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Lenny last won the day on July 3 2017

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  1. Hello, Thank you for your Suggestion, but that was not it. However, I found the Problem, which was kinda weird. TMINPLY was set to Zero as Default. However, I noticed another value in the opticontrol Panel coinciding with the value that was off: The Minimum Density. The Minimum Density is set to 0.01 as Default and thus, plies in the FreeSize-Optimization do not go lower than 1% of their original thickness. This is however illogical and plain wrong. The density of the plies does never change in the FreeSize optimization. So applying this Opti-Control Value to this optimization type is both illogical and confusing and I believe this should not be intentional. Do you believe this is supposed to be this way, even though FreeSize does have nothing to do with element density? I fixed it for me so it does not affect me anymore, but do you think I should contact Altair for a potential bug Report? (I am not using the most recent Version so I am not sure if this happens in the recent Versions as well) Thank you for your help! Regards, Lenny
  2. Hello Rahul,, Thank you for your answer! Although I am sorry but this does not quite cover the issue that I am having. I understand that FreeSize Optimization does sometimes yield weird non-discrete ply thicknesses. So I might rephrase my question: is it a known phenomen that during optimization the minimum ply thickness doesnever go lower than 0.1% of the original ply thickness OR Is this a visualisation issue within HyperView? if you may, please look at some optimizations and the lowest displayed values in HyperView. Does it ever go to 0mm? If not, Optistruct either never reduces the plies to 0mm thickness or it is displayed inaccurately in HyperView.
  3. Hello everyone, Sorry for bothering you again, but I encountered another issue which I am not able to resolve. I apply a thick Laminate of 72 plies to my part and let it run an optimization. However elements with no stresses should receive ply thicknesses of 0, alas "deleting" them. The Problem is, the lowest optistruct will go is 0.1% of the thickest ply. Say if my individual plies are is 5mm thick, the thinnest my plies will become is 0.05mm. This seems like to issue at first, but when working with 72 plies, this Comes out to a total of 0,36mm, which is indeed quite a lot! Is there any workaroudn for this? Using the PLYMIN FUnction in the FreeSIze Design variable yields no success (Presumably because it is set to 0.0 by Default). Any help would be greatly apprechiated. Greetings, Lenny
  4. Okay I figured it out. Appeartently it has to do with a bug in the Version I am using (14.0.220). However, using CBUSHes bypassed this Problem and I am able to to the Simulation as intended.
  5. Okay quick update - I figured it out: The Z0 Option in the PCOMPP Property Card can be set to REAL, TOP or BOTTOM. Using BOTTOM, the Laminate is placed directly on the surface which is great. However, now it tells me that this is not allowed for Free Size Optimization. How is this possible, or sensible at all? Is there a Workaround for this?
  6. Hello everyone, quick question that Google did not give me an answer for and I am a Little pressed for time. I have surface an would like to apply a stacked Laminate on top of it, so that the surface is used as base for the Laminate. However, whatever Setting I use, the Laminate always turns out to be symmetric, to each side of the surface. I cannot possibly work with a symmetric Laminate as I have constraints regarding the size of my part. The surface marks the outermost surface of my part and thus cannot be exceeded by a Laminate. I have tried the STACK Option in the Laminate creation tool but this did not seem to help. Any help would be greatly apprechiated! Greetings, Lenny
  7. Hello Community, I have come across another small problem and I am here yet again to ask for help. I want to optimize a part which has a load applied to it using a bolt, and is connected to 10 single screws, which I modelled as SPC. Now, in my optimisation, I would like to assign a minimum share of the applied force that each SPC will have to endure. (e.g. I apply a force of 30000N to the part and the maximum force per bolt is 600N. The SPC force should be applied so that this maximum force is not exceeded. In the SPC Card I can apply values to the 6 DOFs, however I am not sure if this is what I need. Any help is greatly apprechiated.
  8. Perfect, exactly what I needed. Thank you so much!
  9. Hello, Thanks, this seems to work! I have been playing with the FREEZE contacts all morning to understand their behaviour. Does the FREEZE contact only transfer loads from master to slave and not back? I don't quite yet understand how contacts work.
  10. Wow! This is exactly what I was looking for! if you don't mind me asking, how did you manage to make the 0° ply direction go in a circular manner? I can only get it to point into one global direction (x,y,z), but having the ply/material direction go in circles around the part should come quite handy! Your support is amazing, thank you so much.
  11. Oh my god yes, this is exactly what I expect the result to be! Would you mind sharing with me how exactly you achieved this? Thank you so so much!
  12. Dear community, another question from an Optistruct beginner! Let's say I have 3 square surface directly above each other with a distance of about 10mm. Each surface is inidivudually 2D meshed. Now I apply two forces, one to the top surface, one to the bottom surface, both parallel but opposing each other. It basically looks like this: <---- ------------------------------ ------------------------------ ------------------------------ ----> Imagine as if it was a composite part and each surface respresents one ply. I would like to transfer these loads through these plies. (I am aware that I am missing an SPC and that there are easier ways of representing composite parts) Not to the question: How can I "connect" the elements one by one to the elements of the next upper surface so that loads will be transferred? I tried using RBE2 und using two faces, but two problems arise: 1. I cannot analyse the part anymore (Error codes that Google wont give me an answer for) 2. The resulting connection looks like a spider-web, so the loads would be transferred to the wrong elements of the adjacent surface. Any help would be greatly appreciated. Regards, Lenny
  13. This is exactly what I am looking for. I used multiple plies with steps of 5°, to get a more accurate result, but this should work just as fine. The optimum result of the fibre orientation optimisation should be forming a "ring" within the circular part, which, in reality, is the ideal fibre positioning. However as mentioned, I am unsure how to achieve the expected optimum result. I am unsure if Optistruct is able to compute this case with realistic results.
  14. Hello, If you don't mind me asking, have you come to a conclusion?
  15. No, the force is parallel to the ply surface, thus the force will only deform the ring and not bend it. The surface part (ring) and the force are parallel to each other in on plane. Thank you for your effort!
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