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  1. SaeidII

    Sliding Contact for two solids

    Hello, Missil, I am using solid to solid contact. I tried soft method and pinball and the results are similar. Greg, Because the solids are cylinders with different diameters; if they don't slide freely when having radial deformation there will still be forces in the contact plane. I checked the...
  2. SaeidII

    Sliding Contact for two solids

    Hello Sampurna, for Explicit Analysis there must be no difference, since ansys uses ls-dyna code for explicit analysis. Can you please tell more?
  3. SaeidII

    Sliding Contact for two solids

    Hello, I have two solids with different Poisson ratio pushed against each other. Model is analyzed by ls-dyna and I have huge shear stresses on the surfaces of the solids. Contact friction is set to zero; Any idea if this is supposed to be like this? I'd appreciate for your comments.
  4. SaeidII

    Load Curve in LS_dyna

    Hello, I need to implement the strain rate effect on a material model using load curve table. The example for material model 72r3 in ls-dyna manual has used 1/milliseconds for strain rate unit; And now I am confused shall I input strain rate in 1/ms regardless of time unit I am using in the...
  5. SaeidII

    Initial contact between two solids

    Update: adding param,dyconignore*,2 to the bulk file dramatically reduced these stresses; Default value of dyconignore is zero which means initial penetration elimination is enable; But why does it make anything worse?!
  6. SaeidII

    Initial contact between two solids

    Attached image describes the problem better: http://files.engineering.com/getfile.aspx?folder=2ff0636e-363a-42dd-889f-539c9491d009&file=initial_contact.png
  7. SaeidII

    Initial contact between two solids

    Hi, using nastran explicit analysis (sol700) I have noticed if two solids are too close to each other or touching each other; contact stress will be produced on faces of those solids and propagate into model. Since contact thickness offset of solids is zero by default and initial penetration...
  8. SaeidII

    finer Solid Mesh in specific parts of one solid

    Hi, I want fine mesh on the end of a cylindrical rod and coarser mesh on the rest. I could not figure it out how to do that. I tried slicing it using imprint but the created mesh points can't be equivalenced. Any clues? Thank you.
  9. SaeidII

    Make 1D beam work with 3D solid?

    Hi, I have several 1D beams embedded in a solid. I want them to work together e.g. share nodes together. Equivalence option is not giving me the result I want. Do you think there is a way to accomplish this goal? Thank you.
  10. SaeidII

    Unwanted Initial Penetration in touching solids

    I finally figured it out, The touching solids had different mesh types and probably that was the cause of wrong results.
  11. SaeidII

    Unwanted Initial Penetration in touching solids

    Hello, I am having huge unwanted stresses in two solid that are only touching each other. The stresses exist from second time step afterward. With enabling ignore initial penetration(DYCONIGNORE), I was not expecting this behaviour. I have already checked the model and there is no penetration...
  12. SaeidII

    PATH=3 in patran

    Hi, Is it possible to set PATH=3 in Executive Control Section before analyzing the model? I have already tried direct text input in that section but this command should be added after SOL command like: SOL 700 PATH=3 I did not find any build in option to set this either. If you know how to do...
  13. SaeidII

    Element Erosion

    Hello, There is an Erosion material in Patran(materials>create>erosion) in order to implement MATDERO of sol700. MATDERO is not supposed to define a material model but supplements another material model. After defining it I found no option to assign it to another material model I have already...
  14. SaeidII

    Augmentation of Residual Vector

    Hope this will help. There are some information on this in nastran 2001 release guide page 66 and 2004 release guide page 100. good luck.
  15. SaeidII

    How do you define explicit nonlinear materials in patran?

    I could not figure it out how to create materials that are supported by Nastran Explicit NL Analysis in Patran; Documentation says the following materials are not supported in patran: Unsupported Materials in Patran Preference All the material models listed above are supported with the...
  16. SaeidII

    Strange Behaviour: Axisymmetric Model in Patran turns into Shell in Nastran.

    I am modeling a 2D axisymmetric model in Patran using Explicit nonlinear analysis. It's a rod with some forces applied to it's end while the other end is supported. In order to create the 2D model I have used 2D solid property with axisymmetric option. The strange thing is that it seems Nastran...
  17. SaeidII

    Axis of symmetry for Axisymmetric 2D Solid

    Thank you Z.E, very helpful.
  18. SaeidII

    Axis of symmetry for Axisymmetric 2D Solid

    How do you define axis of symmetry for an Axisymmetric 2D solid? It seems there are some rules, but I did not find much information in documentations. Thanks for helping me.

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