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@geardyn-1 yeah, I'm not sure how well Dyna can simulate something like wear. Have you read this? It might be something more suited for Abaqus?

I would like to know how to make the model with overlapping nodes between adjacent elements in LS-PrepPost. Simply put, it is like the FE model loaded in the sample below. The background to this question is that we would like to consider fracture based on *CONSTRAINED_TIED_NODES_FAILURE instead of ADD_EROSION. I would be appreciated if anyone have any solution for this.

Hi @george-m, It looks like you have your gravity load curve flipped. It needs to be positive not negative, which I know seems backwards but it's just the way LS-Dyna handles global load direction. Below is a thread and I've also linked the dyna examples page.

Hello , Bird strike analysis requires a little bit learning of lsdyna in order to debug the impact behaviour. i would suggest you to go through the examples first , which are available in Lsdyna example website, SPH simulation is better to this soft body analysis. PLease go through the link below for better understanding:

Hi, I was simulating the deflection of a diaphragm with uniform pressure acting on it. Fig 1 I am doing an axisymmetric 2D simulation. We expect the solution to converge as given below with increase in mesh elements. Fig 2 While meshing, when I increase elements in the radial direction, keeping only one mesh element in the thickness direction as below, with an increase in the element size, I am getting an increase in deflection, which matches the classical curve shown in Fig. 2. Fig 3 But the moment I mesh in the thickness direction as Fig 4, the trend changes and deflection decreases as shown in Fig 5. When the number of mesh elements increases, we assume less stiffness and more deflection. But why is deflection not increasing, as shown in Fig 5, when we start to refine mesh in the thickness direction? Thank you, Sreejith

HI @negativevolume Could you share the pdf file to which the link you have shared? I don't have access to the site. And I really have an issue with non convergence of my implicit analysis

I imagine you have already looked to youtube and found videos like the one by this site's creator or Ameen Topa's channel. If so, and you're still having issues. . . . well, the fact there is no text at all on your plots kiiiiiinda has me thinking you PrePost color settings were at some point changed. You might have white text on a white background. Have you tried making sure that is not your problem yet?

Hi @sarvin, Have you checked out either of these links? The first is a link to a material selector where you input the element formulation of the part that you will assign the material and then the general type of material you want. It'll also give some high level description of each one.

@Jacob_22, personally I have not taken any courses on LS-DYNA but rather just struggled through basic examples presented on Youtube and extended that same methodology to the LS-DYNA examples that you mentioned. This youtube channel has been the most helpful for me with regards to setting up a basic model: This channel has also been helpful, specifically for the theory behind contacts: There is also the theory manual for LS-DYNA that goes into detail about most of the inner workings of LS-DYNA but I will warn you that it is not an easy read: I will point out that ANSYS has some general courses (not specific to LS-DYNA) that cover the basics of FEA: I personally have used the ANSYS learning hub to take many courses related to ANSYS (fluent, autodyn, mechanical) and they were all very informative and helpful, you can also potentially get six months free for the student ANSYS learning hub if you contact them directly. Most of my learning with LS-DYNA has been through downloading the models from the examples page, trying to re-create them, and changing parameters to see how they influence the model. I will add that if you dont know there is the pre-post processor in LS-DYNA called LS-PREPOST that I have found to be essential for navigating all the options available in LS-DYNA. I hope some of this information is helpful!

Hi @willjust, I'm not familiar with "must read" books in that field but that seems like a solid choice to get you started. I'm a pretty visual learner myself so I would do some digging into any free course through universities. MIT has a load of free courses here with a particular lecture that you may like here. There are others, but MIT probably has the most comprehensive collection. And since we are in the Careers section, I might as well give some career advice. If you are interested in ballistics, put APL (Johns Hopkins Applied Physics Laboratory) on your radar. They do a ton of work for the US DoD. Maybe contact them and show you have some interest? Or even apply to an internship?

Hi @bhattarai, It really depends where you are trying to extract the stress/strain from. You are correct that you can use the fringe component to analyze these but you can also use the ascii or binout output from ELOUT which you activate in the *Database_elout. I've linked a video below which goes over how to add elements to the *Database_history_solid in order to output the stresses and strains in the elout. (Implementation starts at 20:55 in the video) This document may help answer any detailed questions regarding ELOUT from solid elements Let me know if you have any more questions.

@samuele-libralato Great news! Soft=2 and depth=5 is usually my go-to setting for any contacts that I'm having issues with. You can use it for single_surface contacts as well as surface-to-surface. Soft is just a label, it's not actually softening the contact. Soft=2 changes the contact to a segment-based contact, not figuratively but mathematically. What I mean is that figuratively, you can define a contact with segment sets, but soft=2 is changing how contact is detected between surfaces. This write up will go deep into the details: I'd also suggest using this page as a guide as well. It's a lot, but can be helpful. And of course, feel free to ask if you have any more questions!

@icebreakersours MetaPost through Beta (who makes Ansa) actually has an AR/VR mode that I believe is pretty solid? Never used that part of the software but use Meta all the time. Here's a link to the website and the Metapost VR brochure.

@delcon You could try to add some implicit cards to improve convergence. Try some of these guidelines and see if anything helps.