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<p>Dear all,</p><p>I use the LS-DYNA ICFD module to perform CFD simulations applied to intracranial arteries.</p><p>I am currently conducting a mesh convergence study.</p><p>I perform surface meshing using Tetgen embedded in VMTK.</p><p>I then let LS-DYNA perform volume meshing based on the surface mesh.</p><p>For the implementation of boundary layers, Tetgen uses coefficients and ratios (sublayer ratio, boundary layer thickness factor) for the meshing of prismatic elements.</p><p>In LS-DYNA, the *MESH_BL card offers automatic boundary layer meshing with NELTH+1 layers when the default settings are selected.</p><p>Two questions:</p><p>1) I would like to know if it is possible to set a factor to calculate the boundary layer thickness rather than having to set an exact thickness in mm, cm or m via BLTH, BLFE and BLST.</p><p>2) What coefficients are used by *MESH_BL in the automatic inflation of boundary layers?</p><p>Thank you,</p><p>Guillaume</p>

<p>Hello, I am simulating the bullet impact on glass and laminated glass with PVB interlayer. The problem that I found is that when the bullet hits the target it prematurely deletes that mesh elements that are not even touched yet. It might be correct but considering the fact that I was not able to find the ballistic limit of the monolithic glass even at 50mm thickness against simple cone bullet with 400m/s velocity is concerning to me. The material model used for the glass is JH2 for tempered glass. I was wondering if in the analysis settings of Explicit Dynamics tool, it is correct to turn off erosion on material failure and only leave the erosion on geometric strain. This actually does not trigger the presumed premature deletion of the elements but the model now is very sensitive to the strain limit, giving me drastically different residual velocities for the bullet on different limits. Is it correct to pursue the callibration of the geometric strain limit value or is it waste of time? I feel like as the erosion on material failure is turned off the JH2 material model becomes undermined in calculation and the software is only focusing on strain limits. Is this correct? What other thing can be a problem that triggers this inconsistancy in my initial simulation when the material failure erosion is turned on? <br>Thank you!</p>

<p>I am analysing a composite plate subjected to pressure on the upper face and constrained at the short sides.<br>I would like to obtain the von Mises sigma results for the isotropic material at the centre of the layout, but I am unable to do so. I have set the correct number of integration point parameters and I obtain the stress for the other layers, but not for that one. </p>

<p><p>Hello everyone. I wanted to split a task into cores.<br>I tried to do a very basic division. I added the CONTROL_DECOMPOSITION_AUTOMATIC map. I also specified the number of cores in the launcher.</p><p></p><p><br>BUT when I launch it, I get the following errors:</p><p></p><p>Intel MPI and Microsoft MPI are not working.</p><p>Why isn't this working?<br>Thanks.</p></p>

<p>lsprepost导入sat模型后划分网格卡住 </p>

<p><span style="font-size: 12pt;">We want to be sure that the fasteners and springs are using a correct CID and the shear and axial loads are well transmited.</span><br><br><span style="font-size: 12pt;">For fasteners, we are currenlty using ELEMENT_BEAM without a third node, SECTION_BEAM elform 9 and SCOOR 2 and MAT SPOTWELD.</span><br><br><span style="font-size: 12pt;">For the springs, as we need stiffness in all three translations, we are using ELEMENT_BEAM without a third node, SECTION_BEAM elform 6, no CID and SCOOR 2,  MAT_LINEAR_ELASTIC_DISCRETE_BEAM with the respective values on TKR, TKS and TKT. </span></p><p><span style="font-size: 12pt;">If you need any more data, please share it. </span></p>

<p>Hi all.<br>I'm counting on the impact.<br>I created a mesh in Ls_dyna's WORKBENK and imported it into the prepost.<br>I created a mesh of Patch Independent tetrahedrons.</p><p></p><p>Now if my bodies have SECTION ELFORM=1, I get an infinite division of timesteps:</p><p></p><p>Is it because of the mesh?</p><p>If I set ELFORM=10, it starts working on some models. And on some, everything also goes into endless division.</p><p>Thanks.</p>

<p>Hello,</p><p>I am getting following error while runing LS DYNA DOUBLE PRECISION MPP for fluid structure interaction simulation using CESE and structural solver.</p><p></p><p>Regards,<br>Atish</p>

<p>Hello everyone. I'm solving an impact problem. A steel cylinder impacts a CNG plate.<br>When I calculate with MASSCALE D2TMS, everything works.<br>If I remove the mass scale, I get an error:</p><p><span style="color: #e03e2d;">     871 t 9.9996E-02 dt 1.15E-04 write d3plot file            10/27/25 17:51:10</span><br><span style="color: #e03e2d;">    1741 t 1.9999E-01 dt 1.15E-04 write d3plot file            10/27/25 17:52:35</span><br><span style="color: #e03e2d;">    2611 t 2.9999E-01 dt 1.15E-04 write d3plot file            10/27/25 17:54:15</span><br><span style="color: #e03e2d;">    3705 t 3.9995E-01 dt 8.81E-05 write d3plot file            10/27/25 17:56:47</span><br><span style="color: #e03e2d;">    4887 t 4.9998E-01 dt 6.33E-05 write d3plot file            10/27/25 17:59:39</span><br><span style="color: #e03e2d;">    5000 t 5.0722E-01 dt 6.26E-05 flush i/o buffers            10/27/25 17:59:56</span><br><span style="color: #e03e2d;">    7999 t 5.9999E-01 dt 1.69E-05 write d3plot file            10/27/25 18:07:35</span><br><span style="color: #e03e2d;">   10000 t 6.1699E-01 dt 8.01E-06 flush i/o buffers            10/27/25 18:12:49</span><br><span style="color: #e03e2d;">forrtl: severe (157): Program Exception - access violation</span><br><span style="color: #e03e2d;">Image              PC                Routine            Line        Source</span><br><span style="color: #e03e2d;">lsdyna_dp.exe      00007FF7DCBB0408  BKSRT4A                 15470  fem3d_a.F</span><br><span style="color: #e03e2d;">lsdyna_dp.exe      00007FF7E2CA3198  ASLAV0R                 28402  dynpc.F</span><br><span style="color: #e03e2d;">lsdyna_dp.exe      00007FF7DFA3C15A  CONTACT                  2747  dyn33.F</span><br><span style="color: #e03e2d;">lsdyna_dp.exe      00007FF7DCC0E4E0  FEM3D_CONTACT           39418  fem3d_a.F</span><br><span style="color: #e03e2d;">lsdyna_dp.exe      00007FF7DCB4F840  FEM3D                   12147  fem3d.F</span><br><span style="color: #e03e2d;">lsdyna_dp.exe      00007FF7DCB42858  SOLTN                     441  fem3d.F</span><br><span style="color: #e03e2d;">lsdyna_dp.exe      00007FF7DCC7DC38  OVERLY                    277  dyn0.F</span><br><span style="color: #e03e2d;">lsdyna_dp.exe      00007FF7DB8047BF  LSDYNA1                   965  dynm.F</span><br><span style="color: #e03e2d;">lsdyna_dp.exe      00007FF7DB804129  MAIN__                   2060  dynm.F</span><br><span style="color: #e03e2d;">lsdyna_dp.exe      00007FF7E98BD3E2  Unknown               Unknown  Unknown</span><br><span style="color: #e03e2d;">lsdyna_dp.exe      00007FF7EA1D0358  Unknown               Unknown  Unknown</span><br><span style="color: #e03e2d;">KERNEL32.DLL       00007FF8EED8E8D7  Unknown               Unknown  Unknown</span><br><span style="color: #e03e2d;">ntdll.dll          00007FF8EF6AC53C  Unknown               Unknown  Unknown</span></p><p>Why?<br>Thanks.</p>

<p>Hello everyone. I'm simulating an impact.<br>One element hits another, and it hits the SPG particles—the concrete. But the body passes through the particles. It worked before. Why did it break? I'm attaching a screenshot of the contact, as well as an image of how the particles should fly apart.</p><p></p><p></p><p></p><p> </p>