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  1. 2 likes
    Hello @BG913 I guess "hm_gettiedentities" is you are looking for. Ex: *createmark nodes 1 248; hm_gettiedentities nodes elems 1 2; hm_getmark elems 2; Thanks, Imoto
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    Sorry Mario, i should have been clearer. Blend = Loft with at least tangent continuity (may or may not be curvature). So essentially using loft you can blend two edges and apply required continuity with greater control. loft.mp4
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    Hi, the optimization problem is not well-posed: the weight is constrained to be the same as the initial weight. Laminate thickness can not increase in free-size optimization. Therefore the optimization result is the same as the initial configuration. Try lower mass constraint than the initial mass or use volume/mass fraction constraint. The 3.6 mm thickness is actually the result of the 1st iteration that starts with 0.6 material fraction by default with mass constraint . CompositeOptimization2-edit.hm CompositeOptimization2-edit.fem
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    Hi Paulo, I dont think so that's the problem your space in your system is more than sufficient to run this model. When something comes like this next time, just restart the software and reassign the boundary conditions for your model.
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    Glad to help. The topology stress constraint acts as a global stress control. It will filter out only the artificial local stresses caused by point loading or boundary conditions so artificial stresses will not be removed. Refer to Topology Optimization of a Hook with Stress Constraints. Those stress concentrations can be removed in the subsequent design fine-tuning stage such as size, shape and free shape optimization with DRESP1 stress constraint. The artificial stress concentrations are stress singularities due to a point load or constraint, sharp re-entrant corners, corners of bodies in contact,... For more information refer to: http://www.acin.net/2015/06/02/stress-singularities-stress-concentrations-and-mesh-convergence/ https://www.comsol.com/blogs/singularities-in-finite-element-models-dealing-with-red-spots/ https://www.digitalengineering247.com/article/dealing-stress-concentrations-singularities
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    Let me add another approach that I've just learned. There are many options to perform it but I’ve found this method very simple, flexible and self-explanatory. Summary: In the example, watertank.oml is the master file. It: changes the input parameters (controller gains) runs (repeatedly) the file Watertank_parm.scm (slave) collects results doing post-processing (plot) at the end. I’ve created a quick video to summarize how to run the demo. Present working directory must be where you save the files (the video shows how to select the pwd). Otherwise use an absolute path in the oml file. Liv ParameterSweeping.mp4 watertank.oml watertank_param.scm
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    Hi, check the units used for added masses. Their magnitudes are consistent with kg, not with tonnes which are units used for material laws. Therefore the weight of the added masses is 1000x too high.
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    I prefer Utility>Radioss Tools>RBODY manager where all rigid elements are listed with their related master nodes. There are other ways to get master node ID:
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    Hi, I think the file has initial intersection. Contact can only create penetration. Intersection is a CAD or FE issue. Check the intersections in Hypermesh using Tool > Penetration. This way it displays the intersections and penetrations part wise. I found 19 intersections in your model as shown in the attached image (displayed in white colour on grey elements). You need to merge the nodes at highlighted location. Or, move the elements away so that there isn't any intersection.
  10. 1 like
    Hi, Stress constraint is not recommended in the design concept stage: topology, topography and free-size optimization.  The stress constraint definition in a topology optimization is a global constraint and does not target local stress concentrations. These areas can be addressed subsequently through size, shape, and free shape optimization or a combination thereof. Artificial stress concentrations are filtered out during topology optimization with stress constraints. These include regions around rigid connections, concentrations due to hard geometric features such as corners, etc. Stress constraints for a partial domain of the structure are not allowed because they often create an ill-posed optimization problem since the elimination of the partial domain would remove all stress constraints. Consequently, global stress constraint applies to the entire model when active, including both design and non-design regions. Stress constraints may not work well in a model where there is a large differential in response values between design and non-design spaces. In these cases, it is recommended to modify the problem formulation to say, compliance based for example. It is not recommended to use the global stress constraint along with a mass/volume constraint. The constrained mass/volume may not allow the stress constraint to be satisfied. DRESP1-card stress constraint is used in subsequent design fine-tuning stage such as size, shape and free shape optimization.
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    Hi Alessio, Currently, SimSolid only supports static stiffness for bushing elements. Output of velocity.acceleration will be available in our next release. Girish
  13. 1 like
    Yes, they are Torques. They are resolved in the reference frame used when you created the Output to report that force. It will default to Global if you didn't create a reference frame
  14. 1 like
    Hello Berke, Please, find attached a pdf which explains clearly the differences between Bertotti and LS methods and how to take advantage of them in Altair Flux. The reason why you cannot use the first two time steps to calculate iron losses is that it uses derivatives and to obtain the derivative in point N you need the variable values in previous points (N-1 and N-2). Best regards, Alejandro Iron_losses-Altair_Flux-Bertotti_LS_models.pdf
  15. 1 like
    Hi Paulo, I was able to do the simulation in 2019.3, I guess this is the Alavanca Stilo file_13 ( regarding HPDC ),( Kindly correct me if I am wrong) I am sharing the file with you Alavanca Stilo_13.icast Desculpe pela resposta tardia, pois estou em viagem. Alavanca_Stilo_13.icast
  16. 1 like
    Hello Rahul, thanks a lot for this quick reply! Ok, so I'll just use ALPHA1 and ALPHA2 then. Cheers, cfuser
  17. 1 like
    Damping This Nonlinear Transient solution sequence currently only provides support for Rayleigh Damping. The damping parameters can be input using PARAM, ALPHA1 and PARAM, ALPHA2. Subcase-dependent parameters can be input using the Alpha and Beta fields on the TSTEP Bulk Data Entry. Use of G, W3, W4 is mainly for linear dynamic analysis.
  18. 1 like
    Hi, open the run_name.mvw session file in the run directory. Alternatively, open the run_name_s1.h3d file which contains only stress and displacement data. Note that by default only the first and last optimization iteration results are output by default. All iterations can be output with Analysis>control cards>Results>toggle RES_VI to ALL.
  19. 1 like
    Hi, the initial kinetic energy is not enough to deform the crashbox. The impactor weighs 0.6 kg which is far less than the 100 kg structure so the impactor simply bounces off. Increase the kinetic energy by increasing mass, initial velocity or both. Negative energy error represents energy dissipated from the system and this can be from many sources like plastic deformation, hourglass energy, contact with friction, damping,... Review the energy balance to identify the source of this error.
  20. 1 like
    Please make sure to keep the unit consistent. Refer the below post where we shared best practices for random response analysis. https://forum.altair.com/topic/30038-psd-analysis/ Some Tips for results comparison with other solver • Use “Amplitude” in MATFAT (default is “range” in OS) • Request for “Damage” results on elements in other solvers • Define right option for PSD input for random vibration fatigue (Log vs linear) Attached Random Fatigue deck for your reference. Note: OptiStruct supports Random Fatigue Analysis only Uniaxial SN with Von-Mises stress and approximated principal stress RandomFatigue.fem
  21. 1 like
    Perhaps, some nastran mats and props not supported in dyna will be deleted. Or it's maybe a bug!
  22. 1 like
    Hello, the results on prediction planes can be exported to the ASCII line format via File => Export => Export Data (Planes), such ASCII files can be visualized in other software tools. In ProMan the results on (arbitrary oriented) prediction planes are only shown in the 3D view, here you can define by zooming etc. a nice view so that the prediction plane is fully visible and then save this view using the "Store" button on the upper right. For the next result (e.g. after having changed the project settings and rerun the simulation) you can then switch to the same view from the "Camera" drop down list in the upper right. Furthermore you can use the button "Save View to Image" to save the picture as .bmp, .jpg, or .png. All these buttons are only shown in the 3D view.
  23. 1 like
    ... model and video are attached. impulsiveForce_IM.mp4 2_simplified_SingleBC_Impulse_2019.3.stmod
  24. 1 like
    You could refer to below tutorial from online help: NVH-1100: NVH Director Assembly
  25. 1 like
    Hello, the WinProp results are generally deterministic and consider the defined environment, so the results are also reproducible, i.e. if you run the simulation twice you will get two times the same results. The radio channel is generally subject to slow and fast fading. The slow fading represents the average signal levels, e.g. if you are behing a wall you get on average a lower signal level because of the shadowing due to the wall. The fast fading represents the "random" fluctuations due to changes of the phases for the individual propagation paths (rays) which are then either superposed contstructively or destructively at the receiver antenna. The fast fading can be reproduced in WinProp by using the standard ray tracing and activate the coherent superposition under the ray tracing settings. Then you will see the "random" fluctutaions of the signal level over short distances. Nevertheless also in this case the results are reproducible, but you might change the transmitter position slightly or analyze the signal levels at different receiver positions to see the fast fading and the random impact.
  26. 1 like
    This solved my issue. Many thanks! Was there a bug in previous versions?
  27. 1 like
    Yes, see "Automatic Meshing for Regions" in the Altair_Feko_User_Guide.pdf
  28. 1 like
    Hi, -you have created rigid with the master node on a structural element- this is not allowed. Make sure you use the "calculate node" or pick a free node (not connected to other elements) as independent node when creating rigid elements. Set Icog=3 or 4 so the master node will not be moved to CG -check unit consistency: the material properties are in tonne, mm, s so the gravity should be 9810. Also, define appropriate units in the begin card -gravity was acting in the wrong direction, so a negative scale factor was applied to reverse the direction -the boundary condition on the tilted platform constrained 1236 DOF. It should constrain 12345 instead -the contact sets between wheels and tilting platform were swapped -advanced mass scaling AMS is used instead of DT/NODA/CST mass scaling -the run time was extended to allow the bus to hit the ground -the floor is not large enough: rigid wall can be used as ground instead simple_bus_7_edited.hm
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  30. 1 like
    Not at this time. Today, SimSolid only reports the final fully stressed state.
  31. 1 like
    I forgot ! for the model you can start from the page 167
  32. 1 like
    Hey There a good book provided by Altair. Inc. You can find the basic of what you're doing. You can find as well the model described in details ... Cheers, Introduction_to_Nonlinear_Finite_Element_Analysis_using_Optistruct-Altair_University_(2018).pdf
  33. 1 like
    This model is from OptiStruct Example Guide. Bumper_OS_Impact.fem
  34. 1 like
    Hi Rajath, Embed can import a Simulink model that is saved in .MDL format but there is no easy way to import an Activate model into Embed at this time. Ric
  35. 1 like
    Great Sourav. Thank you for the suggestion! Surely the content will help a lot, I'll right now to donwload and read. Regards,
  36. 1 like
    I think the values are practical values, but I don't have a reference. I picked up the values from somebody else's example (presented publicly) and I have used it a few times myself in public examples. It would be wise for you to do an on-line search or literature search for typical values, but if the application is not critical, then these are good values to start with.
  37. 1 like
    In ProMan, under one of the tabs of Project / Edit Project Parameter, you define a prediction plane: a horizontal rectangle at a certain height, by default at z=1.5 m. So you don't need to do anything special in WallMan. To create an additional non-standard prediction plane in WallMan, see the answer at topic 36975:
  38. 1 like
    It works ! Thank you for everything Hyperman... See you for another issues... hmm...! Challenges ! Pegase33
  39. 1 like
    I have a similar problem as @ep2398 experienced. I converted Radioss A001 result files into h3d file utilizing HVtrans. In Hyperlife, different kind of stress results are available in time series and result can be seen in Transient Response as subcase. However fatigue analysis results are stiil receive as N/A for both damage and life. Why fatigue analyses can not solve the problem, though explicit analysis is performed time-dependent event with time dependent loads?
  40. 1 like
    Hi I am trying to learn TPA analysis in NVH Kindly someone help with reference deck and document about background process and post processing Thanks in advance Regards Sai Vignesh
  41. 1 like
    HyperViewで流線表示ができることをご存知ないという方も多くいらっしゃるかも知れません。 Sereamlines機能を使うと、流線を書くことができます。 単純にベクトルで表示するよりも判りやすいかと思いますので、ぜひご活用下さい。 HV_Streamlines.mp4
  42. 1 like
    Hi Mohamed You should be using the numerical green's function (NGF). Have a look at the "H.4 Optimise Waveguide Pin Feed Location" model in the Examples Guide.
  43. 1 like
    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!
  44. 1 like
    Please refer the attached files from OptiStruct online help. https://altairuniversity.com/learning-library/reducing-floor-vibrations-at-driver-seat-locations-of-body-in-white/ TPA.fem Transfer Path Analysis.pdf
  45. 1 like
    CAEエンジニアが覚えておいた方が便利なエクセル関数の1つに、「VLOOKUP」関数が挙げられると思います。 結果値リストから、いくつかのIDのみの結果を取得したいときに便利なのが「VLOOKUP」です。 例えば、HyperViewのQuery機能で全ての節点IDを取得しておき、後から指定したいくつかの節点IDの結果を取得するといった事が簡単にできます。 VLOOKUP関数では、(検索値、範囲、列番号、検索方法)といった引数を指定します。一般的な関数ですので、専門的な内容はGoogle等で「VLOOKUP」で検索してみて下さい。 サンプルの.xlsxファイルを添付しておきます。 VLOOKUP.xlsx ※ファイルのダウンロードには、当フォーラムへのSign up(ユーザー登録)およびSign in(サインイン)が必要です。 VLOOKUP.xlsx
  46. 1 like
    You can refer the model shared in below post. https://forum.altair.com/topic/30505-how-to-apply-simulatenouly-xy-and-z-excitation-load-in-optistruct/ So, you define the excitation (SPCD / Force) in the FRF step. For example if you want to apply SPCD in X, Y and Z directions, you will have 1. 3 number of Subcases with 3 DLOAD 2. 3 RLOAD cards corresponding to DLOADs 3. 3 SPCD cards 4. one or more TABLED1 card Now, the loading will be applied in FRF step and the results are outputted for those loads. When it comes to Random part, you need to define Random Input for all 3 direction using same ID. 'All RANDPS entry with same ID will be added together'. RANDPS,101, 11, 11, 1.0, 0.0, 11 RANDPS,101, 12, 12, 1.0, 0.0, 12 RANDPS,101, 13, 13, 1.0, 0.0, 13 With 3 TABRND1 cards ( 11,12 and 13) The additive results of Random are then multiplied to the FRF results to get PSD / RMS outputs. Hja and Hjb are the results from FRF and Sab from Random (PSD) Please refer attached to pdf for the two scenarios based on Random input. Random Input.pdf
  47. 1 like
    「Process Manager」で利用するタスクや、操作パネルを作成するには、「Process Studio」を利用します。 Windowsのスタート⇒プログラム⇒Altair HyperWorks⇒Tools⇒Process Studioから起動することができます。 Process Studioでは、以下のビデオのようにタスク(プロセス)の追加や、各タスクで用いる操作パネルの作成ができます。 ProcessStudio-Add.mp4
  48. 1 like
    Hi Nachiket Kadu I think by this way also we can find it out. Try this too Click Card edit > Select rigids > edit
  49. 1 like
    Hi @all First, i hope this is the right forum for this topic. If it isn't, please switch. I've to simulate an multiphysics coupled heat transfer + fluid cooling process (like cooling fins or spines). For that case i've to define an heat flux into the base of the solid structure. The heat is flowing through the structure and left the structure on the "water" cooled contact surface. This cause an increase of the fluid temperatur deltaT (T_in-T_out) on the outflow against to teh inflow temperature. The fluid flow is perpendicular to the heat conduction in the solid. Points I've finished: Import complex geometry into ACUCONSOLE (+meshing) Define the global problem description Define the inflow, outflow, heat source (basic BC's) Simulation of the fluid flow through the structure still open Points: Simulation of the heat conduction Define the result of the Simulation (heat cond.) as boundary for the flow simulation As i wrote in the title, at the moment I work with the ACUCONSOLE. Is Hypermesh (with the ACUsolve deck) better for multiphysics like this? How can I define old results as boundary conditions in new simulations? (current temperature/heat flux as input value for the fluid wall) Is it possible to import more than one geometry into acuconsole? (The software always want to delete the previous part when i import a second one) I hope you can help me to solve this problem. best regards Alex
  50. 1 like
    Use MATHE card.PFA screenshot for same.
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