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Hello.The project involves impacting a tennis ball (made from hyperplastic rubber with internal pressure) against pre-tensioned tennis strings (made from polyester and nylon) at a maximum velocity of 265 km/h in a direction normal to the string bed. Observing the stress and deformation, the objective is to determine the thinnest possible string for the two materials under test. I thought of conducting multiple steps from simple to more complicated toward the main project:  1-Testing the solid ball(with Ansys predefined Explicit>Rubber-2 material) against a rigid plate :  -body interaction: proximity-based frictionless-mesh  -ball velocity: 7m/s-plate displacements=0 -analysis setting: end time: 2e-2automatic mass scaling=nomax no of cycles: 1e7 RESULT:The ball bounced back when hitting the plate   Issue 1: when we increase the speed(50m/s), some ball elements penetrate and get stuck into the plate, preventing the ball from rebounding. we tried refining the mesh but the issue insisted. issue 2: we acquire the tennis ball and polyester string material properties(stress-strain curve) but assigning it to them gives us an error.     error: "You have specified result time(or frequency) = 0.00226447262556333 for a result file which has maximum time(or frequency) = 4.19585521740373e-05.  If you specify 0(ZERO), the solution for the final time will be displayed."issue 3: Regarding applying a pretension force on the string in the main analysis, we have difficulty effectively applying it. I attached the verification(Ball_impacting_plate), the main project file and the materials stress-strain data. Materials are also already added to the Engineering Data of the verification file.Main ProjectBall Platepolyester stress-strain curveRubber Stress-strain curve I appreciate your help.Thank you

Hello,does somebody how any example of hyperelastic law with fibers implemented into UMAT? What IHYPER and AOPT i should use for such analysis? I have made such UMAT for NH with polynomial density function for one family of fibers, but results are not convergent with Abaqus.Best regards,Tomasz

Hi everyone. I am making a model that glass breaks under pressure. Is it correct to define the load in DEFINE_CURVE and LOAD_BODY_Z ㅁas shown in the picture below? I look forward to your reponse. Thanks.

  What error could this be? license/info] Successfully checked out 1 of "dyna".[license/info] --> Checkout ID: HHDHS2011106802[license/info] Successfully started "ANSYS_LSDYNA".  *** Error 70022 (OTH+22)           Please file a Service Request (SR) via the ANSYS Customer     Portal at https://support.ansys.com.           Customers using an academic license may seek assistance     at https://forum.ansys.comE r r o r   t e r m i n a t i o n

Hello community,I struggle to perform a LS-Dyna restart in which I would like to add geometry.Via the external model I import the dynain file of the LS-Dyna simulation I want to restart.To achive that I renamed the dynain file to dynain.k (also tried dynain.dat)Vie the mechanical model I want to add geometry.I get this error:Conversion Failed. [C:\ANSYSDev\TFSAgent\_work\2\s\CodeDV\ModelConversion\ModelConversionLib\Acmo\AcmoMeshProvider.cpp:80] ElementEnumeratorImpl: No elementsThe error only shows up when the external model is connected.Does someone know how to fix that?If needed, I will happily provide further information.

Hi everyone. I want to apply pressure to the glass and break it. I don't know how to apply pressure. Could you give me an example related to this? Thanks.

Good afternoon,I am trying to simulate a CFRP Cloth layer impregnated on concrete in AUTODYN for a ballistic performance test. If anyone can help me, what material from the standard material library would best suit a CFRP replica?I have reviewed some literature and tried created my own materials based of this, but everytime I try to run my program it states "initializing" and then crashes.. I am now resorting to a pre-loaded materialAny help is greatly appreciated

The package we are looking for is Intel Parallel Studio XE 2017 (2017 version) with Intel Fortran Compiler 17.0.Any information would be appreciated

Hi,We want to change our palette in the fringe plot by loading a palette file. We would like to make the colorbar color-blind friendly, but we could not find anything about what this file would look like. If there's a pre-built file we can try, that would be very helpful! 

My research requires that I use a development version of LS-DYNA, which I receive from ANSYS personnel and update on a semi-regular basis. Last year, my institution's LS-DYNA license was connected with an LSTC license file, which was appropriately referenced by our supercomputer in a file named LSTC_FILE, which has the following format: #LICENSE_TYPE: network#LICENSE_SERVER: <port_number>@<host_address> This LSTC_FILE was (and is) located in the same directory as the development builds of LS-DYNA, and, prior to this year, I was able to run a variety of analyses using thse development versions of LS-DYNA. This year we have been unable to connect our valid license files with these development versions of LS-DYNA. Originally, we simply had an ANSYS license file that has LS-DYNA functionality supported, but referencing the appropriate host and port yielded a licensing error. We have now received an LSTC license file (in addition to, but not clearly necessary) to accompany our ANSYS license file and connected this with the original server/port that hosted our LSTC license last year. We anticipated that this would have solved the problem. However, I am still receiving an error message stating   *** License problem *** Network license:  *** Error License client cannot find any servers to talk to.               Servers may be down, not ready, or the wrong version.    *** Error 70022 (OTH+22)  Nonetheless, ncat commands indicate that the connections on our needed to find both the LSTC and the ANSYS license files are working. Furthermore, basic run commands also appear to work successfully on the non-development version of LS-DYNA that we have installed. I have screenshots demonstrating this, but for privacy reasons choose to not post them here. We have tried modifying our LSTC_FILE with each of the different ports and addresses necessary to refer to these license files, but to no avail. At this point, we are at a loss on how to access the software.  1. With the change of the year, did a "hello" message necessary to communicate with the license change?2. Do we need to modify the format of the LSTC_FILE, or refer to this license some other way?3. Should we just be able to use our generic ANSYS license file to run these beta versions of LS-DYNA, or do we need the LSTC license file to run these executables? We have both licenses, and both are being found from our login node, but for some reason the executables are not recognizing these licenses. How can we proceed in getting our license issues resolved?

Hello,my question is related to 1-step reaction in CESE solver.Do we need to define single reaction in CHEMKIN format file or is there any other way to define same?Do we need to use CHEMISTRY_CONTROL_CSP or CHEMISTRY_CONTROL_FULL keyword?Thanks,Atish

Hi I performed an explicit analysis where an object (elastic wood) hits a tank steel shell with 3 m/s. After t = 0.04 sec, this is the energy plot I got. My question is whether this energy plot seems okay. One of my colleagues said that kinetic and internal energy plots tell us about explicit analysis whether it is successful or not. 

I'm trying to simulate a bone block being cut by a burr. I want to use an ALE method to simulate this. Currently I'm running into issues when setting up the connections tab of the simulation because in the frictional contact the selections for target and body stay yellowed out. I'll attach screenshots of the contact and geometry definitions. I added a coupling between the two but I don't know what that does or if it helps.

I'm trying to use the SPH method to simulate a burr cutting bone-block. I want to capture a 50 ms ramp time of the burr. The main issue I'm seeing is that the burr is just disappearing from the simulations after 4.997e-2. I'm new to Ansys and don't know what could have caused this. Any help would be much appreciated. 

I am working on electromagnetic railgun launching, and my LS-DYNA simulation produces negative volumes as soon as the current is applied. Why is this happening?

I have set up a FSI simulation using the S-ALE keywords. I am replicating the method used in the following paper to find the added mass of a floating body.https://doi.org/10.1016/j.marstruc.2016.05.005With a coarse mesh of 1m size for the ALE elements, the simulation runs fine with the timesteps remaining almost consistent throughout the entire simulation.But when the S-ALE mesh is made with progressive spacing, such that at the free surface of air and water, the element size reduces to 0.4m, the timesteps drop from the initial calculated timestep. How to identify the cause of this problem and resolve it to have a consistent timestep throughout the simulation?I am currently using the default settings PFAC=0.1 for the coupling.

As recommended in the S-ALE tutorials, I would like to set up the Fluid-Structure interaction using the *ALE_STRUCTURED_FSI keyword, with a load curve defined for the penalty coupling pressure.1.Is there any way to roughly estimate the coupling pressure? 2.As recommended in the guidelines, I have tried to set the curves by defining two points, one at origin and the other with (absicca = 1/10 ALE element size, ordinate = Pmax). Does this coupling pressure refer to the total pressure at the fluid-structure interface or does it only refer to the additional pressure due to the coupling?When we have a submerged structure with a large draft, the hydrostatic pressure in the ALE domain will contribute significantly to the total pressure. So does this Pmax on the load curve have to include the hydrostatic pressure?3.Since leakage control is automated in the new S_ALE FSI keyword, how to identify in a simulation if the set coupling pressure (from the load curve) is adequate or if the automated leakage control is getting activated?

Hi,I'm curious about how the proximity selection tool criteria is defaultly defined. I've been searching for information on this matter but haven't been able to find any. For instance, in my model, it's automatically set to 2.47885 mm.I imagine it has something to do with the average element size in my model... Thanks

Dear community,I try to set up a full Ls-Dyna restart in workbench.Furthermore, I want to activate/deactivate parts for this restart.I tried the following keyword snippet to delete parts:$   Keyword Snippet$   Do not leave any unintentional empty lines in this editor*DELETE_PART60910, 60912, 21573, 21571, 21941*ENDUnfortunately that did not work.I also tried construction stages:*DEFINE_STAGED_CONSTRUCTION_PART60910, 0, 1*DEFINE_STAGED_CONSTRUCTION_PART60912, 0, 1*DEFINE_STAGED_CONSTRUCTION_PART21573, 0, 1*DEFINE_STAGED_CONSTRUCTION_PART21571, 0, 1$PARTID: 60910, 60912, 21573, 21571*DEFINE_CONSTRUCTION_STAGES0, 0.0, 0.5, 0.0, 0.0, 0.5*DEFINE_CONSTRUCTION_STAGES1, 0.5, 0.55, 0.0, 0.5, 0.55*ENDThat did not work either.However, I did not get any errors in the solver output.I look very forward to your suggestions.

If you use the spg unit to initialize the confining pressure loading stress and set the spg unit bond base to break, will there be stress fluctuations in the remaining units after the bond base breaks?

I've recently been attempting to insert my code into an existing EXEDIT subroutine in Autodyn, aiming to achieve temperature transfer functionality within a 2D multi-material Eulerian domain. However, upon execution, it seems that my code isn't producing any noticeable effects. Below is the portion of code I've inserted into the existing EXEDIT subroutine:I would like to know if this functionality can be implemented through a user subroutine, whether it should be written in an EXEDIT subroutine, and how to modify model parameters during the calculation process and return them to the main program to continue the calculation.Version: ANSYS 15.0; VS 2010; Fortran 2011Operating System: Windows 10 ProfessionalThank you to everyone who can provide assistance. I truly appreciate your support and guidance!

As part of my project I had performed an analysis of a circular fabric plate. I had conducted the analysis by providing horizontal, vertical and cross slits at the centre of the plate with varying geometry. So when I checked the results, as the width of slit increases the stress is reduced for the horizontal and vertical slits and in case of cross slits initially the stress increases with increase in slit size, then stress decreases with increase in slit size. Why does it happen like this?Also, instead of slit when providing hole in the centre with varying diameter, the stress value shows initial increase in stress with decrease in hole dia and changes the pattern for small diameter. What could be the reason for this?

Hello all,I am running a simulation using LS-Dyna with *LOAD_NODE_SET and constraining some DOF at distinct ends with *BOUNDARY_SPC_SET. Following some recommendations given on previous posts, I am using a ramp to define the curve and then use a constant value (see graph below). To check the quasi-static condition, I am using glstat and matsum to verify that the kinetic energy is below 5% of the internal energy; this is true for glstat and for matsum only one part had high kinetic energy.My question comes from checking some variables (see graph below for v-m stress of just 2 elements, whole part rigid-body motion) for which I observe this weird oscillating behavior that prevents me to obtain confident results at the end of the simulation; naturally I am expecting a line that shows results converging to a value (similar to my loading curve). Has anyone experience a similar issue like this? Is this caused by the ramp application curve... maybe it's too fast? Or maybe it's a lack of boundary conditions? Any idea would be greatly appreciated.Also a follow up question. I noted there's an option for rigid-body acceleration in the history variable option: I have nonzero (still relatively small considering my time units) values for some parts. Is zero acceleration also a condition for quasi-static behavior or is the internal vs kinetic energy ratio sufficient?   

Hello,I want to model a semi infinite fluid domain using ambient elements in SALE mesh. I have created a solid set using SET_SOLID_GENERAL and the mesh control points required. While defining the *BOUNDARY_AMBIENT keyword, is it mandatory to input the Load curves for Internal energy and Volume fraction? When the pressure inflow/outflow in the ambient boundaries are unknown, can the LCIDs for internal energy and volume fraction be left blank? 

Hello, I'd like to ask some questions related to the AUTODYN energy deposition subroutine EXSIE. I have a two-dimensional copper target with grids of 500 and 100 in the I and J directions, respectively. The energy deposition of each grid is different and is entered by reading a text file.As shown in the picture of my subroutine code, my idea is to call this subroutine once in each loop, and then enter the energy deposition corresponding to I and J, but in fact, this is not the case. Can you help me to see what's wrong?What I want to calculate is to import it into each grid of the copper target through external energy deposition, and then calculate the changes in density, pressure, temperature and so on over a certain period of time. And then I have another question that I want to know is that when I look at the cloud map of the calculation, the temperature is always zero and there is no change.The picture shows the external energy deposition that I want to import. The first and second columns are XBI y coordinates, and the third is energy deposition.