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Hi everyone, I am setting up an ICFD simulation of gas flow through a porous domain in LS-DYNA. The model currently consists of the  fluid domain and the porous-medium region; I am not yet including structural deformation. During initialization, the simulation terminates with the following error:   *** Error 120003 (ICFD+3) ICFD::ERROR: Invalid BC on SIZE or INTERF surf. PID 1     The simulation does not proceed beyond initialization. I am using an ICFD volume part for the porous medium and have defined the corresponding ICFD material and porous-medium model. I suspect that the issue is related to the boundary condition assigned to the surface with PID 1, but I am unsure what constitutes an invalid BC for a SIZE or INTERF surface in this setup. Could someone please clarify: What does "Invalid BC on SIZE or INTERF surf. PID 1" specifically mean? What boundary conditions are permitted on SIZE and INTERF surfaces? How should the surfaces of a porous ICFD volume be defined when modelling hydrogen flow into/through porous soil? Is there a particular ICFD keyword or surface definition that I should check? Thank you in advance.

Hello all! I'm currently extracting several variables from my model where several bodies contact one another with a near-frictionless penalty-based contact (*CONTACT_AUTOMATIC_SINGLE_SURFACE). I'm trying to compare contact variables to an experimental reference where they report peak pressure, mean pressure, and contact area gathered using Tekscan pressure films. I have some questions that I hope someone else has experience with. If two different parts are in contact, should both parts have the same contact pressure, force, and area readings? I have a force transducer on each of the two contacting parts, and I found that the forces from RCFORC agree pretty much exactly, but the results for pressure and contact area were close (~5 to 20% difference) and not exactly the same. Is this related to the mesh or element density, or could it point to something wrong in my contact setup? If it is just discretization, is there a recommended convention for which side to report or to average both sides? I noticed that I have access to several "pressure" variables in LS-PrePost, so I'm wondering what each variable represents and which could be better suited to my purpose:a) "Pressure" from d3plot, which I guess could be hydrostatic pressureb) "Interface Pressure" from intfor, obtained using a transducerc) "Peak Pressure" from intfor, after setting NPRESU to 3 on *DATABASE_EXTENT_INTFOR I compared these three variables across several simulations and the values were close, but not exactly the same. Is any of these options better to compare against a pressure film? Also, what's the difference between peak pressure and just taking the maximum value of interface pressure at a given state?3. Related to the above, I also need contact area for the same comparison. Would anyone know how LS-PrePost computes the "Contact Area" quantity? Is there a threshold being used to sum elements or does it add all elements with nonzero values?Thanks in advance for any guidance!Best,  Andres  

Hello, I am currently using the Ansys LS-DYNA Student version for my academic research. Until a few days ago, LS-DYNA displayed the following warning when I started an analysis: Student license active, 1 days remaining. The license has now expired, and LS-DYNA terminates with the following messages: [license/error] *** ANSYS LICENSE MANAGER ERROR ***[license/error] Request name dyna does not exist in the licensing pool.Student license expired 2 days ago.*** Error 70022 (OTH+22)Error termination Therefore, I am currently unable to run LS-DYNA analyses. I checked the official Ansys Student download pages to renew the license. However, I could not find a newer LS-DYNA Student version with an updated built-in license. I understand that the LS-DYNA Student license is built into the Student version and that simply replacing a license file is no longer the recommended renewal procedure. Could you please advise me on the following? Is there a newer version of LS-DYNA Student with a valid license that I can download? If not, how can I renew or update the LS-DYNA Student license? Is there another recommended procedure for continuing to use LS-DYNA Student until the next version is released? I have attached a screenshot of the Error 70022 message for reference. Thank you for your assistance.

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.