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!

Search results for query: *

  1. BennyS

    MSC Nastran Edge-To-Surface Glue

    Hello community, due to various circumstances I have to switch from Siemens NX Nastran to MSC Nastran. I used glueing operations for different purposes like edge-to-surface and surface-to-surface. Now, as I have to switch to MSC, I want to transfer these connections. I read a bit about the MSC...
  2. BennyS

    Find coincident faces (touching faces) between two (or multiple) bodies

    Hi all! Currently, I want to identify the face pairs which depict interfaces between 2 or more components in NX using NX Open. These faces are faces which are coincident/touching with a face of the other body. For this, I already did some research concerning existing methods, as there are for...
  3. BennyS

    Stiffness matrix of simple shell element (Simple reasoning?)

    So, to sum up my latest information. I analysed a simple CQUAD4 and I realized that varying Young's Modulus or Plate thickness IS influencing also the in-plane rotational DOF. So my previous statement that changing the young's modulus is not influencing these stiffness matrix entries but the...
  4. BennyS

    Stiffness matrix of simple shell element (Simple reasoning?)

    Thank you all so far for your responses. @gravityandinertia : Okay I think i used "analytical" in a wrong way. To summarize it: I have a structure (does not matter how it exactly looks). I want to stiffen it by factorising the e-modul by 10%. The other approach I want to compare to, is that...
  5. BennyS

    Stiffness matrix of simple shell element (Simple reasoning?)

    Thank you gravityandinertia. I already know something about equations of motions, and I was aware about the relation between stiffness matrix and DOF vector. My problem was that I had in mind, that the kind of element AND the kind of DOF(translational or rotational) play a role for the value of...
  6. BennyS

    Stiffness matrix of simple shell element (Simple reasoning?)

    But the DOF of a Grid Point do have an entry in the stiffness matrix, right? So, rotational DOF1 of grid point 1 is connected to rotational DOF1 of grid point 2 (beam example).So according to my understanding, it is possible that the factors of translational stiffness and rotational stiffness...
  7. BennyS

    Stiffness matrix of simple shell element (Simple reasoning?)

    Hi IDS, thanks for your response. for ANY type of element? I found some literature which says that the material properties are included as a "Material property Matrix". (e.g. shell elements) Where also the Poisson's ratio etc are included. For this reason I was not competely sure, if the...
  8. BennyS

    Stiffness matrix of simple shell element (Simple reasoning?)

    Thanks for your responses. I try to set-up the matrices to check a problem using a rather "analytical" or scientific approach. I would require something that connects the young's modulus to the stiffness terms in the matrix. I want to show that varying the young's modulus by 1% is influencing...
  9. BennyS

    Stiffness matrix of simple shell element (Simple reasoning?)

    Thank you for your response :) I guessed that, but is it really so hard to set-up the stiffness matrix of a simple 5mm*5mm*1mm shell?
  10. BennyS

    Stiffness matrix of simple shell element (Simple reasoning?)

    Hi together, I struggle a lot with the task to set-up a stiffness matrix for a simple shell element. In Nastran, I have a 5x5mm flat shell with 1mm thickness (isotropic), represented by a CQUAD4 element. Can somebody explain an easy way to setup the corresponding stiffness matrix? I already...
  11. BennyS

    Stiffness variation approaches in Nastran

    Hi all! I have an issue and I don't know any reason for the problem :( I have a structure consisting of two structures connected on one edge. In the basis model which is a beam, it all seems to be OK. But now I want to go into more detail. My target body is an axisymmetric structure consisting...
  12. BennyS

    Shell vs Solid element

    Hi together!:) I have got a really fundamental problem and I would be very very grateful if someone could help me here :) I am trying to explain the reasons for the deviations of my simplified model. It's a simple rectuangular body similar to a beam with fixed constraints on one end and a load...

Part and Inventory Search

Back
Top