• Announcements

    • Rahul Ponginan

      Please click here for a short but important announcement   03/26/17

      Dear Users Our Commercial and Academic users around the world can use these same forums here as before i.e. the Altair Support Forum , Commercial users from India with solver queries can go to the Solver Forum for India Commercial Users , Academic Users from India and AOC India Participants are requested to go to the Forum for India Academic Users and AOC India Participants , We will be tending to all queries in all the forums promptly as before, thank you for your understanding. 

Search the Community

Showing results for tags 'contact'.

More search options

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Content Type


  • Altair Support Forum
    • Welcome to Altair Support Forum
    • Installation and Licensing
    • Modeling (Preprocessing)
    • Analysis (Solvers)
    • Optimization and Design Exploration
    • Visualization (Postprocessing)
    • Model Based Development
    • Conceptual design and Industrial design
    • Manufacturing Simulation
    • CAE Process Automation
  • Academic Partner Alliance Forum
    • APA - Composites
    • APA - CFD & Thermal
    • APA - Vehicle Dynamics
    • APA - Manufacturing
    • APA - Crash and Safety
    • APA - Noise, Vibration and Harshness
    • APA - System Level Design
    • APA - Structural and Fatigue
  • Forum for India Academic Users and AOC India Participants
    • India EDU Installation FAQ
    • India EDU Modeling and Visualisation
    • India EDU Linear, Non-Linear Solver ( Implicit/Explicit)
    • India EDU Multi-Body Dynamics
    • India EDU CFD
    • India EDU Optimisation
    • India EDU Report Generation
  • Solver Forum for India Commercial Users
    • IND - OptiStruct for Linear & Non-Linear Implicit
    • IND - OptiStruct & HyperStudy for Optimisation
    • IND - RADIOSS for Impact Safety & Non-Linear Explicit Applications
    • IND - MotionSolve for Multi-Body Dynamics
    • IND - HyperWorks CFD forum
    • IND - FEKO, Winprop & Flux
  • Forum for our Australia and New Zealand Based Users
    • ANZ - HyperWorks
    • ANZ - Electromagnetics
    • ANZ - HPC (PBS)


There are no results to display.

Found 53 results

  1. I am trying to simulate an autofrettage process with the optistruct solver but i am not able to get any plausible results. In theory the process and simulation should be quite easy. We have two parts: a swage and a tube. The swage (which has a slightly bigger outer diameter than the tube) is pressed through the tube which results into contact with friction and plastic deformation in the tube. I meshed both the swage and the tube (only one quarter of each and conditions for symmetry to reduce the calculation time), defined all the boundary conditions like constraints and the load (forced displacement of the swage) but somehow the contact condition doesn't work at all. I read several tutorials and have tried different combinations of contact-surfaces or set-entities which were linked by a contact interface. I tried the preset contact types like slide/freeze/stick as well as a contact property with MU1/MU2 coefficients. When I use slide or freeze (images below) I get extremely high deformations and it looks like the points where the first contact occurs don't separate anymore, In addition to that I don't understand how they can already be in contact at that point since the contact should occur later when the bigger diameter hits the edge of the tube. Displacement scale factor is always set to 1.0. When I use the contact property (pcont) the calculation takes forever and I don't get any results (no convergence). I already tried to increase the number of iterations up to 50 and NINC up to 25. I would really appreciate any helpful advice or maybe someone with experience could check my model file. test_12.hm
  2. Hi, I am working on a laminate optimization. I'd like to do the three phases: Free Size Optimization, Size Optimization and Shuffle Optimization mentioned in the composite manual. My question is how can I connect the element faces in the 3rd direction with other elements of different components. In the attached picture I would like to connect the yellow part with the different laminate layers. Are there any solutions available, I could not find equal problems in the composite manual. thank you in advance, Martin
  3. Hello, I am trying to build a rigid mbd model with rigid bodies engaging in 2D rigid-to-rigid contact. I have defined curves where the contacts will occur, using the Add Curve functionality. Attached images 1.png, 2.png and 3.png from my curve panel, showing the settings I am using for all three contact curves. As you can see, in the Z direction, they all have the same value as 0. So they are indeed coplanar as they all line on the XY plane. I proceed to define a 2D rigid-to-ridig contact. Attached image, contact.png, shows my settings for one of the contacts I use. I have also made sure to correctly define the contact sides; so there are no problems there either. Finally, attached image, error.png, shows two of the error messages I'm getting. All my error messages are the same so I am only showing those two. It is telling me my curve graphics are not coplanar. However, what it seems is that they actually are indeed coplanar. I would be grateful for any help to fix this problem. Best regards
  4. Hello, I'm modelling a complex structure in Hypermesh with Nastran profile and I need to connect two components. One is a tube meshed with pshell elements while the other is a solid meshed with psolid. The tube is perpendicular to the solid surface but I cannot have the same mesh for various reasons. In Abaqus I would use a tie constraint between the edge of the tube and the surface of the solid but I can't understand how to do so with Nastran and Hypermesh. I tried to use the cards BSURF, BCONNECT AND BCTABLE but I'm not able to figure out how they works. Any suggestions would be highly appreciated. Thank you! Stefano
  5. Hi, I am doing spur gear to spur gear transmission analysis on motionview (gears have module 1 & teeth of the gears are 28 and 82). I used the rigid to rigid type gear contact and used poisson model with parameters as ,penalty = 1000, COR = 1, Normal transition velocity = 1mm/s to define the contact. I gave uniform rotational speed to the gear with 28 teeth and i requested for the output of rotational speed of the gear with 82 teeth. Theoretically i should be getting output plot to be a straight line with slope 0 & 1.024 rad/s (marker velocity) above x axis (time), but i am getting a curve which is not throughout straight line, plot shows a max peak of 7 rad/s velocity as well. What could be the issue for this?
  6. Dear All, I try to do simple heat transfer simulation by following OS-1385. when I run the simulation I got Error 1000 message, I know that the CGAP material does not have material, but in the OS-1385, the CGAP also doesn't have material too. Please your advise. Best regards, Iron_man CASE01.fem
  7. Hello everybody, I'm a Student and have to do a thesis. The thesis is about a FEA about an large bearing. But I'm a beginner in Hypermesh. Does someboby has some tips for modeling of the isssues "initial bolt prestress", "hertzian stress" and general Information which is important to consider?
  8. Hi everyone, I have problem obtaining the TCL command of auto contact pair finding. My model contains 6 components, I use the Abaqus contact manager to automatically find contact pairs for me. Manually, I can successfully find contact pairs. Since I want to run this process automatically by TCL script, I do the process manually and check out the code added in the command.cmf file. Unfortunately, the code are very long, approximately 50000 lines. Also, the code are about nodes' data and surface set, which is not I am looking for. I am looking for the command that represents the buttons "auto", "components: all", "find", "create". I will show these buttons in the figures attached. By the way, the file: raw.hm is my model. Again, my goal is to get the TCL code for finding contact pairs. Please help me, thanks! raw.hm
  9. Hi everybody. I am designing a rapid attach system for the bucket of a skid steer loader (see picture below), taking inspiration from the commercial systems. In the second picture you can see how this system work: there a contact surface between the bucket and the tach. So there is a contact zone and of sure I should do a non-linear quasi static analysis; however since I would not do a non linear analysis I ask you if there is another way to get a solution. I've already done a non linear analysis but I can't validate the results since this kind of analysis should be quite instable. So I'd like to find another way (with linear analysis) just to compare the results. Thanks in advance for your help Best Regards Stefano
  10. Hello, I am doing a study inflating an airbag with a particular shape and there are a lot of contacts between surfaces, that I modeled with interface type 7. I have some troubles because there are some nodes that pass through master surfaces (even if the interface is activated) but then the contact is applied and the nodes can not pass through, creating high contact forces and reducing the time step. I wanted to use the control card DT/INT/DEL to delete the interface in those nodes, I fixed Tscale to 0.9 and Tmin to 1.0 e-4. When I run radioss, time step reduces up to 5e-5, some nodes are deleted but not those that passed through surfaces and have high contact forces. Any idea about how can I deactivate interfaces in nodes where the contact force is higher than a fixed value? Thank you
  11. Dear All, Could you help me to verify, is my simulation valid or not? I do not know because this is first time I use contact in hyperworks my material is steel, with mechanical properties : 1. E = 205000 MPa 2. Poisson Ratio = 0.29 3. Density = 7.85E-6 kg/mm3 4. Yield Strength = 490 MPa 5. UTS = 686 MPa The .hm files is in attachment. Thanks and Best regards, Iron_Man Contact_001.hm
  12. Hello, I have been having issues with a model containing contacts and friction. The model is relatively straight forward, a multiple mast model with wearpads and contacts between pad faces and adjacent mast sections. When the contact is set to property type slide N2S, the analysis demands around 47GB for In-Core Solution. However when the type is set to static friction coeff = 0.15, the in-core demand becomes 80GB. The model on my pc then typically fails because MUMPS demands significantly more RAM. I've tried adjusting the search distance and using a PCONT card to define friction with little impact on MUMPS demand. Any suggestions? I currently have one PARAM card... PARAM,EXPERTNL,CNTSTB
  13. How to define a contact between two surface of shell elements in Nastran profile? Which card image i should use? I created slave and master elements using contact surface collector . Am doing linear static and normal mode analysis.
  14. Hi, Due to contacts in my model I wanna let my optimization run nonlinear. So far the linear analysis and optimization works. To let the analysis and optimization run nonlinear I created a load collector with the card image NLPARM. Additionally I created a non-linear quasi-static loadstep. The nonlinear analysis gives me results where as the optimization does not give any result even though I can let the optimization run without any error. Here I'm uploading a very simplified model that is compatible to the HyperWorks student edition. The contacts are not implemented yet. But there should be contact between the green, the yellow and the blue component. Maybe someone can tell me by which criteria I have to decide if the contact partner is master or slave. I'd be glad to get any advice how I can set up a nonlinear optimization with contacts in Optistruct. My question is: which steps do I have to carry out to turn a linear into a nonlinear optimization. Unfortunately I couldn't find that much information about it. Felix P.S. The model shows a medical implant for connecting bones. Maybe someone is wondering what it is Impl-Mandible-Fib-4S-Uebergang_vernetzt_1_temp13_Federn.zip
  15. I am trying to simulate a quasi-static (NLSTAT) contact problem using Optistruct. I apply a constant displacement on a rigid cylinder which is set apart from a deformable body. The deformable body starts to deform from the beginning of the simulation without contact. As soon as there is contact, the simulation stops without an error message before the prescribed displacement is achieved. What possibly am I doing wrong? Can I use a composite (PCOMPP) as the deformable body in this case? I don`t remember exactly the message but I received an error saying that I could not use it. Also, as i understand from the manual, SLIDE is used for small sliding condition. What should I use if I have finite sliding? Thanks
  16. Please let me know the difference between NF-Resultant Normal Force and Resultant Force. Also what is difference between FX-X Total Force and FNX-Normal Force. I got this values from Radioss Interface output forces. Please let me your comments. Thanks and Regards, Yuvaraj
  17. Hi, I am trying to simulate contact for performing frontal crash analysis of a chassis having a tank. I have a tank which is wrapped by two brackets and supported by rubber. This bracket is welded to a chassis. I need to create contact for the following- 1) Between tank and bracket. 2) Between rubber and bracket. 3) Between rubber and tank. It is attached to chassis as follows- I know that I need to create Interface. Please tell me for each case which Type interface should be used and which should be selected as master and slave? Thank you, Datta
  18. Dear everyone, I have some problems about setting up contacts for two bodies with zero Gap at initial time. Type 7 was used, and two brick solid components were set for slave and master. An error message was received as follows: INTERFACE NUMBER. . . . . . . . . . . . . . 2 INTERFACE TYPE. . . . . . . . . . . . . . . 7 GAP MIN = 0.3000000000000 POSSIBLE IMPACT NUMBER: 77 (<= 1 *NSN) ** INITIAL PENETRATION = 0.3000000E+00 IMPOSSIBLE TO CALCULATE NEW COORDINATES OF SLAVE NODE 380483 ERROR ID : 612 ** ERROR IN INITIAL PENETRATION IN INTERFACE DESCRIPTION : -- INTERFACE ID : 2 -- INTERFACE TITLE : DiPao_WaLengZhi INACTI = 0 SLAVE NODE 380483 IS ON THE MASTER SURFACE ** INITIAL PENETRATION = 0.3000000E+00 IMPOSSIBLE TO CALCULATE NEW COORDINATES OF SLAVE NODE 377618 How to deal with this problem? Could anyone give some advice? Thank you!
  19. Hi all, I would like to model contact between 2 gears (like image in attached file). I took this illustration in a Altair document dealing with contact problems. But, the author do not mention how to implement this kind of contact in optistruct. Does anyone have any idea/advice on how to do this in optistruct? Thanks for your help. GAYE
  20. Hi I'm now working on BirdStrike Analysis using RADIOSS140. Like many paper on birdstrike analysis reports, I've done a reproduction of birdstrike experiment carried out by Wilbeck in 1977 [1]. The resultant pressure PH(*1) and PS(*2) meets with theoretical value very well. Except that,if you look at the pressure curve, there is a "ZERO Pressure" period just after the first contact. Taking closer look into the animation, the SPH bounce back just after the contact. Such blank period doesn't appear in the experiment result,or analysis results of other researchers report. [Question] : Is there a way to correct this ? Model setting is follows. -bird is using SPH. Material law is MLAW6 (Equation of State). -Using contact TYPE7. Istf = 1 StFac = 550 … recommended value by Altair Support Igap = 0 gapmin = h/2 (h = SPH radius) … recommended value by Altair Support I've varied the value of these parameters which didn't make any difference on "ZERO Pressure" period. ******************* *1 … PH: the peek pressure just after the contact(Hugoniot Pressure) *2 … PS: the constant pressure when bird deformation can be seen as constant flow.(Stagnation Point Pressure) [1]:J. Wilbeck,AFML-TR-77-134 1977 161121_Bird Strike experiment reproduction by RADIOSS.pdf
  21. I updated to Hyperworks Desktop 14.0.130 and the Contact Tool is not available in the "Tools" dropdown. It used to be grouped with the Pretension Manager and now it is missing. Where did it go?
  22. Hi all, I'm encountering a problem in a low-velocity impact simulation with a composite plate. As you can see from the image below, at the beginning of the analysis, the impactor literally penetrates the plate but without effective failing of any elements. I experience this problem when I try to simulate the delamination, ply by ply (in my case 16 ply), using very thin shell elements (the thickness of each ply is approximately 0,23 mm). Indeed, after studying the contact problem in LS-DYNA, I figured out that, when very thin shell elements are used, the plate drastically fail when the impactor approaches it. For this reason I had to reduce the SLSFAC from 0.1 to 0.001 in *CONTROL_CONTACT in order to have reasonable results, because the impactor of only 1,5 kg and with an initial velocity of 6,5 m/s destroyed the plate in the very first milliseconds of the simulation without this change. But now, solved one problem (however I'm not really sure about this, maybe someone can explain me better this contact stiffness problem), I have another one I'm using a MAT22 model for the composite and a MAT20 for the impactor (made of steel). To simulate the delamination I chose the *CONTACT_AUTOMATIC_SURFACE_TO_SURFACE_TIEBREAK with 15 delamination model in between, penalty contact SOFT = 0 (justified by the fact each ply is identical) and OPTION = 8 for the failure criteria (I didn't know if PARAM = CCRIT for this option had to be used, so I left it blank). For the contact between impactor and the plate I chose *CONTACT_AUTOMATIC_SURFACE_TO_SURFACE with SOFT = 2 (because of the different materials and meshes), FS=FD=0,5 and with the impactor being the master and all 16 plies being the slaves. Any suggestions to solve this problem? Thanks in advance for any response. impatto.bmp
  23. Hello, I'm trying to run a 3 point bend test. The supports doesn't matter, if possible i would like to make it rigid, but to avoid stress concentration in a point i need to model this contact between the support and the I beam. How can i do this, or find some tutorial more focused ? Thanks !
  24. Hello, 1. I try to simulate a high detailed model of a screw with OptiStruct. Currently the screw will be pretensioned with the pretension function and in the next LoadStep it will be rotated. Now in the following LoadSteps i want to add enforced displacements on the Contact Surface of the screw head. My main problem is the sequence with the enforced displacements. How can every single Loadstep use the results of the previous Loadstep (Stress, Displacement, Contact...)? For the pretension Loadstep i use the function STATSUB(PRETENS), but i dont know if the displacements will be freezed for the next Loadstep and i use CNTNLSUB to consider the contact. 2. The next poblem is, how can i enable/disable contacts between severally LoadSteps without using MODCHG (Older Version of OptiStruct than 14.210)? Thanks!