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<p>Hi, I am trying to reconstruct an impact simulation in LS-DYNA (using LS-PrePost) I found described in a research paper. The simulation looks at the impact behaviour of a tube being axially crushed by a rigid impactor. The tube consists of two shells representing a composite tube. In the paper it is described to constrain the translational degrees of freedom of the bottom nodes of the tube (two shells). However, if I run the simulation the tube is still being pushed in the direction of the moving impactor. I activated the LAMSHT flag in the CONTROL_SHELL card which seemed to help initially, however, after a bit more crushing the tube seems to break free again and move with the impactor. I suspect this to be caused by the fact that only the bottom-most nodes are being fixed, which causes translation of the tube as soon as these nodes break free from the main section of the tube. Still, I don't understand how the paper was able to do this... Is there a setting that might solve this? Also, I have read about using a RIGIDWALL_PLANAR to simulate the boundary condtions, would this work and would it change much of the solution? </p><p></p><p>Thank you for your help and time. </p>

<p>I defined "*ALE_STRUCTURED_MESH  # 1" and "*ALE_STRUCTURED_MESH # 2" with *ALE_STRUCTURED_MESH and coupled them to the same Lagrange unit as ALE_STRUCTURED_FSI # 1 and ALE_STRUCTURED_FSI # 2 respectively，I set TDEATH=20 for *ALE_STRUCTURED_MESH # 1, *ALE_STRUCTURED_MESH # 2 TDEATH=default, when the calculation time reaches 20 the program will *ALE_STRUCTURED_MESH # 1, ALE_STRUCTURED_FSI # 1 and ALE_STRUCTURED_FSI # 2 were deleted at the same time, which caused my calculation failure. The specific error is shown in the figure. How should I set the keywords so that the program only removes *ALE_STRUCTURED_MESH # 1 and ALE_STRUCTURED_FSI # 1 and let the program continue? What I mean is that the program automatically removes ALE_STRUCTURED_MESH # 1 and ALE_STRUCTURED_FSI # 1 and then ALE_STRUCTURED_FSI # 2 and the Lagrange cell continue to function until I reach the computation termination time I set.</p>

<p>Hi, I am trying to recreate the impact of a carbon fibre hull with water. I would like to use MAT 054 to better simulate the mechanical characteristics of the fibre, but I can't find any source from which to take the values to enter in the XC XT YT section. Is it possible to calculate them theoretically or is it necessary to carry out mechanical tests?</p>

<p>I used "*ALE_STRUCTURED_MESH_MOTION, OPTION = FOLLOW_GC", I want the mesh to move with the fluid, how should I set an initial velocity for the fluid in the mesh？</p>

<p>Hello,</p><p>I just installed a stand-alone license of ANSYS on my home computer.  The geometry window in ANSYS Workbench appears to be missing the numbers on the distance scale at the bottom of the window, as well as the numbers on the contour bar legend (see screenshot below).  How would I reset this view to make all the values appear?  </p><p>Thank you,</p><p>D</p><p></p>

<p>Hello,</p><p>I want to run simulation using LS DYNA MPP double precision solver. I need help with the expression line. How to define number of cores to 16? Is it using -np 16 in the expression line as shown below?</p><p></p><p>Regards,<br>Atish</p>

<p>Hello,</p><p>I am running my simulation on HPC using interactive graphics mode using LS-DYNA CESE solver. I am getting the following error and the run terminates instantly. Could you please help to resolve the issue?</p><p>forrtl: severe (174): SIGSEGV, segmentation fault occurred.</p><p></p><p>Regards,</p><p>Atish</p>

<p>Hello, </p><p>I am doing a crash impact structure simulation, and I decided to bond the structure with the body as follow (with formulation MPC):</p><p></p><p> </p><p>It seemed to work when I was using 12 layers of CFRP:</p><p></p><p>But when I wanted to test with 30 layers of CFRP for the front impact structure, the connection did not work..</p><p></p><p> </p><p>My questions are:</p><p>1) What should I change? What have I done wrong?</p><p>2) In my case, I would like to specify the car structure as a rigid body, but then I cannot bond a rigid body with my crash structure, is that normal?</p><p>3) I wonder what is better for my application to setup the test, ANSYS Workbench like I am doing (with ACP Pre and Mechanical Model) or should I use LS-Prepost? What is the most precise?</p><p> </p><p>Thank you, </p><p>Tristan</p>

<p data-start="133" data-end="138">Hi,</p><p data-start="140" data-end="240">Our lab is experiencing an issue where all workstations fail to run LS-DYNA, displaying the error:</p><p data-start="244" data-end="301"><em data-start="244" data-end="299">Server may be down or license service is not running.</p><p data-start="303" data-end="540">After investigation, we found that the issue is likely caused by a recent university network upgrade that changed our workstation IP addresses. The host (server) machine can still run jobs successfully, so the license itself is active.</p><p data-start="542" data-end="630">Can you help us add the following IP range to the <code data-start="592" data-end="605">server_data to resolve this issue?</p><p data-start="632" data-end="689"><strong data-start="632" data-end="649">New IP range:<br data-start="649" data-end="652"><code data-start="652" data-end="687">129.128.134.000 - 129.128.134.255</p><p data-start="798" data-end="993">Additionally, I have generated a new <code data-start="835" data-end="853">LSTC_SERVER_INFO file, but the forum does not allow attachments. Could you please let me know who I should contact directly and where I can send the file?</p><p data-start="995" data-end="1024">Thank you for your support!</p>

<p></p><p></p><p>Hi. I'm having difficulties with exporting the velocity profiles in Ansys CFD-Post.</p><p>My velocity profile plot has many sharp edges and I want to make it smoother. </p><p>I'm looking for a way better than using finer mesh, such as make more datapoints, or interpolated values.</p><p>I created a line and tried to get values with "slice" and "1,000 samples" but there was no difference, and I couldn't make more samples than 1,000 points.</p><p>Is there a way to get smoother (interpolated) plot or export with more than 1,000 samples with csv files?</p>