Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

Register Log in
  • Congratulations TugboatEng on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Recent content by MarkCopland

  1. MarkCopland

    How to constrain a closed ring beam element for 90, 180 degree symmetr

    I don't get these buckling load ( 209 !!!!). and I habe been playing with all BC possible. and including 3D solid model. I tried to do it and I don't get the same, could you let me know what are the frequency of your model ( just for me to verify) and what is the stress for your static...
  2. MarkCopland

    buckling shape of a solid ring

    please I will aprecite it
  3. MarkCopland

    How to constrain a closed ring beam element for 90, 180 degree symmetr

    Thanks rb1957 To be more clear: 1) Load is: newtons per unit length ( N/mm)..not pressure (let try not confuse with my original case post..let run the simple case as described before). 2) Before to run a skin model for load distribution, let set the model for as simple ring as described before...
  4. MarkCopland

    How to constrain a closed ring beam element for 90, 180 degree symmetr

    crisb, Could you let me know what are your constrains for your model. did you modeled as a full 360 Degree model?. Which one is your software?.
  5. MarkCopland

    How to constrain a closed ring beam element for 90, 180 degree symmetr

    software is mechanica from proe WF4. element a beam element with 25x25 section.
  6. MarkCopland

    buckling shape of a solid ring

    How to calcuale the in-plane and out-plane buckling factor for s simple solid ring under external pressure?.
  7. MarkCopland

    How to constrain a closed ring beam element for 90, 180 degree symmetr

    Thanks all. Sorry if I mix up some numbers. Let fix the case for future reference to R= 1000 mm . Square section: 25x25 mm I: 32552 mm4 Yes, material is steel E=193053 N/mm Load case: unitary external force 1 N/mm (since my benchmark model is beam element) Timoshenko buckling pressure: 18.85...
  8. MarkCopland

    buckling shape of a solid ring

    Does any body know the equation for the buckling modes for a solid ring under external pressure. inplane and outplane modes? related forum: http://www.eng-tips.com/viewthread.cfm?qid=287836&page=1
  9. MarkCopland

    How to constrain a closed ring beam element for 90, 180 degree symmetr

    Hello John I am trying to model a fuselage section, basically simple assumed as a one support ring and a cylindrical shell skin under external pressure. (like a submarine)…. I want to see the stress in the ring, as you could image, the ring is free in the space but supported by the shell skin...
  10. MarkCopland

    How to constrain a closed ring beam element for 90, 180 degree symmetr

    CORUS: Well, the only way for a model to run without constrains is for modal analysis only, so I will agreed that the first 6 modes will give you the 6 rigid movements, but for a Buckling analysis with not constrains I don’t see how to do it (and I will guest is not possible). I am looking to...
  11. MarkCopland

    How to constrain a closed ring beam element for 90, 180 degree symmetr

    I get solution with case A and Case B, but the 360 degree case, How do I do?.. I am fixing translation and rotation for X, Y, Z in just one point, I get the same stress in all 3 cases, but only deflexion in case A and B are the same, for case C not,,, so when I do a buckling analysis I get...
  12. MarkCopland

    How to constrain a closed ring beam element for 90, 180 degree symmetr

    How to constrain a closed ring beam element for 90, 180 degree symmetry cases under external pressure. I need help to define the following simple constrain beam case I got a “circular closed ring” with a square profile 25x25 mm and an mean radius of 518 mm, material steel, the ring is has a...
  13. MarkCopland

    How to determine if vortex shedding will occur?.

    How to determine if vortex shedding will occur?. This question is more from the theory point of view rather form a CFD simulation point of view. With given object dimensions and speed moving inside a fluid. How do I decide if vortex shedding will occur knowing a strouhal number?. Does it mean...
  14. MarkCopland

    "Infinity friction" in contacts - When use it?

    Hello, Pio3 and Petiesmo. I got two different points regarding with the FEA analysis that Pio3 is doing. Regarding with the fea analysis in plastic like material, please have a look at the thread “ Pro/mechanica and plastic like materials”, so we don’t mix opinion in this thread. Now...
  15. MarkCopland

    Pro/mechanica and plastic like materials

    Pro/mechanica and plastic like materials. I have done some FEA analysis in metal parts using promechanica lineal analysis with WF3, with WF4 the hyperplasic model were introduced (so elastomers material like rubber) can be analysed, and now in WF5 elastoplastc material were introduced, both...
See more

Part and Inventory Search

Back
Top