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  1. 2 likes
    Hi Thanks for the response. I worked it out. I ended up using the dummy bodies. I was thinking about it in the shower after I posted the question, and thought of "piggybacking" the bodies and joints to each other. tried the next morning and it worked
  2. 2 likes
    a couple more images from the result. I've started from a 10mm regular mesh, and i've selected the elements to be refined. I've remeshed to 5mm target, and kept 2 layers for transition and 'inside' disabled, so that the selected region was remeshed to 5mm and the transition was kept outside. taking 2 adjacent layers.
  3. 2 likes
    I believe he means above 4 core's no considerable performance increase was found..just like convergence study. So for this application don't waste resources as it will not leverage more tham 4 core's.
  4. 1 like
    can you explain a little better what is going on with your model? what did you try? did an error occured? i've noticed that you're running FRF direct in your model. This is very expensive. I would use FRF modal instead. For this I would change the EIGRL lower bound for frequency back to zero.
  5. 1 like
    Not really.. In an analysis stand point, yes, you can obtain both frequency and amplitude from the frf curves. But regarding optimization, frequency is only got from modal analysis loadstep, as a response. The frf amplitude will be extracted from the frf loadstep.
  6. 1 like
    Can you be more specific? What kind of angle? A geometric angle in your part, such as your honeycomb? If is this you can create some shape design variables using HyperMorph. This is shown in some of the tutorials for OptiStruct i believe.
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    Did you know that there are dozens of interesting examples accessible online for multi-body / motion simulation using Altair software?! See https://altairhyperworks.com/motionsolve-models/ These examples have been designed to help raise your awareness for the kinds of simulations that are possible with Altair's multi-body motion simulation tools. There are currently 17 examples for MotionView+MotionSolve and 29 examples for Inspire Motion -- with dozens more examples scheduled to be added quite soon. The goal is to continually add more and more over time. So consider bookmarking that page and check back often! Each example comprises two pieces: (1) a movie clip that plays automatically in your browser + (2) a downloadable zip file which typically contains: One or more movie (.mp4) files. Pre-built model files for the complete, mechanized multi-body system. Results files. A presentation (.pptx) file describing the model and how to use it. Enjoy!
  8. 1 like
    Hi In order to perform your optimization, you will need to create your responses. You can create one response using a dequation, which is the transmissibility, the same way as you did in your graph, but now you will embed this into your optimization model, and then refer this as a constraint and assign a value of 0.1 foe your 100hz. Just take care and remember that as you change your structure, your mode frequency will change a bit, and maybe the frequency of interest might change as well.
  9. 1 like
    By the way, if the vibration mode is well known you might not need to run the frf for the peak frequency, only modal (response: frequency)
  10. 1 like
    You could calculate your transmissibility by using advanced dresp2 or dresp3 with Compose. Dresp2 allows you to create an equation and use this as objective or constraints. Take a look at OptiStruct help for more details. As for the model you can zip the fem file. It would get smaller. But i don't have access to my computer now. Sorry.
  11. 1 like
    Correct. In the browser you're highlighting, you can enable only for tour loadstep of interest: output>>displacement, format op2. Delete any other output/global output cards.
  12. 1 like
    Hi, Instead of requesting global output results, you could request op2 format only for loadstep 2. In the model browser ckick in the loadstep2 and under outputs select the desired output and choose op2.
  13. 1 like
    It may be that the OP2 file for Eigenmode Manager can only contain output from the modal analysis subcase - so maybe make sure there is no output requested for the linear static subcase.
  14. 1 like
    i believe this is a convergence issue related to your TMANUF value in your plies. As you have a 0.25 TMANUF for most of the plies, the optimization problem becomes a discrete size optimization, and as usual, discrete optimizations are harder to converge. In your case the optimizer has to make a decision only between 0.0 and 0.25. This is because TMANUF forces it to give steos by 0.25 only. I dont understand why it takes all your variables to 0.0, but i assume that once it gets to 0.0 it gets stucked there, and because it is a dicrete optimization it can't get out. Try changing a little the TMANUF if possible. Anywya, another thing about composites, try to imposed a balanced laminate and symmetric as these will avoid undesired couplings (ABD matrices). In the first step, of free-size, have you used SMEAR option for the laminate? SMEAR ignores stacking sequence and takes an averaged behavior.
  15. 1 like
    In OptiStruct you can use psolid and assign a material with air properties. For RADIOSS you have more options, including material hydro. You could use SPH to model the particles for example. There are a few examples in the documentation of RD using sph or ALE.
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    Use set nodelist [hm_entitylist node] It runs faster than *createmark and hm_getmark
  18. 1 like
    So 1D element (shaft) is perpendicular to 2D shell ?
  19. 1 like
    I'm sorry. Im away from the computer, ao i couldn't run your model. Did you look at your nl.h3d file? Is there anything unusual there? Try changing the NLADAPT load collector and increasing the NCUTS to at least 10. It controls the.number of maximum cutbacks. Default is 5. Try increasing to 10 or 20.
  20. 1 like
    You can create your desvars as described before, and for responses tou can create 'frf acceleration'. Just take care when using a frf responses as you need to think well if this would be an objective or design constraint. As you will have a vector (amp x freq) you need to correctly define this, if you want a specific frequency, or a maximum value, etc..
  21. 1 like
    With small size analysis, you can do some calculations with different element size for convergence. But keep in mind that in real industrial situation, you can not do this kind of convergence analysis, because of budget limitation. In this case, your experiences play an very important role.
  22. 1 like
    We usually perform a convergence analysis to decide how small should be the element size to capture well the behavior of your structure, but not using "infinite" elements. I would say you need t mesh your model according to what you want to capture.. don't "overmesh" with no necessity. I believe this separates an simple user from a real engineer.
  23. 1 like
    seems like your surface edges there are supressed. Did you use 'toggle' in this edge? Or sometimes according to your geometry dimensions (meters, mm) while importing, HM can perform some geometry cleanup based on some tolerances. Check your import options, also.
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    maybe i'm not understanding you correctly, but to me, the RP will be just a regular node in HM (geom>>nodes) that is "flying" at some coordinates and is not attached to any element. Then, you will use this node as a 'independet' node in the RBE2, and its dependent nodes will be attached to your solid. So your "flying node" will be your RP. Is that what you need?
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  27. 1 like
    Hi Uri, We did some study,it uses max core as it is available in the machine, but it default we set it for 4 cores, performance will increases up to 6 cores, and I guess beyond it remain same. Regards Sourav
  28. 1 like
    Hello Sai It is possible to customize. There are various levels of customization possible. a) Create a wizard library, similar to what is available as the vehicle library under Assembly wizard. You would have to save various sub-assemblies as system definition if there are many and create tasks or events and use the task wizard b) a more complex but one that provides much more flexibility is to customize using the TCL API But to accomplish what you have described above, there is a much simpler way without the need for any customization. Here again there are 2 ways 1) Use the Data Summary to modify the CG, Inertia and Motions. One at a time run the model through the run panel with different names for different set of data 2) You can connect the MotionVIew model to HyperStudy -> define CG, inertia etc. as parameters (design variables), set up a DOE study and submit to Hyperstudy. Hyperstudy will modify the model and solve in loop and provide results for each iteration. I recommend tutorial MV-3000 & MV-3010 to learn about using MotionView in combination of Hyperstudy for DOE and optimization. Regards praful
  29. 1 like
    Please try to describe a with a little more details the difficulties you've found. I believe you're using HW2020 and you're following some tutorial for FRF Modal. In 2020 the TABLED1 was moved to a different entity called 'curve'. Instead of creating a load collector, create a curve in the model browser, add a new curve and then enter your points.
  30. 1 like
    By definition, a SHELL element does not have TWO faces! So you have to work with SOLID element.
  31. 1 like
    [winfo children .model._pw._fbr.content.frmTreeArea.frmTree.__treectrl.popupMenumain] invoke "Cross Section" This one is working perfectly... Am i right? @tinh Regards, PD
  32. 1 like
    Widget path may be changed. You should dump its binding command to use
  33. 1 like
    Hi Elements in hypermesh have internal (hypermesh) id and solver id Solver id depends on user profile (solver) Internal id depends on how and when element is created If you renumber elements by panel 'renumber'=> you changed solver id But *createmark elems 1 49000 => indicates that select an element with internal id 49000 (which may not be existing) Pls check reference help if *createmark has any option to select "by solver id"
  34. 1 like
    for OptiStruct, usually RAM is the more important, as having enough memory would allow you to use in-core mode, wwhich runs faster. But of coarse a good SSD and a fast CPU helps. RAM >> larger models require more RAM memory to run efficiently SSD >> a good SSD will speed-up computations when large data blocks need to be used (this tends to be less important if enough RAM is available) CPU >> newer CPUs are more efficient. But number of core's are not so heavily important for OptiStruct. You can have a gain, but it also depends on how many licenses you have available and kind of model. Explicit codes tend to take more advantages. I agree with the above replies, and depending on how old ytour machine is maybe s better to replace it.
  35. 1 like
    i9 with 10 cores, and upto 6 cores the speed will increase, beyond 6 cores, the speed will remain same
  36. 1 like
    At first shot i9 looks better, specially if a good cooling system is used. Even if the original name looks like i7 specs has a higher clock, when you look into the details i9 specs might have a higher clock frequency if certain temperature thresholds are satisfed (and should be easier as it has less than 1/2 TDP). What makes me doubt is the memory bandwith, as the i7 has 4 channels (but at inferior speed) and i9 has 2 channels, and it is known that memory bandwith has plays a major role in CFD type simylations. I would say i9 is better, but I would not bet all my money on it. This does not take into consideration the processor cost at all.
  37. 1 like
    As Inspire Cast scaling is good for 4 cores, I would go for the the i7 with more frequency. As those 10 cores of i9 are unlikely to bring great benefit for Inspire Cast. Unless you want to run two jobs with 4 cores each.
  38. 1 like
    i believe this is being performed as a massa scaling to get a larger timestep (as the mesh will be reduced, density is increased to compasate for timestep reduction). Probably the problem is not so fast, and increasing a little bit the density allows a increase of timestep with no big losses on acuracy.
  39. 1 like
    I would avoid using the "default" wall approach and defining everything explicitly in HWCFD or HyperMesh. Also try visualizing in AcuFieldView as HyperView cannot handle all CFD results.
  40. 1 like
    Just to make everyone aware that these kind of multiple curve operation no longer needs MVPToolbar. They are available in the core product itself. Just select all your curves and RMB.
  41. 1 like
    actually, i've noticed that i was looking it upside down. Anyway, your upper plate has what total mass? I see a mass of 0.74Kg in your rigid body + the plate mass. What should it be?
  42. 1 like
    10% maximum difference for lower modes? it is not good, but not so bad, i would say. Your FEA model shows stiffer behavior, with frequencies consistently above the experimental results. If mass is correct, then, stiffness might be a little off. Sometimes material data is not 100%, or mabe the contact has induced a little more stiffness than desired. Another point, did you perform a mesh sensitivity analysis? probably refining your mesh would make it more flexible, thus frequencies would be closer.
  43. 1 like
    As you already have a rigid body in the lower plate, there's no need to use a material with so high Young's modulus. This could take to numerical singularities. Your constraints look strange to me, as your model is only constrained in X direction in the upper plate. As you use EIGRL V1 - 1.0, you will not see any rigid body modes, but they're there, meaning your model is not constrained. I've changed a little bit your contact definition and some material properties. But you should investigate further your boundary conditions. They should reflect what you have in your test. I assume the lower plate is the concrete base, and if so, it should be grounded. (create a SPC at the reference node of the rigid body) honeycom_displacement2.zip
  44. 1 like
    for clamping you should just use SPCs at the base of your honeycomb. For all the connections between honeycomb and Jigs you could use TIE/FREEZE contact to bound parts together, and reduce computational cost, as you wouldn't need so finer mesh for the Jig. Dynamic problems, are affeted by mass and stiffness. If your masses are ok, then probably your stiffness and connections are not so good, or material properties are not correct. You need to compare first expected frequencies against numeric ones. That's all I can say to you. Maybe others can help you better.
  45. 1 like
    Quick Trouble shooting HW malfunctions - deleting settings files
  46. 1 like
    Hi Find below the Radioss Full car model. This is a public model. Regards Prashanth A.R TAURUS_A00_0001.zip
  47. 1 like
    I use both Python(for Simlab customization) and TCL(for HyperMesh). In my opinion, Python is helpful for data management with OOP (of course it will be faster) and the syntax is easier than TCL. However, HyperMesh have supported many TCL API to interact with HM. We can use a lot of those API functions easily, no need to create our code again. This helps create script very quickly. Integrate Python in HyperMesh is easy but write a huge API functions need a lot of effort. I use Simlab Python but found many limitation because there are not so much API functions. I use Abaqus/Ansys Python but also found many limitation. So, Python or TCL does not matter. The important is supported API functions under CAE software. HW will support Python because they serve some trend. For me, I do not need. I need API more than Python.
  48. 1 like
    Hello, The R0 is defined in X direction & R90 in Y direction. Plz make sure your grain direction is along X axis. & draw direction should be Z.
  49. 1 like
    The big difference here stands on the specific functions HM uses, which are in a sense independent on the TCL language as it works as an additional package for the language. If you know the basics of programming and the syntax for TCL, I would suggest that you explore as much as you can the command.tcl file written by HM. This file is really useful as it records any action you do in the GUI into to a code format. Then looking at it, you can change the necessary arguments and others. To learn more about the available functions you can use with HM, please consult the "Scripts > Commands and Functions" part of the HM help. There you can understand the inputs for the HM functions and other capabilities you might be looking for. Hope this helps. Jefferson Vieira
  50. 1 like
    Hi, Select responses depending on model requirements. If you just want to reduce mass, select "compliance" as objective and "volume fraction" as constraint If your model has stiffness requirement => constraint "static disp" also If your model has eigen frequency requirement => constraint "frequency" also
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