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<p>Hello everyone.<br>I'm simulating an urban blast calculation in the explicit module, but first I put together a small test problem.<br>I need help with some settings.<br>1. I have three solid bodies: a cylinder, a TNT charge (a sphere), and air (a cube surrounding everything).<br>The TNT charge and air are Eulerian solids, and the cylinder is a Lagrange solid.</p><p><br>The mesh has 70,000 elements.</p><p><br>2. I set the calculation time to 0.001 since the model is small. For a large model, the calculation time is 1-15 ms because it includes a large building.</p><p><br>3. I also adjusted the SPH speed time and the number of cells for my model, and I increased the number of result records to 200 (see images).<br>4. The calculation time is 10 minutes. I also configured the solver to Autodyn.</p><p><br>5. I display the results: Total Deformation (for the body around the charge), Pressure (expression), ALPHAALL (expression).<br>These are the results I see:</p><p></p><p></p><p></p><p>6. Now I want to see how the explosion waves propagate and make a nice animation, like this:</p><p></p><p>How do I do this?<br>Thanks!</p>
<p>Hello all,</p><p>I am trying to use a compiled solver from the usermat version of LS-DYNA. Initially I had some issues compiling the solver with the Makefile, but after adding some lines to the LIBS variable in the Makefile, I was able to compile something. However, when trying to use the file made with the Makefile, with LSrun, I get a license error.</p><p></p><p>I tried some of the suggested solutions from previous posts, such as:</p><p>export ANSYSLMD_LICENSE_FILE=127.0.0.1</p><p>env ANSYSLMD_LICENSE_FILE=1055@127.0.0.1</p><p>In the lsout file, it says "license option:check ansys licenses only" at the top. I am using the usermat version of R13.1 mpp double precision. I also saw an "ansyscl" file was mentioned. If this is needed, where would it be located when downloading the compressed folder? Is it supposed to be inside the compressed folder? I am unable to find file. Also looking in the license tab of LSrun shows licences are active and are waiting to be used.</p><p>Best,</p><p>K</p>
<p>I am running a Hypervelocity Impact simulation of a projectile impacting an assembly built with Constrained nodal rigid bodies and Beam elements to represent the bolts.</p><p>When I run the model without setting a Control_termination endtime (so just initialise the model with a velocity applied to the impactor) it will initalise normally and terminate normally. But when I include the Control_termination endtime keyword and run the model, it will initialise but then all the solid elements which are connected to my CNRB fail on the first timestep.</p><p>Could someone help explain why this might be the case please?</p><p>For context, the model is built from entirely solid meshes (quad and tet for different parts), and the elements which are failing are those connected to a second order solid tetrahedral mesh (the mesh was generated in hypermesh and imported to LS DYNA) - for this part I am using a Solid Section with ELFORM 16 following literature I found online. </p><p> </p><p>Thank you!</p>
<p class="isSelectedEnd">Hi everyone,</p><p class="isSelectedEnd">I am running a windshield impactor test in LS-DYNA using <code dir="ltr">*MAT_ELASTIC glass shell elements with <code dir="ltr">*MAT_ADD_EROSION.</p><p class="isSelectedEnd">The erosion card includes a critical stress, critical strain energy, and critical radius. My understanding is that when a glass element reaches the critical stress, LS-DYNA evaluates the accumulated strain energy within the specified radius around that element. If this accumulated strain energy exceeds the critical energy, the related elements are eroded.</p><p class="isSelectedEnd">For my study, I want to keep the critical energy very high so that erosion does not occur, and I want to post-process the time history of this accumulated strain energy during the windshield impact.</p><p class="isSelectedEnd">However, I cannot find this quantity in the output. I can only see part-level <code dir="ltr">internal_energy from <code dir="ltr">MATSUM, but this is not the local strain energy I need.</p><p class="isSelectedEnd">How can I get this strain energy output in LS-DYNA?</p><p class="isSelectedEnd">Thank you</p><p class="isSelectedEnd">Ali</p>
<p>Hello, I've created a model to calculate the pressure on a hull during a water entry.</p><p>I've used S-ALE method and on my PC it works, I get pressure measures using DATABASE_FSI keyword and then exporting the csv files.</p><p>I have to get a bigger analysis of a complete structure impacting water and I use a MPP.</p><p>I've just tryed to run the same analysis (the one which works on my pc) on the MPP but I can't get the dbfsi file I need.</p><p>The plot I get in post processing are just many plots all with the same values which are not correct, they are all equal to the results of the first sensor I've placed on the bottom of the shell element. The dbfsi doesn't appear in the ASCII files and so I have to select the BINOUT option and import the "results".</p><p>I don't understand what I'm doing wrong, the run files are the same but the results I need don't appear</p><p> </p><p></p>
<p><p>Hello all,</p><p>I been having the same issue as described by Atish Gawale in a previous post: running simulations on a linux graphical interface through lsrun, where running on SMP single precision worked fine, but got a forrtl: severe (174): SIGSEGV, segmentation fault occurred when trying to run on MPP double-precision.</p><p></p><p>Has anyone found a fix/reason for this issue?</p><p>I have tried different versions of LS-Run and solver executables, and I still get the same issue: same error message w/ MPP, but it works w/ SMP.</p><p>My simulation has no contact, it is a cubic lattice undergoing displacement controlled uniaxial compression. </p><p>Best,</p><p>K</p></p>
<p>Greetings!</p><p>I'm attempting to simulate a simple model: a cylindrical specimen under gravity load supported by a rigid plate in <span style="text-decoration: underline;">LS-DYNA SMP double precision</span>. The plate is fixed in all degrees of freedom. The SPG parameters are set as follows: KERNEL=2, ITB=3, MSC=1, PDAMP=-0.001, DX=DY=DZ=1.6. Despite its apparent simplicity, the model exhibits instability after about 0.06 seconds. The specimen begins to move without any reason (no changes made to the model). I've noticed unphysical oscillations in acceleration values - they start to grow to extremely high values (1e06 m/s^2 and more) and I don't know why. I tested different SPG parameters (different KERNEL, ITB, MSC, DX, DY, DZ values) but the issue remain unsolved. Also I tried to include some damping to model (PART_MASS, PART_STIFFNESS, FREQUENCY_RANGE) but nothing helped. The contact between SPG part (specimen) and FEM part (plate) is defined using DEFINE_SPG_TO_SURFACE_COUPLING card. Also I tried different contact thickness and stiffness inside this card, and make a little gap between SPG and FEM part. Nothing of these helped. Could anyone tell me why under just gravity loading the specimen start to move after some model time and accelerations are increasing? Looks like SPG method is very unstable at all.</p><p>You can download one of my input files with this link: https://drive.google.com/file/d/1xFyWjedxMHNY_ZBJ_B3iyiObG0ng53Bl/view?usp=sharing</p><p></p><p></p><p></p>
<p>Hi </p><p>I got the d3plot and d3max files using R16.2 lsdyna, but when I am checking the result, I found the effective stress of d3max mtach the d3plot, but the effective strain, pricipal stress, pricipal strain all can't be matched. Why?</p><p>Firstly, I use the R14, they didn't macth, then I use R16, they still didn't match. The d3max updating time set same as the d3plot output time, and also set output the pricipal strain and pricipal stress. Could you help me to explain this issue?</p><p>Thanks</p>
<p>Hello, I would like to install LS-OPT; however, I was not able to find a source to download it or contact ANSYS support directly regarding the installation. I emailed ANSYS support, and they directed me here. Could someone please help me with this matter? Thank you for your time and support. </p>
<p>Hello everyone.<br>I'm simulating an urban blast calculation in the explicit module, but first I put together a small test problem.<br>I need help with some settings.<br>1. I have three solid bodies: a cylinder, a TNT charge (a sphere), and air (a cube surrounding everything).<br>The TNT charge and air are Eulerian solids, and the cylinder is a Lagrange solid.</p><p><br>The mesh has 70,000 elements.</p><p><br>2. I set the calculation time to 0.001 since the model is small. For a large model, the calculation time is 1-15 ms because it includes a large building.</p><p><br>3. I also adjusted the SPH speed time and the number of cells for my model, and I increased the number of result records to 200 (see images).<br>4. The calculation time is 10 minutes. I also configured the solver to Autodyn.</p><p><br>5. I display the results: Total Deformation (for the body around the charge), Pressure (expression), ALPHAALL (expression).<br>These are the results I see:</p><p></p><p></p><p></p><p>6. Now I want to see how the explosion waves propagate and make a nice animation, like this:</p><p></p><p>How do I do this?<br>Thanks!</p>
<p>Hello all,</p><p>I am trying to use a compiled solver from the usermat version of LS-DYNA. Initially I had some issues compiling the solver with the Makefile, but after adding some lines to the LIBS variable in the Makefile, I was able to compile something. However, when trying to use the file made with the Makefile, with LSrun, I get a license error.</p><p></p><p>I tried some of the suggested solutions from previous posts, such as:</p><p>export ANSYSLMD_LICENSE_FILE=127.0.0.1</p><p>env ANSYSLMD_LICENSE_FILE=1055@127.0.0.1</p><p>In the lsout file, it says "license option:check ansys licenses only" at the top. I am using the usermat version of R13.1 mpp double precision. I also saw an "ansyscl" file was mentioned. If this is needed, where would it be located when downloading the compressed folder? Is it supposed to be inside the compressed folder? I am unable to find file. Also looking in the license tab of LSrun shows licences are active and are waiting to be used.</p><p>Best,</p><p>K</p>
<p>I am running a Hypervelocity Impact simulation of a projectile impacting an assembly built with Constrained nodal rigid bodies and Beam elements to represent the bolts.</p><p>When I run the model without setting a Control_termination endtime (so just initialise the model with a velocity applied to the impactor) it will initalise normally and terminate normally. But when I include the Control_termination endtime keyword and run the model, it will initialise but then all the solid elements which are connected to my CNRB fail on the first timestep.</p><p>Could someone help explain why this might be the case please?</p><p>For context, the model is built from entirely solid meshes (quad and tet for different parts), and the elements which are failing are those connected to a second order solid tetrahedral mesh (the mesh was generated in hypermesh and imported to LS DYNA) - for this part I am using a Solid Section with ELFORM 16 following literature I found online. </p><p> </p><p>Thank you!</p>
<p class="isSelectedEnd">Hi everyone,</p><p class="isSelectedEnd">I am running a windshield impactor test in LS-DYNA using <code dir="ltr">*MAT_ELASTIC glass shell elements with <code dir="ltr">*MAT_ADD_EROSION.</p><p class="isSelectedEnd">The erosion card includes a critical stress, critical strain energy, and critical radius. My understanding is that when a glass element reaches the critical stress, LS-DYNA evaluates the accumulated strain energy within the specified radius around that element. If this accumulated strain energy exceeds the critical energy, the related elements are eroded.</p><p class="isSelectedEnd">For my study, I want to keep the critical energy very high so that erosion does not occur, and I want to post-process the time history of this accumulated strain energy during the windshield impact.</p><p class="isSelectedEnd">However, I cannot find this quantity in the output. I can only see part-level <code dir="ltr">internal_energy from <code dir="ltr">MATSUM, but this is not the local strain energy I need.</p><p class="isSelectedEnd">How can I get this strain energy output in LS-DYNA?</p><p class="isSelectedEnd">Thank you</p><p class="isSelectedEnd">Ali</p>
<p>Hello, I've created a model to calculate the pressure on a hull during a water entry.</p><p>I've used S-ALE method and on my PC it works, I get pressure measures using DATABASE_FSI keyword and then exporting the csv files.</p><p>I have to get a bigger analysis of a complete structure impacting water and I use a MPP.</p><p>I've just tryed to run the same analysis (the one which works on my pc) on the MPP but I can't get the dbfsi file I need.</p><p>The plot I get in post processing are just many plots all with the same values which are not correct, they are all equal to the results of the first sensor I've placed on the bottom of the shell element. The dbfsi doesn't appear in the ASCII files and so I have to select the BINOUT option and import the "results".</p><p>I don't understand what I'm doing wrong, the run files are the same but the results I need don't appear</p><p> </p><p></p>
<p><p>Hello all,</p><p>I been having the same issue as described by Atish Gawale in a previous post: running simulations on a linux graphical interface through lsrun, where running on SMP single precision worked fine, but got a forrtl: severe (174): SIGSEGV, segmentation fault occurred when trying to run on MPP double-precision.</p><p></p><p>Has anyone found a fix/reason for this issue?</p><p>I have tried different versions of LS-Run and solver executables, and I still get the same issue: same error message w/ MPP, but it works w/ SMP.</p><p>My simulation has no contact, it is a cubic lattice undergoing displacement controlled uniaxial compression. </p><p>Best,</p><p>K</p></p>
<p>Greetings!</p><p>I'm attempting to simulate a simple model: a cylindrical specimen under gravity load supported by a rigid plate in <span style="text-decoration: underline;">LS-DYNA SMP double precision</span>. The plate is fixed in all degrees of freedom. The SPG parameters are set as follows: KERNEL=2, ITB=3, MSC=1, PDAMP=-0.001, DX=DY=DZ=1.6. Despite its apparent simplicity, the model exhibits instability after about 0.06 seconds. The specimen begins to move without any reason (no changes made to the model). I've noticed unphysical oscillations in acceleration values - they start to grow to extremely high values (1e06 m/s^2 and more) and I don't know why. I tested different SPG parameters (different KERNEL, ITB, MSC, DX, DY, DZ values) but the issue remain unsolved. Also I tried to include some damping to model (PART_MASS, PART_STIFFNESS, FREQUENCY_RANGE) but nothing helped. The contact between SPG part (specimen) and FEM part (plate) is defined using DEFINE_SPG_TO_SURFACE_COUPLING card. Also I tried different contact thickness and stiffness inside this card, and make a little gap between SPG and FEM part. Nothing of these helped. Could anyone tell me why under just gravity loading the specimen start to move after some model time and accelerations are increasing? Looks like SPG method is very unstable at all.</p><p>You can download one of my input files with this link: https://drive.google.com/file/d/1xFyWjedxMHNY_ZBJ_B3iyiObG0ng53Bl/view?usp=sharing</p><p></p><p></p><p></p>
<p>Hi </p><p>I got the d3plot and d3max files using R16.2 lsdyna, but when I am checking the result, I found the effective stress of d3max mtach the d3plot, but the effective strain, pricipal stress, pricipal strain all can't be matched. Why?</p><p>Firstly, I use the R14, they didn't macth, then I use R16, they still didn't match. The d3max updating time set same as the d3plot output time, and also set output the pricipal strain and pricipal stress. Could you help me to explain this issue?</p><p>Thanks</p>
<p>Hello, I would like to install LS-OPT; however, I was not able to find a source to download it or contact ANSYS support directly regarding the installation. I emailed ANSYS support, and they directed me here. Could someone please help me with this matter? Thank you for your time and support. </p>
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