyone please advise whether iter1.algo should always be generated automatically after iteration 1? Is this a known issue with *CONTROL_REFERENCE_CONFIGURATION in the 2025 R2 Windows build?</span></p><p data-start="1287" data-end="1393"><span style="font-size: 12pt;">Any guidance would be greatly appreciated. I understand the issue with this keyword has been brought up some time ago - may I inquire about any fix since then, or any successful examples to share? I can provide the input and iteration output files, in any feasible way, if required.</span></p><p data-start="1395" data-end="1408"><span style="font-size: 12pt;">Thank you.</span></p>

I am using LS-Dyna R11.2.2. I am performing an explicit simulation and then perform the implicit springback step.  I have successfully used the 2-step approach, in which I call the *INTERFACE_SPRINGBACK_LSDYNA in the first simulation, and then include the generated dynain file in the second simulation. This approach works.  However, I have tried to combine both approaches using *INTERFACE_SPRINGBACK_SEAMLESS, and while the simulation runs, it will not output the ASCII dynain or lsda binary files. I have tried to include both *INTERFACE_SPRINGBACK_SEAMLESS and *INTERFACE_SPRINGBACK_LSDYNA in the same keyword, but then the implicit simulation does not run at all, though it outputs some dynain file.  Is there any conflict between using *INTERFACE_SPRINGBACK_SEAMLESS and generating the corresponding dynain file automatically?

Hello, I am investigating an output-mapping and energy-conservation issue in an academic civil/mining solver-verification unit test. This is not a weapon or defence model. Environment: Ansys LS-DYNA Student, Windows x64 SMP double precision R16.1-180-gd50332dbe5, one thread Units: mm-ms-g-N-MPa 2D axisymmetric S-ALE, 12,423 cells 808 cells initially filled with EMULSION *MAT_HIGH_EXPLOSIVE_BURN (MAT_008, BETA=0) with *EOS_JWL NEIPH=4, D3SALE=0, DMPMSH=1 Termination time: 0.100 ms I compared two input decks that are identical except for the lighting time LT in *INITIAL_DETONATION: v3: LT=0.0 msNormal termination, but the maximum absolute total-energy drift calculated from all original GLSTAT states is 15.995852%. E2: LT=0.200 ms, after the 0.100 ms termination timeNormal termination, and the maximum absolute total-energy drift is only 0.00049064%. No interpolation, state deletion, filling, smoothing or renormalization was used. However, I cannot yet prove from the original output that burn fraction F remained zero in all 808 explosive cells in E2. The binout contains only nine tracers, and the R16.1 manuals do not identify the exact full-field burn-fraction mapping for 2D axisymmetric S-ALE. Could an LS-DYNA specialist please clarify: With D3SALE=0, where exactly is the per-S-ALE-cell MAT_008/JWL burn fraction F stored in d3plot? Please identify the documented array/record location and the LS-PrePost Fcomp or Misc component. With D3SALE=1, what is the corresponding LSDA path and array name in d3sale? Is NEIPH=4 sufficient for full-field burn-fraction output for MAT_008 + EOS_JWL in 2D axisymmetric S-ALE? Does HISNOUT=3 provide valid labels for this field? Are these output fields identical between the R16.1 Student and commercial executables? Is the approximately 16% energy loss for LT=0, compared with approximately 0.00049% for LT=0.200 ms, a known R16.1 limitation, defect or energy-accounting behavior? Is there a recommended patch level, diagnostic output or control setting? I am not claiming that the A/B comparison uniquely proves that burn, JWL or advection is the cause. I first need the officially supported full-field burn-fraction mapping. Thank you.