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Turbokraken

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  1. Dear PrasannaK, Thanks a lot for that, it worked! I have created a contactsurf with the 3D solids and then "free edges" option and connected that to the surface of the other component with the appropriate search distance. Thank you!
  2. Hi Q.Nguyen-Dai, Good point, creating a local CS may be necessary, or rather very probably necessary. But it was just a general idea that I stated, the exact procedure needs to be figured out by mrtimwinkler. Lets hope he is successful in generating a sensible script.
  3. Hi Timo, 1. The syntax for the dequations should be presented in the HyperWorks documentation. Make sure to always call the responses you are using in the beginning, like you did: f(x,y) There are some other function such as "ABS()" which creates positive values, for example. It should all be in the HyperWorks Help data. For your question regarding the power, the right way to do it is using "**", like a double-multiply. f(x,y) = sqrt(x**2+y**2) I am unsure if sqrt() is a valid command, but I suspect it is. Otherwise just use **0.5 2. In the card for the response you can define a response list and define "optiresponses". Those have to be the ones you are calling in the DEQ. However I am pretty sure the names of the responses and how you call them in the DEQ have to be the same. (Be wary, some characters do not work and confuse the DEQ, such as "_".) Simply click on your function response in the model browser and edit the Response List. 3. I have no idea, I am sorry. I hope this was helpful in some ways. Best Regards, Lennart
  4. Hello mrtimwinkler, I am by no means an expert on this, but I have dealt with a roughly similar issue in the past and my suggestion for you would be to look into the HyperWorks scripting language tk/tcl. You can find plenty of tutorials online and the HyperWorks help documentation is full of all the available commands. It is quite powerful to help you in modelling special tasks, so well worth to learn. You can automate a lot of these tasks which would be tedious to do by hand. A script is even more handy if you have to model the same model multiple times. For starters, have a look into tk/tcl programming language to understand the syntax. Next, check you "command" file in the HyperWorks working directory. This file is tracking all the things you do in HyperWorks and translates them to tk/tcl. This makes it easy to check how a command, e.g. constraint creation works. This is currently the only way I see to do this properly without doing it all manually. Perhaps this might be a sensible logic: 1. Pick the nodes where constraints are supposed to be, all on a line 2. Go through each node individually, check its coordinates 3. Find the nearest two nodes (which are the next ones on the line then) and check its coordinates 4. Create a vector from the two neighbour nodes 5. Create Normal direction from vector within plane (this might cause an issue, because you need more information to properly define this one.) 6. Create constraint by normal direction vector and current node. I hope this is at least kind of helping. Best Regards, Lennart
  5. Hello Everyone, I hope everyone is doing well. I have come yet again with another quick question: I need to transfer loads between two geometries, which are meshed with shell elements and are perpendicular to one another. It looks like this: They also have different element sizes and the line geometry of the left one cannot be properly projected onto the right one. Also, there is a gap of 10mm between them. I decided to go for a TIE contact with contact surfaces, but somehow this configuration does not transfer loads at all or tie my parts together. I suspect it is because the contact surfaces are perpendicular? I have tried setting the search distance of the TIE much higher than the gap length, yet to no avail. Seam Connector is also not working for me, I just cannot get them to be realized. - Can I somehow improve the modelling so that I may use contact surfaces for TIEing my parts? - How would you try to connect these parts given the circumstances? Any help would be fantastic! Thanks in Advance and best Regards, Lennart
  6. Hello Everyone, I cannot seem to get the adhesive modelling to work. I have two simple geometries that I would like to join with an adhesive, which I would like to assign material properties to. The way I tried doing this is via the Connectors-Panel and I wanted to create an adhesive with hexa/brick elements, so I can assign material properties and get stresses in the adhesive. However I can never realize the conenctor. This is what I did: 3D -> Connectors -> Area Location: Pick the surface of one of the meshed solids Connect What: Pick the other whole meshed solid component type = adhesives Shell Gap, Quads = 10, Layers = 1 This is working so far, there is a yellow planar mesh appearing. But realization is never working, there is always the message: 0 projections could be made for the test points. Apparently there is an underlying misunderstanding on how to go about creating a brick adhesive. I have looked into the Connector Tutorial, but it did not help me understand to get to a brick adhesive. Could anyone assist me with the correct way of connecting two meshed solid with an adhesive material? (Would it be an alternative to simply create a solid to act as the adhesive and TIE it to the surfaces?) Best Regards, Lennart
  7. Just a quick update: I have recreated the model in 2D, so without the shell elements. It now consists of only one half of the bridge and only lines. Lines are again a PROD, the roadway is a PBEAM. Unfortunately, the exact same error message appears. I have used the MECHCHECK function to check for any rigid body entities. This is the Y-displacement (Down-direction). So apparently, the ROD-elements displace in an irregular manner. This is, as suggested by the error message, a sign of insufficient constraints. What I did then was to constrain all nodes of the main and suspension cables in DOF1, DOF3, DOF4 and DOF5. Consequently, the RODs can not only move in Y-direction and rotate around Z-axis, which will cause displacement in Y-direction. And miraculously, the model is working now! (I still have a modelling error that you can see in blue, but the principle is working. So, having multiple ROD-elements seem to require more constraints than I was used to. Thank you all for your input, this problem is solved. Best Regards, Lennart
  8. Hi Q.Nguyen-Dai, I thought so too, because in reality the roadway would have to connect to an actual street somewhere. Unfortunately though the task was defined this way, with only the two upper constraints on the main cable. As far as my understanding goes, the bridge would be well enough constrained even without those additional constraints. I have just incorporated that change into the model, but it did not change the error message. Thank you a lot for opening the file and having a look. Any further ideas, maybe?
  9. Hi PrasannaK, Thank you for your answer. I performed the check as you suggested but not a single element has failed the test. "0 free ends were found on 0 1-D elements", no free 1-d's either or rigid loops. All appears to be fine. Dou you perhaps have any further ideas? Best Regards, Lennart
  10. Hello Everyone, I am struggling with quite a simple question today and I hope that maybe someone of you could perhaps check my model to see what the issue is. For a university project I am currently writing a FE-script which shall calculate the displacement of a suspension bridge. Natually, I want to validate my work. For this I am using the HyperWorks Student Edition to build a very simple model of said bridge, with only lines and shells. The bridge I modelled before had a PSHELL for its roadway and PBEAM for its main and suspension cables. This worked fine, but I thought displacement might be more accurately modelled by using ROD-Elements. However when I replaced the Line Elements, I keep getting the following error message when running OptiStruct: *** ERROR # 153 *** Exactly zero pivoting encountered during Numerical Factorization; the model may have rigid body mode. Solver error no. = -514 spc set id = 1 index = 1 Possible reasons are: 1) insufficiently constrained model, 2) having rigid body mechanisms within the model, 3) extremely ill-conditioned rigid element sets, 4) extremely thin shells (as used for skinning) that have MID2/MID3, 5) gap elements with extremely high stiffness (KA, especially KT or MU). 6) extremely high Poisson's ratio in hyperelasticity material definition. Check the model and rerun the problem. (MECHCHECK may be used to find the rigid body modes. To do so, change the input to be an eigenvalue analysis and add MECHCHECK.) (WARNING: results obtained with MECHCHECK cannot be used because the model is changed internally.) This error was detected in subroutine bcsmtxfct. And to be honest, I really do not understand much of what is suggested there. I have attached the very simple model, it would be fantastic if someone could have a quick look at it and tell me how to make it work. Thank you already in advance, this community has helped me time and again. Best Regards, Lennart BridgeValidationShellRodV1.hm
  11. Hi All, I have a modelling question regarding Forces. I would like to assign a force magnitude based on an equation. There is a neat option available within the Forces window itself, but I need to incorporate some variables from my model, e.g. the mass of the model. (I am not trying to model acceleration forces, so GRAV card is not an option here). The question is how can I incorporate a changing force into my optimization model? I will need to declare variables somehow, of course. Which type of variable can be used within this equation? Can I simply pop in a "response"-name like I can with dequations? Any advice would be fantastic. Best Regards, Lennart
  12. Dear tinh, I have tried several formats now, but to no avail, unfortunately. Still only the surfaces are imported. With autocleanup or solid create by boundary I cannot recreate the original geometry.
  13. Dear All, I have faced a weird issue that I cannot seem to resolve on my own. It is actually rather simple: I have a .CATPart in CATIA which is a rather complex solid. It is also declared to be a solid in CATIA. Now, when I import it into HyperMesh, all I get is the surfaces of this solid, but not the solid itself. I cannot sensibly perform an autocleanup and then create a solid by boundaries, because it is not finding the correct shape as it is supposed to be. Is there an option that I missed or a setting which causes the solid to be disassembled into surfaces? Or do you think it is more probable that my original solid if faulty? I unfortunately cannot shape the data as it is classified. Has anyone perhaps faced a similar issue? Best Regards, Lennart
  14. Hello, You're right, I kind of expected this... I had just hoped I was doing some more obvious mistake. I had been searching in this forum and for this importing of loads someone had uploaded 2 files as tutorial where I could learn how it works. Unfortunately they were not available anymore. Is some sort of tutorial available for importing pressures from a .csv? That would really help me understanding my mistakes. Thanks you your help. Best Regards, Lennart
  15. Dear All, I am currently modelling a wing-like structure which generates lift and is of course loaded by a aerodynamic pressure. I have received a list of aerodynamic loads from pressure and suction side, which I transformed into my models coordinate system. My table looks something like this: -85 76 405 1,2 -82 77 410 1,3 -81 77 414 1,4 -81 78 418 1,5 -80 79 422 1,6 I have X,Y,Z coordinates as well as magnitude and its fitting quite well with my geometry, albeit not perfectly. Now if I apply this pressure using linear interpolation to my whole wing, its working fine. However I only need those pressures on one side, which is why I am only selecting the lower face. When I click "create" its calculating and then giving me the message "No pressures were created" without telling me why. Upper side is also not working. Furthermore, when I am looking at the pressure created with the full wing, all pressures have the exact same magnitude, which kind of diminishes the point of importing pressure loads. Have I completely misunderstood the input data I need or is there something else going on? unfortunately the model is classified and I cannot share it, but I hope someone of you knows what has been going on. Thank you for reading this far and best regards, Lennart
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