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<p>How should I set LS-Prepost to achieve the pressure cloud map style shown in the figure</p>

<p>I'm installing LSDYNAR version 5.1.1, but the machine code fails to generate during the installation process. What could be causing this?</p>

<p>I was trying to figure out LS-DYNA would be available for piping stress analysis using Elbow Beam.</p><p>So, I made two models for the comparison between regular beam (ELFORM = 1) and elbow beam (ELFORM = 14) under *LOAD_BODY_Y with structural mass only.</p><p>I guess the deformed configuration of the regular beam seems reasonable while one of the elbow beam unrealistic.</p><p>I know elbow element is still in beta but I think I have to use elbow element to incorporate the pressure stiffening effect into the analysis.</p><p>Is it a bad idea to use LS-DYNA for piping stress analysis for now?</p><p>By the way, I have found the NSM field in *SECTION_BEAM for elbow element would not work properly. I got a overestimated physical mass in "messag" file.</p><p></p>

<p><p>I tested LSPP version 4.10 to 4.13 in 3 different computers, there are same problems. </p>

<p>Workbench 2025R2 start support Mat187L. In workbench it only provide 2 options for "the strain rate caculation"? EQ1 is best but missed. Can Ansys correct it in next version? </p>

<p>PLEASE REQUESTED SIR COMPELTE THE MY INTERNSHIP </p>

<p>Is there any reason that control_adaptive does not work with mat_add_inelasticity coupled with a hyperelastic material model?</p>

<p>How can I better understand below statement from the documentation about control_adaptive and hyperelastic materials?   Why is adaptive remeshing having problems with large deformation problems or with hyperelastic materail model?   I suspect it has to do with how strain energy potentials are implemented but I honestly have no idea and I would like to develop some basic understanding of why this is an issue and to what degree it is an issue?<br><br>Has anyone in Ansys done any studies that can be shared with me?</p><p></p>

<div>Link to my umat49v and Keyword files<br><br>Hello,</div><div> </div><div>I'm experiencing an issue with coupling a user-defined material (UMAT49V) to an equation of state in LS-DYNA R16.1. The EOS pressure array pc(i) accessed via common/eosdloc/ remains zero throughout the simulation, even though the configuration appears correct.</div><div> </div><div>Environment:</div><div>- LS-DYNA Version: R16.1-182-g5848067bc5 (MPP, Windows 10, Intel Fortran 19.0)</div><div>- Material: *MAT_USER_DEFINED_MATERIAL_MODELS (MT=49)</div><div>- EOS: *EOS_GRUNEISEN (EOSID=1)</div><div> </div><div>Configuration:</div><div>My material card is set up with:</div><div>- IEOS = 1 (EOS coupling enabled)</div><div>- NHV = 12 (reserved 4 slots for EOS as per manual)</div><div>- PART card references both MID=1 (UMAT) and EOSID=1 (EOS)</div><div> </div><div>In my UMAT49V subroutine, I access the pressure via:</div><div>text</div><div>  common/eosdloc/pc(nlq)</div><div>  ...</div><div>  p_eos = pc(i)</div><div>text</div><div> </div><div>Observed Behavior:</div><div>- Debug prints show pc(i) = 0.0 for all cycles</div><div>- The UMAT is being called (deviatoric stresses compute correctly)</div><div>- Time stepping is working (4347 cycles completed)</div><div>- Elements are deforming (strain increments are non-zero)</div><div> </div><div>What Works:</div><div>- MAT_010 (*MAT_ELASTIC_PLASTIC_HYDRO) with the SAME *EOS_GRUNEISEN card works correctly and produces non-zero pressure</div><div>- This confirms the EOS card itself is valid</div><div> </div><div>Question:</div><div>Is the common/eosdloc/pc() mechanism supported for *MAT_USER_DEFINED_MATERIAL_MODELS in R16.1? The manual (Appendix A, section on user materials with EOS) states that I should:</div><div>1. Set IEOS=1</div><div>2. Reserve first 4 history variables for EOS</div><div>3. Access pressure via pc(i)</div><div> </div><div>I've done all three, but pc(i) never gets populated. Is there a compilation flag, additional include file, or different approach needed for user materials to access EOS pressure in R16?</div><div> </div><div>Workaround Consideration:</div><div>Would implementing the EOS in dyn21ueos.f (using ueos41) instead of relying on external *EOS_GRUNEISEN cards be more reliable for user material coupling?</div><div> </div><div>Any guidance would be greatly appreciated. I can provide the full keyword file and UMAT code if needed for troubleshooting.</div><div> </div><div>Thank you,</div><div>Amrith<br><br><br></div>

<p>Hi everyone,</p><p>I’m working on a 2D axisymmetric hypervelocity impact simulation in LS-DYNA and am trying to apply non-reflecting boundary conditions to the outer edges of the target domain (bottom and right boundaries).</p><p>When I select all nodes along those boundaries and assign:</p>*BOUNDARY_NON_REFLECTING_2D <p>I receive the following error:</p>*** Error 21385 (STR+1385) The node set of *BOUNDARY_NON_REFLECTING_2D 1 has 2 non-consecutive nodes: 94606 94884 <p>However, if I apply the boundary card to only a single node on each boundary, the error disappears — but that clearly isn’t physically correct for wave absorption.</p><p>My understanding is that node numbering along the boundary must be sequential for NRBC to work correctly, but I’m not sure of the best practice to enforce this in a 2D axisymmetric mesh (e.g., whether to define separate segments, sort nodes, or restructure the mesh).</p><p>Could anyone please advise on the correct way to define non-reflecting boundaries for a 2D axisymmetric ALE/Lagrangian model? I’ve attached my keyword files at the link provided for reference.</p><p>Any guidance would be greatly appreciated!</p><p>Thanks,<br>Amrith<br><br>Keyword File</p>