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Hi, I am a PhD candidate in Mechanical Engineering at Purdue University implementing a user defined material (umat41) for LS-DYNA MMALE simulations of granular flow. Ansys Support (Kristy, ACE Customer Operations) replied on September 21, 2026 that academic support is provided through this forum, which is why I am posting here. I understand the ftp.lstc.com/objects credentials cannot be shared. Following the earlier thread "Request for access to dyn21.f file for research project", could an Ansys employee download the matching usermat package and send it to me directly? The Download Center carries the LS-DYNA solver binaries but not the usermat packages. Solver: lsdyna_dp_mpp.e from Purdue's Ansys 2026 R1 installation, revision R16.1.1-32-g1f25c69f9c, Linux x86_64, MPP, double precision, SSE2, Intel Fortran 19.0, Intel MPI 2018.3.222, sharelib. Expected package name: ls-dyna_mpp_d_R16_1_1_x64_centos79_ifort190_sse2_intelmpi-2018_sharelib.usermat.tgz_extractor.sh The license is Purdue University's academic license. I can share our Ansys customer number privately and am happy to continue by email at gngo@purdue.edu.

Dear all, I was wondering whether there is a way to define an isotropic power-law model using the *ICFD_POROUS_MODEL keyword, as is possible in Fluent, for example. The current card only seems to offer the Ergun and Darcy–Forchheimer models. I would appreciate any guidance you could provide on this. Thank you in advance for your help. Best regards, Gred

這是模擬器平衝壓成型的過程，外面還有一個外模具，我的沖壓頭會一直穿過鋁片，前面都已經試過contact了，後面用body interaction還是會穿過去 

Hello, We are running an academic license server for our university on a desktop machine. We have been using our academic license for more than a decade without any issues up until 9/7, after which point our computers have been unable to connect and communicate with the license server. The server is running in the desktop machine, the license file has not expired, and the IP address of the license server is still the same as before.  Please let me know what needs to be done so that we resolve this issue.Many thanks in advance.

近期想設置6061在LS Dyna的材料模型，但不知道從哪裡可以找到正確的悟性表

I want to access the user assigned element numbers from the input card deck from within a user-defined material. I can access the LS-Dyna internally assigned element numbers via the idele variable but I do not know how this internal element number maps to the user assigned element number.  Can you please instruct me how to access the user assigned element numbers from within the user-defined material? What array or variable to I need to access?  I tried using the "Ansys Assistant" but it did not produce any solutions to the above problem.  Thanks!

Dear Anyone, I know it is an odd request but it appears that LSPP is no longer accessible and I'm looking for another version of it.  Is there a way a non-client of ANSYS can get access to LS-PrePost? Thank you, George

I am simulating the impact of discrete element (DEM) particles on a wire mesh structure in LS-DYNA. The particles are generated using *DEFINE_DE_INJECTION. The structure consists of a frame modeled with solid elements (*MAT_ELASTIC) and wires modeled with beam elements (*MAT_PLASTIC_KINEMATIC). The keyword file was initially generated using ANSYS LS-DYNA (where meshing was also done) and finalized in LS-PrePost. For structural contacts, I defined *CONTACT_AUTOMATIC_GENERAL and *CONTACT_AUTOMATIC_NODES_TO_SURFACE. For the DEM-to-structure interaction, I implemented *DEFINE_DE_TO_BEAM_COUPLING and *DEFINE_DE_TO_SURFACE_COUPLING. However, during the simulation, the DEM particles completely penetrate both the wires and the frame as if the structure does not exist. Are there any missing keywords or specific parameter adjustments required to properly enforce the physical interaction between the DEM particles and the structure?

Hi, I wanted to ask about the contact with the rigid wall. I think I’m getting a bit confused about it. I have SPH particles in contact with the rigid wall, and based on my searches, I think I should change RWPNAL. The problem is that, despite having friction on the rigid wall, the particles slide along the wall. In this case, RWPNAL was set to 1. I changed RWPNAL to -1, and now the particles pass through the rigid wall. I chose -1 based on the following description: "The optional penalty method for rigidwalls, invoked by setting RWPNAL=-1.0 in *CONTROL_CONTACT , works identical to the contact-impact interface treatment. When a deformable or a rigid node is found to be penetrating a rigidwall, the penetrated distance along the rigidwall normal is computed and is resisted by applying a force that is proportional to the computed distance and multiplied with a stiffness factor that is based on the material of the impacting node and the dimensions of the element it is attached to. The penalty approach conserves both energy and momentum".  How should I resolve this issue? I want the SPH particles to interact properly with the rigid wall. Thank you,

I am using 3D tet remeshing in a FEM application and I can only get a uniform element size in the entire body. I have tried to change "MM" in keyword *CONTROL_REMESHING but it does not matter what value I use I still get a uniform element size. Since I need to use small elements on the surface to get the contacts to work I get a very large number of elements in the body. Is there any way to get the tet element size to grow from the surfaces?