News: Need training? HyperSizer Training Videos are available now! Learn more here: https://hypersizer.com/trainingevents/e-learning/

Author Topic: Modifying stiffnesses in HyperFEA  (Read 12263 times)

Phil

  • Administrator
  • *****
  • Posts: 218
    • HyperSizer Structural Sizing Software
    •  
Modifying stiffnesses in HyperFEA
« on: May 28, 2010, 10:45:02 AM »
In the HyperFEA process, it is possible to tell HyperSizer to modify the stiffnesses to limit deflections and/or eigenvalues.   The components that are to be modified and the degrees of freedom that are modified are specified in the *.UIN file (which can be created using the "Displacement and Eigenvalue Limit" button on the Options form in HyperFEA).  Two questions have recently been asked in emails:

1) are the assembly names supposed to begin with the word "ASSEMBLY: " as shown in the user manual?

No, the assembly names shown in the user manual are just examples.  The names specified in quotes in the UIN file must match the Assembly names in HyperSizer exactly in order to be affected.

2) There was a question about what stiffnesses get modified with the various DOF flags in the UIN file...  Here is the map:

DOF     Panel Stiffness       Beam Stiffness
---       ---------------     ------------------
1           A11                    EA
2           A22                    EA
3           A33                    EA
4           D11                    EI1
5           D22                    EI2
6           D33                    GJ

It might look funny that EA is associated with 1, 2 and 3, but they are grouped by function... A11, A22, and A33 are "in-plane" stiffness terms for a panel... the only stiffness of a beam that would correspond to this function is the axial stiffness EA.

D11 and D22 are bending stiffnesses of a panel and EI1 and EI2 are bending stiffnesses of a beam.  D33 is twisting stiffness of a panel, GJ is twisting stiffness of a beam.
« Last Edit: May 28, 2010, 10:46:53 AM by Phil »