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<p>Hello,<br><br>When I perform explosion simulations using the particle blast method (PBM), I create the explosive model using *DEFINE_PARTICLE_BLAST and collect the position, density and pressure data of explosive particles using *DATABASE_PBLAST_SENSOR. The keyword file is shown in Figure 1. According to the description of *DATABASE_PBLAST_SENSOR in the keyword manual, the collected position, density and pressure data should be saved under the pblast_sensor branch in the binout file. When I view the binout file using LS-PREPOST, the pblast_sensor branch is displayed, but no data is visible, as shown in Figure 2. When I convert the binout binary file to an ASCII file, the converted file contains only headers and no data, as shown in Figure 3. The d3hsp file after the calculation is shown in Figure 4.What could be the reason for this? How can I obtain the data under pblast_sensor?<br><br>Thank you.<br><br><br><br></p>

<p>Hello,</p><p>Further to my question regarding access to the AWG group pages, I'm getting the input files presenting a possible workflow for obtaining the initial stress state of a rotating engine part (described in § 5.1.1 and § 5.1.2 of the document LS‐DYNA® Aerospace Working Group "Modeling Guidelines Document" version 24.1).</p><p>I'm doing the same thing with my model, but I'm unable to obtain a steady state for my rotating part at the end of the second step. The main difference is that my model includes *ELEMENT_SHELL_OFFSET elements. So, I simply modified my input file by replacing the *ELEMENT_SHELL_OFFSET elements with *ELEMENT_SHELL elements, and the behavior seems much better, except for the triangular elements, which still don't reach the steady state.</p><p>Two questions at this point:</p>Is it possible to use a prestress analysis following the workflow presented in the AWG document with offset shell elements and enabling additional options ? I need to use shell offset element as I will work with composite parts modelled with ACP.How do I handle the problem with triangular elements? (My part is a cone, which will be difficult to mesh with only quad elements, but not impossible, I admit.)<p> </p><p>Best regards,</p><p> </p><p>Jérôme</p>

<p data-start="200" data-end="207">Hi all,</p><p data-start="209" data-end="401">When modeling soil layers as an elastic material in LS-DYNA, I would like to define the stiffness (e.g., Young’s modulus) as a function of depth — specifically, the <em data-start="374" data-end="377">z-coordinate in my model.</p><p data-start="403" data-end="612">I noticed that the *MAT_ELASTIC card supports defining stiffness as a function of an elemental variable using <code data-start="513" data-end="520">EFUNC. The manual gives an example using <code data-start="556" data-end="565">EFUNC=P to define stiffness as a function of pressure.</p><p data-start="614" data-end="868">However, in my case, I would like to define stiffness as a function of the <em data-start="689" data-end="692">z-coordinate. After searching the manual, I suspect the correct keyword may be <code data-start="770" data-end="776">"CZ", but this is based on hints from other keyword descriptions and I’m not completely certain.</p><p data-start="870" data-end="1036">Could anyone confirm whether <code data-start="899" data-end="905">"CZ" is indeed the correct variable to use for referencing the z-coordinate in <code data-start="980" data-end="987">EFUNC? Any clarification would be greatly appreciated.<br><br></p><p data-start="870" data-end="1036"></p>

<p>Could anyone tell me where to find the Mean Ipt effective strain which I show below <span style="font-size: 18.6667px;">in LSDYNA</span><span style="font-size: 14pt;">? I can't find it in my d3plot file.</span></p><p></p><p>The corresponding setting in my keyword is also demonstrated here:</p><p></p><p></p><p></p><p>My ASCII defined the output of ELOUT/GLSTAT/MATSUM/NCFORC/NODOUT/RCFORC/SECFORC.</p>

<p>Hello everyone, I am modelling composites for impact simulations but i am unable to validate existing literature. I have alligned the fibers into desired direction as well.</p><p>I have given eroding surface to surface contact between projectile and composite layers and automatic surface to surface tiebreak between composite layers.</p><p>After the impact, the elements of one composite layer are falling into other without maintaining the proper contact (image below). How can I solve this issue?  What other possible errors could be there for my simulation to not match the previously published results apart from the material properties. Would symmetry plays a major role in results. I have set 3 boundary conditions, fixed and x and z symmetry by restricting the degree of freedom for respective case.</p><p>Thankyou</p><p></p>

<p>Hello,</p><p>Just a piece of information: the AWG pages are unreachable (error 421).</p><p>Hope the issue will be fixed soon. If you know a way to reach the pages with an another link, you are welcome.</p><p> </p><p>Jérôme</p>

<p>Hello everyone.</p><p>I'm trying to learn LS-Dyna. I've made the arrangements for my first simulation but when I launch the LS-Dyna and click on run the simulation I always get the terminated message. I've opened the command prompt window to see what's wrong and it seems to be a problem with a thing called lsdynamsvar.bat. I've checked the .bat file's path and the file isn't there. Apparently that .bat file is missing entirely how can I fix this ?????</p>

<p><p>Has anyone see how the newest LS prepost - 4.12.6 not updating the animation state bar?   basically, when you click on the triangle, the blue button doesn't move to the right at all.</p><p></p></p>

<p><p><p><p><p><p>I'm encountering inconsistent results when running the same LS-DYNA model file using the same software version (LS-PrePost(R) V4.7.7 - 17Feb2020, LS-Run 2021 R2). Even though I copy the model to a different directory and execute it with identical settings—same number of CPUs (NCPU) and memory allocation—I still get different outputs. What's more, I even get varying results when I rerun the model in the <em data-start="460" data-end="466">same directory. In such cases, LS-DYNA deletes the previous result files and generates new ones, yet the results still differ each time. The settings of running the folder are below.</p><p>The origional results - It shall be like this, this is the time-force curve:</p><p>I am using a shared memory parallel processing, the calculations may be executed in different order, depending on CPU availability and the workload on each CPU.  Therefore, I specify the number of CPUs as a negative number to maintain consistency. But I am getting completely different curves, even when I run the corrected file again. Please any suggestions to get the previous results back.</p>

<p>Is there a recommended way to show the contour of the 3 stress invariants inside LSPP using some type of user defined function? </p>