Hello all,
I've been trying to perform an FEA simulation of a membrane wrinkling in tension in ABAQUS 6.7. It's a 100 mm x 100 mm square Kapton (.013 mm thick, 2600 MPa secant modulus, v = .34) membrane meshed with S4R5 elements with an element size of about 1.33 mm. It's in the xy-plane, and...
Alright, well, I got it to work in NASTRAN. I was wondering, though, what do these parameters correspond to in I-DEAS 12? I checked the help library, as well as the Physical Properties icon under Meshing. I don't know where else it could be, though I know I've seen it somewhere.
I went over my model set thoroughly with my manager, and after talking to him about some of the suggestions made by you guys, he deduced that the varying errors in deflection/stress are in fact a by-product of the inaccuracy of beam theory, and not any eccentricities or mistakes in the model...
Yeah, checked those. While there are out-of-plane deflections, they are a couple orders of magnitude smaller than the bending deflections, as predicted by btrueblood's data. There is in fact a large jump in the % error for the stress data around the loads. I guess what I was asking was why the...
fetraining:
I got I-DEAS to export the model file as a .dat file to use with MSC/Nastran. I will fiddle around with that later today and see what I get.
rb1957:
What I did was use a constraint element to tie the node at the end face's midpoint to all the other nodes on the face. Then, I...
Thanks for the reply. This is where things get strange. With respect to stiffness, the max stress and max deflection values are all greater in magnitude than what is given by theory. During mesh convergence, I saw that though the models were converging, rather than diverging such that max...
rb1957,
For the beam element model of the I-beam, I am using the beam section property tool in I-DEAS to create an I cross-section with the proper dimensions. The beam elements are oriented along the length of the beam. Also, what do you mean by 'mixing' singularities? Thanks for the help.
Thanks for replying. I looked at the .dat file of the model from NASTRAN, and everything checks out...geometry, forces, DOF, moments of inertia, etc. I don't think that's it.
I am having some trouble getting accurate values for max. stress and max. deflection for an FEM model of a simply supported I-beam in bending. I am using I-DEAS 12 NX to solve the model. I'm pretty new to finite element analysis as a whole, but I know that getting any more than 10% error...
