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I am running an implicit analysis on a foam-filled square tube. I am using a single curve for both the loading and unloading. The solver crashes during the unloading phase. Could you please advise on which inputs are incorrect or causing conflict? squaretubefoam.key

Additional controlled test completed: a 2× S‑ALE mesh refinement changed the maximum total-energy loss only from 1.58755% to 1.59180%. Mass conservation, geometry, stable timestep, GLSTAT component closure and material-account closure all pass. The loss is primarily associated with the EMULSION material. Could anyone clarify two R16.1 output semantics questions? Is Ekinlos an additive energy term that should be included in the global conservation balance? Which supported database/output gives per-cell, per-material internal energy, kinetic energy and burn fraction for axisymmetric S‑ALE with *MAT_HIGH_EXPLOSIVE_BURN/JWL? These definitions are needed before further numerical changes can be interpreted.

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.