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<p>Hello, I couldn't find any keywords in the Moving shock wave diffraction example in lsdyna examples. Could you provide the related keyword file? If you could, I would be very grateful.</p>
<p>Dear Ansys learning community,</p><p>I am currently working on a project for which I have to design (and validate) a hostile vehicle barrier. In order to validate my designs numerically I want to use LS dyna to simulate a vehicle impact to said barrier. The main reason for me to use LS-dyna is because the European agency has generic vehicle models I can use which have been independently verified. These models are supplied as K files and have an element count of approximatly 150k nodes. However, as I was looking into the possibilities of Ansys LS-dyna (student license) I noticed the maximum problem size consists of 128k nodes/elements.</p><p>My question is thus about how this limit is set. Is this problem limit only for running a simulation or ís it also applied in the pre/post environment? If this limit is only for the solver itself I should (technically) still be able to use LS-dyna pre/post in combination with OpenRadios (opensource K-file solver). Can I use LS dyna pre/post if the problem size exceeds 128k elements or will it cut me off while setting up?</p><p>I look forward to your responses.</p><p> </p>
<p>Dear community, <br><br>I would like to know how we could validate a simple one-element test and a tensile test. I have now generated everything, but I am a bit confused, as my stress-strain curve are all the same with the 3 Rolling direction (0, 45 and 90), the difference is small at a scale of 0.1-0.01. THe material model im using is the MAT133 Barlat Yield 2000-2d. <br>In case you have any idea please let me know. <br><br>Best, </p>
<p>Hello, could you share some examples related to *ALE MESH INTERFACE and *INITIAL LAG MAPPING in the ale update? I keep encountering errors when trying to reproduce them. Or could you point out any precautions I should take? I would be very happy if you could reply. Thank you.</p>
<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>
shalva.esakia@mailbox.tu-dresden.de
October 31, 2025
<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>Hello, I couldn't find any keywords in the Moving shock wave diffraction example in lsdyna examples. Could you provide the related keyword file? If you could, I would be very grateful.</p>
<p>Dear Ansys learning community,</p><p>I am currently working on a project for which I have to design (and validate) a hostile vehicle barrier. In order to validate my designs numerically I want to use LS dyna to simulate a vehicle impact to said barrier. The main reason for me to use LS-dyna is because the European agency has generic vehicle models I can use which have been independently verified. These models are supplied as K files and have an element count of approximatly 150k nodes. However, as I was looking into the possibilities of Ansys LS-dyna (student license) I noticed the maximum problem size consists of 128k nodes/elements.</p><p>My question is thus about how this limit is set. Is this problem limit only for running a simulation or ís it also applied in the pre/post environment? If this limit is only for the solver itself I should (technically) still be able to use LS-dyna pre/post in combination with OpenRadios (opensource K-file solver). Can I use LS dyna pre/post if the problem size exceeds 128k elements or will it cut me off while setting up?</p><p>I look forward to your responses.</p><p> </p>
<p>Dear community, <br><br>I would like to know how we could validate a simple one-element test and a tensile test. I have now generated everything, but I am a bit confused, as my stress-strain curve are all the same with the 3 Rolling direction (0, 45 and 90), the difference is small at a scale of 0.1-0.01. THe material model im using is the MAT133 Barlat Yield 2000-2d. <br>In case you have any idea please let me know. <br><br>Best, </p>
<p>Hello, could you share some examples related to *ALE MESH INTERFACE and *INITIAL LAG MAPPING in the ale update? I keep encountering errors when trying to reproduce them. Or could you point out any precautions I should take? I would be very happy if you could reply. Thank you.</p>
<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>
shalva.esakia@mailbox.tu-dresden.de
October 31, 2025
<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>
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