Nonlinear Material in Hypermesh [Optistruct Tutorial]

[@mashutka1983]

It is very helpful for me. Thank you a lot

[@Aeroswap]

Glad it was helpful :)

[@emmanuelvassilakis5630]

Hi Swapnil! Nice presentation of a case with material nonlinearity. The only thing I would add for the non experienced FEA users attending your channel is a comment about the curve used: "engineering" vs "true" stress-strain. Also, for material NL analysis one may use only the plastic part of the stress-strain curve of the material. Thank you.

[@Aeroswap]

Thanks Emmanuel! Right, I should have put a note about the difference between 'engineering' and 'true' SS curves. I will probably pin a comment about that to highlight its importance to all the viewers. As for the material curve, I doubt that there will be any change in the results if only plastic region is used (considering that only material nonlinearity is present in the analysis and not geometric/contact nonlinearity). Please correct me if I am wrong!

[@emmanuelvassilakis5630]

@@Aeroswap Hi Swapnil, thank you for your reply. No, I do not think there will be a change in the results if only the plastic region of the SS curve is used.

[@amindoxiti1201]

Good job, please keep going.

[@Aeroswap]

Thank you!

[@alexkou95]

Your tutorials help so much! Keep up the good work! Make videos about MBD with motionview and flexprep.

[@Aeroswap]

Thank you! I will work on these topics soon :)

[@allonmessenberg3129]

Great video. I have a few questions: 1. Why do you specifically request displacement and stress outputs in H3D format when those are produced by default? 2. Why do you export an FEM file and then solve it from the compute console instead of directly from Hyperworks? 3. Can you show the same analysis but with self-contact so the deformation and stresses when the 2 slits collapse and the edges contact each other can be visualized/extracted?

[@Aeroswap]

Thanks! Here are some points on the queries mentioned in your comment. 1. It is possible to extract results in multiple output formats from the same analysis (for example H3D and OP2). I am deliberately selecting H3D to keep everyone following the video on the same page, that's all! 2. To launch Optistruct from HM, it is necessary to have both the software installed in the same directory on the machine. This is already satisfied if you are using the same version of HM and Optistruct. However, if you want to use a different version of HM and Optistruct, you need to either map the location of solver in HM installation directory or lauch it externally as I did in the video. It is recommended to launch externally as this will not affect the performance of HM during the analysis run operation. 3. Thanks for this suggestion. I will definitely try it out and see how it goes! I hope this information answers your queries.

[@allonmessenberg3129]

@@Aeroswap Fantastic. Thank you.

[@cmgl2165]

Hi, Very good video and thank you for your time. One suggestion I would like to make however, is to highlight how important it is that the linear part of the curve only contains 2 points: the origin (0,0) and the first yield point. You see, I spent hours to realise this because I imported an experimental curve that had more than two points in the linear part and I was getting the following error: * ERROR # 3021 * The plastic material data specified on the TABLES1 bulk data entry ID=1 is invalid. The slope after the initial yield point is not less than the Young's modulus. All the best.

[@marciodinizdasilva]

Very nice job! Congratulation for your easy and didatic way to teach. Thank you very much. Have you any advise to run that analise using rubber? I want tu performe a test and "calibrate" the proprities.

[@CP-zi3eg]

Very useful videos... keep on !! I would like to ask how to change the color of background, in a similar color of Hypermesh environment. Hyperworks uses a too brilliant background color in my opinion. Thank you

[@adelinewar3222]

Hello your videos are really simple to understand and helpful. Can you please make a video on Batch mode between Hypermesh and Matlab. Also videos on TCL Scripting.

[@DoppioBlue]

Hi great video. I try to import the csv file as you have showed but the curve editor is empty. Do you have any suggestion? Or can you show the table in the file csv? Many thanks

[@gouthamsridhar123]

Can you please do videos on Non linear simulations in Radioss? For instance, how to determine and select the various contact parameters for Inter Type 7. Really appreciate it! :)

[@baboudielmehdi9749]

Sir what it the use of External Material data? does it impact my results? I used the same Methode without the table(external data) and I did not recieve a non lineare curve

[@Aeroswap]

Hi there, By external material data, do you mean the stress-strain curve in CSV file format? You can also create your own stress-strain curve in Hypermesh using the Utilities browser. Then there is no need to import it from external files. However, if you don't use any curve, you are essentially defining a linear material so the analysis results may not be accurate. I hope this helps!

[@vladimirlubimov2318]

Hello! It's a great job!! Thank you so much for your videos and lessons. Excuse me, but could you help me? Please tell me which type of material is better to choose for EPP (Expanded Polypropylene) material. It is used as an energy-absorbing material, in particular as an organizer in the trunk of cars for tools, as well as for inserting under the bumper. I know its characteristics (Young's modulus, density, Poisson's ratio and there is an experimental stress-strain curve). I am very grateful to you in advance.

[@PhilipeRadeckFoltran]

There is no MATS1 option for MAT8 composite material, is there a way to use non-linear property curves for composites?

[@Aeroswap]

MAT8 is a linear orthotropic material card, so yes, there is no nonlinear input in that. I'm not sure which card supports nonlinear orthotropic materials. Maybe it is MAT9, but please check once before using.

[@phrfolt]

@@Aeroswap I contacted Altair and currently Optistruct does not support non-linear orthotropic materials. They also included that it is in order for the development team to implement this feature, so maybe in the future. Thank you for your videos!

[@Aeroswap]

Thanks for the information. Good to know!

[@Buzz_Mustermann]

Could somebody tell me, if there is a way for a size/ shape/ topology optimization for non-linear material behaviour ONLY using optistruct? I cannot find any videos or resources in the web for general nonlinear (material nonlinearity) optimization for optistruct combined with hyperstudy. If there is a way ONLY using optistrict it would be great.

[@user-ri9ti4eh2u]

do you give private lessons ?

[@abineshdamodaran3910]

Is we can expect in future for Abaqus and hypermesh combined videos ?

[@Aeroswap]

Yes, I do plan to create tutorials for other solvers like Ansys and Abaqus soon :)

[@allonmessenberg3129]

@@Aeroswap Please focus on the Altair ecosystem. There's a huge amount of Ansys tutorials on youtube and other platforms, but you are the only real source for Hyperworks tutorials.

[@ezzeddinekaroui3170]

@@allonmessenberg3129 I confirm that. I'm following swapnil for months and he is very pure-heart person (I contacted him via e-mail) with good explanation skills. Keep going bro

[@prasoonkumar9154]

How to capture fracture of any component? Like ductile or brittle fracture in tensile testing.

[@emmanuelvassilakis5630]

By "fracture" you mean to see the displacement and the "opening" on certain parts of the component during post processing? If yes, then an appropriate failure material law is required with the option to delete every element that has exceeded a certain stress limit defined by the user.

[@nguyenminhvo8820]

Can you send me the csv and model files. Thank you

[@anupamajayan3052]

Hi, need the csv file...