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![Pickup Truck Impact on Bollard [REUPLOAD]](/img/d.gif)
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Hello, i would like to ask. in my simulation the "bird" only goes through the blade and did not create an impact effect, how can i fix that?
@@sulthanraffi3738 I think this was already discussed in one of the other comments. Please check the comments of this video and let me know if you don't find it.
wow, awesome
thanks!
Dear Ameen, thanks for the interesting video. I would like to use such lattice structure to model a sandwich structure with a flat plate on top and bottom of the lattice and perform a low velocity impact analysis but i have two questions: 1) which is the best approach to bond the lattice core and the flat plate if it's not possible to merge nodes? 2) how can i avoid that the lattice structure penetrates itself?
@@user-rr3hq6yu9s 1) Use *CONTACT TIED NODES TO SURFACE 2) Use CONTACT AUTOMATIC SINGLE SURFACE
Excuse me. Do you know cohesive elements? I set my ice with cohesive elements and use a rigid part to impact on my ice. My question is when I set an Eroding single contact to simulate ice self-contact. My SPC boundary condition on ice just make no sense, ice cubes spread out directly after impact. Can you give me some advice? Thank you, your videos are very helpful for my article.
Sir iam getting the error of ALE part is beyond initial void what could be the reason. Thankyou
Are you using INITIAL VOLUME FRACTION or INITIAL VOID?
Initial void
@@akshayraj2426 the part used in this keyword should have ELFORM = 12.
Sir at the end of lsdyna manager it is showing like forttl severe program exeption acess violation
This sort of error is due to the solver, as discussed recently in the LSDYNA Gmail group. Check that one for more details..
Hi Sir. How do you adjust your cutting speed? Which keyword do you use and what setting is important there?
To impose the velocity on the tool use *BOUNDARY PRESCRIBED MOTION RIGID and *DEFINE CURVE. To change the velocity, change the values in DEFINE CURVE. These are the basics, I recommend you to watch my Tensile Test tutorial.
Hi, really impressed by your work. I have a question, I have a similar orthogonal machining model. I want my tool to follow a profile such that it starts with zero chip thickness, reaches maximum in the middle of the workpiece and returns to 0 chip thickness at the end of workpiece length. Can you suggest how to implement this in LS Dyna, I would be really grateful.
@@syedahsanadeeb7485 you can use *BOUNDARY PRESCRIBED MOTION to control the vertical displacement of the tool
I am a graduate student, thank you very much for your video, I benefited a lot from your tutorial called "Sphere Drop on Water". Can you share a tutorial for making waves with a board like shown in the video or Keyword? Thank you very much for your reply.
I am glad that my tutorial helps. Unfortunately, I don't have the time to make any video requests. With that being said, if there is a possibility for a research collaboration, then I might be able to support you. You can reach me out personally for this.
@@AmeenTopa Okay, thank you. I have sent you a friend application on linked. We can have further communication after you approve it.
@@mengdecao-b9d alright noted. I have a (backup account) on LinkedIn. Don't use that one.
thanks, it helps me a lots
@@wangxc9585 you are welcome.. Don't forget to cite my articles related to composite simulations 🙃
Hello! Сould you tell me, please, how can I quickly reduce the mesh? Or is it necessary to completely rebuild the model?
@@R.-RitaR to reduce the size of the elements, you can use the element tools to split the elements. To increase the size of the elements, you need to rebuild the model.
@@AmeenTopa Happened) Thank you very much!
hi thank you for the informative video! may I ask if it is possible to make multiple honeycombs to become a honeycomb structure inside of LS prepost in itself, since for my final thesis I am supposed to make a honeycomb structure, thus I imported from the honeycomb creator in Designmodeller, but it turned out to be individual shells that makes it difficult later in the material classification, thank you in advanced.
@@nathanprimana9580 you can use the same method in this video to create a single cell. Then, use the Transform -> Translate tool to make copies of that cell. It takes some practice but if you are good at geometry, then it should not be a problem.
Very excellent tutorial! May I ask have you tried using Structured ALE method to conduct FSI simulation?
@@dequan-g2z thank you. Yes, I use it as well. But I don't have any tutorials on it in my channel .
@@AmeenTopa Thank you for the reply!May I ask u, how to create a cylindrical SALE area? Thank you again!
@@dequan-g2z you need to make a box then trim the SALE domain.
@@AmeenTopa Is it conducted by *ALE_STRUCTURED_MESH_TRIM?
@@dequan-g2z bingo! That's the one.
Thanks
Thank you for the video. Can you please tell me when modeling an I -beam, how can i define the section in LS-DYNA?
@@ASMRJigsawJoy for modelling I beam using 1D elements, you need to use the user defined integration rule. Check *INTERROGATION BEAM in the user manual vol. 1.
@@AmeenTopa Thank you. I did the I-beam mesh by referring your round corners I-beam mesh video. So still can I use that user defined integration rule for a modeling for a blast analysis of an I-beam? Also for a one my modeling I have to use the materials which are, Structural steel: S355 to EN 10025-2, Concrete: C40/50 to EN 206-1, Reinforcement: B500 to EN 10080 and BS 4449. To define these materials in LS-DYNA how can I find the material properties of them?
@@ASMRJigsawJoy Okay, then we are talking about a different thing. Check my tutorials: - Reinforced Concrete Slab and Wrecking Ball (this will show you how to model reinforcement and how to define concrete material) - TNT Blast on Composite Beam (this will show you have to model I-beam using solid elements) - Modal Analysis of Stiffened Panel (this will help you on how to model I-beam using shell elements)
Hello,sir! I would like to ask you that if you can tell me how to conduct the FSI of Air-backed steel plate subjected to underwater explosion? I am confusing that the overlapping area between Lagrangian mesh grid and the ALE mesh grid. Thank you so much!
Check my tutorial on TNT Blast on Composite Beam.
@@AmeenTopa Thank you so much!
@@dequan-g2z no problem!
Hi, I have a rock that appears to have a hypervelocity micro impact crater on it. Would you be able to identify this feature on a rock?
can you do about the of thin-walled prismatic structure subjected to inclined impact load ? do you have any documents about this subject ?
@@duypham4360 Sorry, I don't have any tutorials related to that specific topic. If you practiced this tutorial, as well as the other videos in the LSDYNA BASIC TUTORIALS playlist on my channel, I believe you will be able to do it yourself. Unfortunately, I don't have the time to make video requests. With that being said, if you need personal help, I am available for consultation. But there will be some fees, of course.
Do you have any video on contacts or modeling screws in a steel beam? Thanks for sharing 👍. good video.
@@Ingeniero8206 I don't have a video on that but you can check the following presentation www.dynamore.de/de/fortbildung/konferenzen/vergangene/2018-ls-dyna-forum/forum-2016-de/m-02-schenke-dynamore-mod.pdf
@@AmeenTopa Thank you, greetings from Chile 👍
very clever and nicely done
@@Martijn-m8r thanks!
@@AmeenTopa I am a structural engineer for buildings. But it is educational and nice to see how other fields work🙂. Really a beautiful model Ameen!! Is the model you made used to determine the stresses in the ship? And determining fatigue damage. Can the waves also act at an angle to the ship? Then there are also torsional forces on the ship, right?
@@Martijn-m8r I am glad that you found it interesting.
I wanted to ask, how can I increase the number of SPH particles for a model already created on LS-Dyna? As I intend to make some changes to an existing model. Do I have to start from scratch once again if I want to increase the number of particles?
I wanted to ask, how can I increase the number of SPH particles for a model already created on LS-Dyna? As I intend to make some changes to an existing model. Do I have to start from scratch once again if I want to increase the number of particles?
Yes, you need to delete the particles and create them again.
You said q=d3crack, but could you tell me how to do it with the current version instead of the old version? Please, I am a self-taught student in Korea😂
@@user-dc5cm1kc8h do you mean you use LS-RUN? If so, then you can add this command in the expression line.
I typed "$SOVER" i=$INPUT ncpu=$NCPU memory=$MEMORY Q=d3crack, and the d3crack file size is 0. What should I do, teacher😢
@@user-dc5cm1kc8h have you defined DATABASE BINARY D3CRACK? Also, this crack file is supported only with MAT WINFRITH.
Full video
@@rfrmnsyh this is a very old model. I didn't record the steps while creating it..
Hello sir , when I click on run button I get error as " Restart file is not found" What might be the issue?
@@shubhamkavitkar5738 you accidentally added d = d3dump in the run command.
@@AmeenTopa When I use another expression it is getting terminated
@@shubhamkavitkar5738 gets terminated with what error?
@@AmeenTopa negative volume in solid element. This error I am getting
@@shubhamkavitkar5738 try to use CONTACT ERODING SURFACE TO SURFACE.
Hello sir , when I click on run button I get error as " Restart file is not found" What might be the issue?
❤ great job 👍
Can you provide this tutorial？❤❤
I don't have a full tutorial on this. But you may check my tutorials: "Sphere Drop on Water" and "Sloshing Inside a Tank with ALE method". They will be very helpful.
Impressive, as always. Waiting for more tutorials *_*
Thanks!
what software is this?
@@NikhilSahu-w2f LS-DYNA
Hello first offall thank you for the video if i may i would like to ask one question what would change if i take the surfaces from space claim as stp and mesh it in ls dyna and what would happen if i model casing as euler part
@@batuhangokalp2763 yes, you can import STP files to LS Prepost. If the liner is ALE, then you need to connect it to the rest of the ALE domain via shared nodes.
it looks like a minions face
Hello ameen, now I am using LS-Prepost to make a closed cylindrical shell structure flow under water, I want to derive the water flow force on the structure, which should also be called the coupling force. How can I get this result? Thank you very much for your answer!
You are using the ALE method? If yes, then check my tutorial "sphere drop on water" and also my sloshing tutorial .
@@AmeenTopa Thank you very much, ameen!
@@AmeenTopa Hello ameen!I watched your video to do the simulation of the ball drop, and finally used the double precision mpp and single precision smp in ls-run to do the calculation, and the result in ASCII of the fluid-structure coupling force curve are always 0, I would like to know where the problem is, thank you very much for answering me!
@@AmeenTopa Ameen, I solved that problem just now by querying the keyword manual, I switched to a newer version of ls-prepost and set INTFORC to 1 in the LAGRANGE-IN-SOLID keyword and it worked!
@@user-je9lr1ut8b great! I am glad it worked! Sorry, I think I referred you to the wrong tutorial. The one that should be helping is the sloshing tutorial.
Hello sir, thank you for this video. I had a question regarding the ALE Air domain. What is the type of boundary condition that is implicitly applied here ? If I were to simulate confined blast in a cube chamber would modeling the cube by the air domain with one of the wall being a lagrangian structure generate the same results as if I were to fully model the cube as a lagrangian structure and put it inside a bigger ALE air domain ? Thank you very much for your content and answers
If it is a confined blast, then it is more efficient to not model the Lagrange cube. Just use *BOUNDARY SPC NODE SET or *ALE ESSENTIAL BOUNDARY to fix the outer surface of the air domain.
@@AmeenTopa Thank you very much for the advice !
@@AmeenTopa Hello sir, i'm sorry to bother you but you are truly of great help. I have two question for you and it would be awesome if you could answer them. 1 - How can I specify the initial internal pressure of the TNT so that the material is at atmospheric pressure at t=0 like the ALE domain ? 2 - I couldn't find in lsdyna a damage model that rely on elongation at break, are there any model like that ? Thank you very much for everything
@@theodose3 1 - I have no answer to this. You can try different values of E0 in the equation of state for the TNT. 2 - You may want to check ADD DAMAGE GISSMO.
@@AmeenTopa Once again thank you sir
Is there convenient method to display the Z-displacement of the top surface?
Click on F8 for the blank tool, blank (hide) or the elements of the top surface, then click on Reverse blank option and everything will be hidden except the top surface. Then go to Fringe contours.
@@AmeenTopa Thanks a lot.
Could you please explain how do you get the plots ?
Check my video: Post processing with LS-PREPOST
I was following the same steps on a problem with a bit different parameters. It is also a bird strike problem. But the following errors are showing in the messag file: *** Error 20136 (STR+136) Material 561 is coupled with with MADYMO ellipsoid 2 For MADYMO coupling, check y=madymo on the execution line *** Error 21342 (STR+1342) The Madymo coupling flag, N, for rigid part id 561 is greater than zero for a non-Madymo coupling simulation.
Are you using my human dummy models? If not, the problem is on MAT RIGID. You accidentally changed a parameter that you shouldn't. Basically, for this MAT, you need only to define RO, E, PR. CMO, CON1, and CON2 are needed only if you want to constrain the centre of the mass of the rigid body.
@@AmeenTopa Okay, thanks for this, I was defining an extra parameter n which caused this error. But now, the following error is showing up: *** Error 10146 (KEY+146) coordinate set id 7 is undefined CHECKING *MAT_RIGID INPUT Part ID= 561
There is still an error in the material model. Aside from the parameters I mentioned in my previous comment, leave everything as their default value.
@@AmeenTopa Yes yes, I corrected it. Its running now. Thanks for the help
@@sam2215 you are welcome and all the best.
very creepy wide smiling face at the bottom
Haha yeah. Numerical simulations can give you nightmares 🤣🤣
noted
Hii sir I am Akshay, i have seen your blast simulation video. I have also tried the same as yours, I am getting problem related to ALE multimaterial section ELform 11 is not applying over there. If another ELform kept like -2 or -1 the blast is going out of air domain. Sir I request you to please provide me the solution regarding the problem. Thankyou sir
Hi there, for the TNT and AIR, you need to use ELFORM = 11 in SECTION SOLID. If this option does not appear to you, then maybe you are using an old version of LS-PREPOST and you need to download the latest one. ELFORM = -2 and -1 are for structural parts like the concrete or steel parts.
@@AmeenTopa thankyou sir
For the 20 noded hexahedral, can you please show how two layers consisting of these serendipity elements can be bonded with tiebreak contact? I would like to define segment sets, but i have not been successful- it keeps giving me a master, slave segment error. Also, the option to use cohesive elements (ELFORM19) with 20 Hex is out of question, right? Could you please provide some guidance on the tiebreak contact for the 20 noded Hex?
Hello, great video. I have this error when running : *** Warning 41272 (SOL+1272) Please define a vacuum AMMG for converting the failed ALE materials Any idea what could be the issue ? Thanks
Does it happen at the very start of the simulation or after some time?
@@AmeenTopa At the very start, thank you for your extremely fast reply
Then, most probably there is something incorrect in the material properties. Check for typos or inconsistent units.
@@AmeenTopa Okay thank you. I also have another question : since i'm not used to meshing in ls dyna, I usualy do the cad file in solidworks/catia, import it in hypermesh to mesh it and export it to lsdyna. Could you explain me what are you doing around 5m30 ? Because for the meshing I simply meshed the surfacic cad file with mixed 2D elements in hypermesh, i don't understand why are you doing solid elements ? Thanks
@@theodose3 that is an intermediate step to create the liner. I created the solid, and based on that solid I created the shell part for the liner. Unlike Hypermesh, LS-PREPOST does not have the same meshing capabilities.
How to install LS-Dyna program manager sir
You need to purchase the LS-DYNA license from LSTC and they will give you the program manager. Alternatively, you can check my tutorial on how to get the LS-DYNA students version. It comes with LS-RUN which functions like the program manager.
Sir, can you make more video of ALE especially about ship slamming load
Unfortunately, I don't have time to make video request for my channel. You may check my tutorial: Sphere Drop on Water. That video will help you in modelling slamming. Lastly, I am available if you need personal help but there will be some charges.
@@AmeenTopa About personal help, how can I reach you sir?
@@MuhammadSyafaAdana You can contact my team at [email protected] Or, you can directly message me through my LinkedIn or Facebook.
@@AmeenTopa thank you 🙏
I recently follow you on LinkedIn
Have you tried the 27 noded element?
Yes, I tried that one but it was giving instability errors.
In ls dyna How to provide displacement value. Where did I find that option sir?
Check my tutorial: - LS-DYNA TUTORIAL 2: Tensile Test
Is this geometry or mesh available somewhere?
@@andregf The bollard geometry was created from scratch. For complete vehicles FE model, you may check the links below: www.ccsa.gmu.edu/models/ www.nhtsa.gov/crash-simulation-vehicle-models Also, check my Car Collision tutorial. I have include more links in the description of that video.
@@AmeenTopa thank you sir
Thank you for these tutorials i am learning LS-dyna for my phd, you have been a huge help.
You are welcome and all the best for you PhD! Please check my research articles and cite them if any is related to your research 😁😁
Respected Sir, Sir how can i apply force on the CENTER OF MASS of a model. Also is there any option to relate all model nodes to a point.
For the first question, if the body is rigid, then you can use *LOAD RIGID BODY. For the second question, you can use*CONSTRAINED NODAL RIGID BODY. Check my tutorial on Tube Impact on Rigid Wall.
@@AmeenTopaThank you sir for your suggestions Sir your second suggestion I had tried but it didn't give the desired output. Will try the first suggestions sir ❤.
@@kushagrakumar6054 you are welcome and all the best!
Respected Sir, When I am using a high speed bullet on the plate (900 m/s), I observe no change in the plate i.e no Von misses stress. The bullet enters and leaves the plate without any impact on the plate. Can you please explain it why and also provide a solution for it. Thanks.
For high velocity impact, you need a small time step size. Try to reduce TSSFAC in CONTROL TIMESTEP + reduce the elements size.
@@AmeenTopa it worked..thanks
@harshnavangul2060 you are welcome! If you are working on a thesis or a research article, kindly cite my papers related to composite materials. 😁 - Ansari, M. N. M., K. S. Vinoth, Afeefah Nordin, Alaseel Bassam, and A. Topa. "Tensile properties of hybrid kenaf/glass fiber reinforced epoxy composites with different stacking sequence using experimental and FEA simulation method." In IOP Conference Series: Materials Science and Engineering, vol. 1128, no. 1, p. 012023. IOP Publishing, 2021. iopscience.iop.org/article/10.1088/1757-899X/1128/1/012023/pdf - Bokhoeva, Lyubov Aleksandrovna, Aldar Batomunkuevich Baldanov, Vitaly Evdokimovich Rogov, Anna Sergeevna Chermoshentseva, and Topa Ameen. "The effect of adding nanopowders on the strength of multilayer composite materials." Factory laboratory. Materials Diagnostics 87, no. 8 (2021): 42-50. www.elibrary.ru/item.asp?id=46475169 - Pavan, Raut, Anerao Prashant, Topa Ameen, Munde Yashwant, Avinash Shinde, and Irulappasamy Siva. "Numerical simulation of low-velocity impact test on PALF/Epoxy bio-composite laminates." Materials Physics & Mechanics 50, no. 1 (2022). mpm.spbstu.ru/userfiles/files/10-Raut-Pavan%2C-Anerao-Prashant-et-al.pdfwww.academia.edu/download/98039757/6472.pdf - Gungor, Emre, Ameen Topa, and B. O. Kucukyildirim. "Numerical Investigation of Innovative Honeycomb-Composite Sandwich Structure Under Bird-Strike Event." In 6th International Conference On Advances In Mechanical Engineering Istanbul. 2021.
@@AmeenTopa Sir your work is absolutely amazing. Can I use materials like Glass fiber for my research regarding bullet armors? I also wanted to get some research papers that have all the properties of Kevlar or Twaron fiber so that i can do a simulation in LS Dyna. If possible can you pl provide me with it?
@@harshnavangul2060 you may search in the website dynamore for articles that use LSDYNA.
Thank you for your videos. They are a great help in learning LS-DYNA. Its just that I am unable to visualize the stress and strain results. Its showing 0 stress and 0 strain, thus no variation is denoted. Do I have to do something else to get them?
Do you see deformation in the propeller? Make sure the interaction (contact) works between the bird and the propeller.
How do I ensure that?
@@AmeenTopaI am unable to see the deformation. How do I check the contact between the propeller and the bird?
@@sam2215 did you miss the part in the video where I defined the contact card?
@@AmeenTopa I rechecked it, but I am still unable to see the deformation in the propeller
it looks amazing!
It is! Subscribe to my channel to support me so that I can make more awesome videos :)a