Dear Ameen, I am running a drop impact simulation of a composite structure against a rigid wall and modelled the my composite material with MAT54 card and the controls as in the video. I noted that during the analysis the time step starts to reduce when some elements start to fail. Consequently, the computation time increase a lot. Have you any suggestions to manage this issue? How can I stop the time step reduction to a certain limit?
Hello, I'm working on final year project on this topic. I need to use Glass fibre Epoxy composite and im facing trouble finding the properties (Youngs modulus shear modulus and poison ratio) for my material. From where can i get properties. Reply would be highly appreciated
Thank you for the video! Have you ever dealt with *MAT162? I can’t fully understand whether, based on this material, one can say about the delamination of the structure. My task is to simulate delamination and progressive destruction of the composite. Tell me, what materials (in Ls-dyna) can I use for this? Thank you in advance.
With MAT162, you can check the delamination through the history variables. For further information, check out this article: www.ccm.udel.edu/wp-content/uploads/2022/07/MAT162-USER-MANUAL-Version-22B-2022.pdf
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 ❤.
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.
@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?
Hi, I have a question about the initial velocity application. You used the card INITIAL VELOCITY GENERATION to the sticker in the video. What is the difference between INITIAL VELOCITY GENERATION and INITIAL VELOCITY?
Dear @@AmeenTopa, thanks for your reply. I would like to add a new question: you created single FEM parts for each of the layers and then assigned the material and ply orientation. The question is: after this operations, is it possible to include all layers in a single FEM part? Will it be the same from an analysis point of view? Will orientations assignment be mantained? Thanks in advance for your answer and for the time you dedicate to all users' questions.
@@AntonioGarofano-x7k Yes, you can use MoveCopy tool to make all layers into one PID. This should not make any difference in the results. The reason why I made it different layers is because this way it is easier to change the element orientations. Take note that if all solid layers are a single PID, then you cannot make it hybrid composite (for example, some layers are carbon fibre and others are glass fibres).
@@Mecharena188 it depends on many factors. I have no sufficient information to give you any recommendations. I don't even know which research paper you are talking about.
@@Mecharena188 material properties of the plate is not everything. You need to make sure that the impactor has the same geometry, mass, and initial velocity. Also, the boundary conditions should be exactly the same as in the reference. With that being said, replicating the data in research articles is not an easy task.
Hello, thank you for another amazing tutorial. I did everything step by step exactly the same way as you have. But when I run it, it gets terminated and gives an error saying " *** Error 10141 (KEY+141) Load curve id 1178684496 is undefined" in the lsrun.out.txt. Do you have any ideas on why it could be giving me this error? Thank you.
I think there is an error in the file when it was saved. The input files are given in the video description, please download one of them and compare it to your model.
sir, i have faced the same problem. this is because the properties *MAT_054 in line 9 (04:43) isn't given. but i am wondering why it must be given. However, when i pressed accept, the line 9 would dissappeared CMD would be Error 10141 (KEY+141)
Sir, i have few questions about low velocity impact test. How can i apply strikers initial energy to plate? For example while im making my test. my initial speed is 3.9 m/s and it has 120 joule energy but my plates are only absorbing 80 joule or smtn. how am i gonna make that absorbing value 120 joule ?
@@AmeenTopa In the analysis I conducted on the program, the force I obtained was around 25-30 kN, whereas my instructor obtained 17,000 N in the experimental analysis. I'm applying contact between each plate and impacting my striker as shown in the video. I've determined friction coefficients between the plates as 0.61 and 0.47. How can I reduce this force? What could be the reason for this? Could my epoxy resin values be incorrect? Thank you in advance.
Dear Ameen, thanks for all your tutorials.
You are welcome.
thanks, it helps me a lots
@@wangxc9585 you are welcome..
Don't forget to cite my articles related to composite simulations 🙃
Dear Ameen, I am running a drop impact simulation of a composite structure against a rigid wall and modelled the my composite material with MAT54 card and the controls as in the video. I noted that during the analysis the time step starts to reduce when some elements start to fail. Consequently, the computation time increase a lot. Have you any suggestions to manage this issue? How can I stop the time step reduction to a certain limit?
You can use ERODE = 1 or 11 and DTMIN between 1 - 0.
Hello, I'm working on final year project on this topic. I need to use Glass fibre Epoxy composite and im facing trouble finding the properties (Youngs modulus shear modulus and poison ratio) for my material. From where can i get properties. Reply would be highly appreciated
Check this article: www.sciencedirect.com/science/article/abs/pii/S0263822317320470
Thank you for the video! Have you ever dealt with *MAT162? I can’t fully understand whether, based on this material, one can say about the delamination of the structure. My task is to simulate delamination and progressive destruction of the composite. Tell me, what materials (in Ls-dyna) can I use for this? Thank you in advance.
With MAT162, you can check the delamination through the history variables. For further information, check out this article:
www.ccm.udel.edu/wp-content/uploads/2022/07/MAT162-USER-MANUAL-Version-22B-2022.pdf
Could you please tell how did you calculate Xc, Xt, Yc, Yt and Sc? Your reply would be appreciated
These values can be found experimentally through tensile and compressive tests.
I get it, these are the properties of your composite.
@@muhammadsaad7190 yes, each composite laminate has their unique strength limit values.
Thanks brother.
@@muhammadsaad7190 you are welcome.
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.
Hi, I have a question about the initial velocity application. You used the card INITIAL VELOCITY GENERATION to the sticker in the video. What is the difference between INITIAL VELOCITY GENERATION and INITIAL VELOCITY?
They are the same. But INITIAL VELOCITY GENERATION has more options.
Dear @@AmeenTopa, thanks for your reply. I would like to add a new question: you created single FEM parts for each of the layers and then assigned the material and ply orientation. The question is: after this operations, is it possible to include all layers in a single FEM part? Will it be the same from an analysis point of view? Will orientations assignment be mantained?
Thanks in advance for your answer and for the time you dedicate to all users' questions.
@@AntonioGarofano-x7k Yes, you can use MoveCopy tool to make all layers into one PID. This should not make any difference in the results.
The reason why I made it different layers is because this way it is easier to change the element orientations.
Take note that if all solid layers are a single PID, then you cannot make it hybrid composite (for example, some layers are carbon fibre and others are glass fibres).
Hi ameen , how to reduce the oscillations of plate after impacting, because of more oscillations the graph is not that crt
How do you know it is not correct?
From research paper
@@Mecharena188 it depends on many factors. I have no sufficient information to give you any recommendations. I don't even know which research paper you are talking about.
I tried to take properties from research paper and I got the graph, but the graph is not matching
@@Mecharena188 material properties of the plate is not everything. You need to make sure that the impactor has the same geometry, mass, and initial velocity. Also, the boundary conditions should be exactly the same as in the reference.
With that being said, replicating the data in research articles is not an easy task.
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, thank you for another amazing tutorial. I did everything step by step exactly the same way as you have. But when I run it, it gets terminated and gives an error saying " *** Error 10141 (KEY+141) Load curve id 1178684496 is undefined" in the lsrun.out.txt. Do you have any ideas on why it could be giving me this error? Thank you.
I think there is an error in the file when it was saved. The input files are given in the video description, please download one of them and compare it to your model.
sir, i have faced the same problem. this is because the properties *MAT_054 in line 9 (04:43) isn't given.
but i am wondering why it must be given. However, when i pressed accept, the line 9 would dissappeared
CMD would be Error 10141 (KEY+141)
Sir, i have few questions about low velocity impact test. How can i apply strikers initial energy to plate? For example while im making my test. my initial speed is 3.9 m/s and it has 120 joule energy but my plates are only absorbing 80 joule or smtn. how am i gonna make that absorbing value 120 joule ?
The initial energy = kinetic energy = 0.5mv^2.
So, you can increase the mass of the striker in order to increase the initial kinetic energy.
@@AmeenTopa In the analysis I conducted on the program, the force I obtained was around 25-30 kN, whereas my instructor obtained 17,000 N in the experimental analysis. I'm applying contact between each plate and impacting my striker as shown in the video. I've determined friction coefficients between the plates as 0.61 and 0.47. How can I reduce this force? What could be the reason for this? Could my epoxy resin values be incorrect? Thank you in advance.
The difference in the force is too much. Double check the properties of the composite laminates and the stacking sequence @@eraydogruoglu0
Sir, can i get your e-mail ? I want to ask you something about my final year project.
You can reach me out personally through facebook or LinkedIn.
Or, you can email my team at cae-works@outlook.com