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<p>Hello, in using define_SPH_Injection_(option), how can I properly define contact between generated SPH particle and the FEA body?<br><br>There's no clear indication of the set being generated, I tied using part ID but no luck/crash.</p><p>I appreciate the advice</p><p>Thank you! </p>
<p>I am learning about the S-ALE mapping as an alternative to traditional full restarts, and I would like a specific example keyword to learn this method。</p>
<p>Hi there</p><p>Try to use python for postprocessing through LS PrePost. My understanding is the first step is to do set pythonhome stuff. However, it keeps saying that the python home is not valid. I have tried different python installation locations and computers.</p><p>I am using LSprepost v14.2, v4.10.3 with python 3.14.</p><p>Thanks</p>
<p>Hi everyone,</p><p>I am running a Finite Element Analysis using ANSYS Workbench (LS-DYNA extension). I’ve encountered an issue where the exported .k file automatically includes the *CONTROL_BULK_VISCOSITY keyword, even though I haven't manually added this card in the outline tree.</p><p></p><p>This keyword is significantly affecting my simulation results. When I manually delete it from the .k file and run it via the solver manager, the results align perfectly with my expectations. However, I want to find a permanent way to disable or modify this within the Workbench interface to avoid manual editing every time.</p><p>My questions are:</p><p>Where is the setting located in Workbench to suppress or remove *CONTROL_BULK_VISCOSITY?</p><p>Is there a default setting or a Command Snippet that might be triggering this?</p><p>Any insights would be greatly appreciated. Thanks!</p>
<p><p>Hello,</p><p>I created a dome composed of many beams and made a cylinder crash the dome. When I set the initial velocity as -30, the result looks good. But if I change the velocity to -60, there will be penetration between the parts. Does anybody know how to fix it? Thanks.</p><p></p><p>This is my .k file: https://drive.google.com/file/d/1gcOm7990HbWrbmrTTb4MAMjXJa-HI0xn/view?usp=sharing</p><p> </p><p></p><p> </p></p>
<p>Anyone knows how to get the reaction forces of thoses particules who collides?</p><p>I used the DATABASE_DEFORC card and *DATABASE_BINARY_DEMFOR with the complement dem="dem_interfaceforce"</p><p></p>
<p><p class="MsoNormal">Hello there,</p><p class="MsoNormal">I have a model in which an indenter penetrates a cubic material. The indenter is a rigid body and the cube is SPH node. I also used a node_to_surface contact. For the penetration, I want the indenter to move downward for 5mm. So, I used the PRESCRIBED_MORION_RIGID and also defined a curve (for displacement, so x axis is time) as follows:</p><p class="MsoNormal">(0,0)</p><p class="MsoNormal">(1.1,-5)</p><p class="MsoNormal">The termination time is 1. The problem is that the indenter stuck in 2.5mm and does not move downward to 5mm which I applied. I have tried several contact parameters but no changes happened (still get stuck in 2.5). After that I tried the following displacement curve and time:</p><p class="MsoNormal">(0,0)</p><p class="MsoNormal">(1,-5)</p><p class="MsoNormal">(2.1,-5)</p><p class="MsoNormal">The termination time is 2. The output of this simulation was different and the indenter moved downward more that 2.5; however, it is now goes to 10mm. Which is more that the prescribed displacement in curve. </p><p class="MsoNormal">I would be very grateful if someone can help in this regard. Am I applying the displacement in a wrong way? Is the curve wrong? Do I understand the prescribed_motion_rigid keyword wrongly?</p><p class="MsoNormal">I do appreciate any feedback and advice. </p></p>
<p>Hello all,</p><p>I am trying to model prestressed concrete member and was wondering if you can help me with how to apply the prestressing force. I am using the mat cable for the strands which has an option of initial tensile force so thought that would be enough to apply. However some papers suggest using thermal method by introducing keywords such as MAT_ADD_THERMAL_EXPANSION and LOAD_THERMAL_LOAD. I am not sure which method is the correct way but if the second method is the one then I am getting error in the process. Please see attached screen shot for the first method.</p><p>Thanks for your help</p>
<p>Hello, in using define_SPH_Injection_(option), how can I properly define contact between generated SPH particle and the FEA body?<br><br>There's no clear indication of the set being generated, I tied using part ID but no luck/crash.</p><p>I appreciate the advice</p><p>Thank you! </p>
<p>I am learning about the S-ALE mapping as an alternative to traditional full restarts, and I would like a specific example keyword to learn this method。</p>
<p>Hi there</p><p>Try to use python for postprocessing through LS PrePost. My understanding is the first step is to do set pythonhome stuff. However, it keeps saying that the python home is not valid. I have tried different python installation locations and computers.</p><p>I am using LSprepost v14.2, v4.10.3 with python 3.14.</p><p>Thanks</p>
<p>Hi everyone,</p><p>I am running a Finite Element Analysis using ANSYS Workbench (LS-DYNA extension). I’ve encountered an issue where the exported .k file automatically includes the *CONTROL_BULK_VISCOSITY keyword, even though I haven't manually added this card in the outline tree.</p><p></p><p>This keyword is significantly affecting my simulation results. When I manually delete it from the .k file and run it via the solver manager, the results align perfectly with my expectations. However, I want to find a permanent way to disable or modify this within the Workbench interface to avoid manual editing every time.</p><p>My questions are:</p><p>Where is the setting located in Workbench to suppress or remove *CONTROL_BULK_VISCOSITY?</p><p>Is there a default setting or a Command Snippet that might be triggering this?</p><p>Any insights would be greatly appreciated. Thanks!</p>
<p><p>Hello,</p><p>I created a dome composed of many beams and made a cylinder crash the dome. When I set the initial velocity as -30, the result looks good. But if I change the velocity to -60, there will be penetration between the parts. Does anybody know how to fix it? Thanks.</p><p></p><p>This is my .k file: https://drive.google.com/file/d/1gcOm7990HbWrbmrTTb4MAMjXJa-HI0xn/view?usp=sharing</p><p> </p><p></p><p> </p></p>
<p>Anyone knows how to get the reaction forces of thoses particules who collides?</p><p>I used the DATABASE_DEFORC card and *DATABASE_BINARY_DEMFOR with the complement dem="dem_interfaceforce"</p><p></p>
<p><p class="MsoNormal">Hello there,</p><p class="MsoNormal">I have a model in which an indenter penetrates a cubic material. The indenter is a rigid body and the cube is SPH node. I also used a node_to_surface contact. For the penetration, I want the indenter to move downward for 5mm. So, I used the PRESCRIBED_MORION_RIGID and also defined a curve (for displacement, so x axis is time) as follows:</p><p class="MsoNormal">(0,0)</p><p class="MsoNormal">(1.1,-5)</p><p class="MsoNormal">The termination time is 1. The problem is that the indenter stuck in 2.5mm and does not move downward to 5mm which I applied. I have tried several contact parameters but no changes happened (still get stuck in 2.5). After that I tried the following displacement curve and time:</p><p class="MsoNormal">(0,0)</p><p class="MsoNormal">(1,-5)</p><p class="MsoNormal">(2.1,-5)</p><p class="MsoNormal">The termination time is 2. The output of this simulation was different and the indenter moved downward more that 2.5; however, it is now goes to 10mm. Which is more that the prescribed displacement in curve. </p><p class="MsoNormal">I would be very grateful if someone can help in this regard. Am I applying the displacement in a wrong way? Is the curve wrong? Do I understand the prescribed_motion_rigid keyword wrongly?</p><p class="MsoNormal">I do appreciate any feedback and advice. </p></p>
<p>Hello all,</p><p>I am trying to model prestressed concrete member and was wondering if you can help me with how to apply the prestressing force. I am using the mat cable for the strands which has an option of initial tensile force so thought that would be enough to apply. However some papers suggest using thermal method by introducing keywords such as MAT_ADD_THERMAL_EXPANSION and LOAD_THERMAL_LOAD. I am not sure which method is the correct way but if the second method is the one then I am getting error in the process. Please see attached screen shot for the first method.</p><p>Thanks for your help</p>
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