btrueblood: I'm looking at Alibre. Have you done anything with it yet?
All the rest: Thanks for the input. Interesting to see the range of programs used, didn't seem to be a clear consensus, same as the other threads I read.
Merry Christmas!
Rick Fischer
Retired Principal Engineer...
I searched free CAD here and saw several mentions for FreeCAD. Lots of how-to stuff on U2B.
Rick Fischer
Retired Principal Engineer
Argonne National Laboratory
Im a recently retired engineer with an occasional need to draw stuff. Im on a fixed income (actually not fixed, it's broken, as in no income, just out go) so I need to control my costs. Im looking for a free cad package. Any recommendations?
Rick Fischer
Retired Principal Engineer
Argonne...
The use of principle stresses allows you to differentiate between tensile and compressive stress fields, while von Mises stress does not. Note that the modified Goodman diagram includes behavior for σm<0. This would suggest that the principal stress is a better choice. However fatigue damage...
I'm not all that familiar with epoxy. However:
1. Creep is not basically a reduction in elastic modulus. That is a crude idealization so that creep effects can be included in simple hand calculation. Creep is time dependent plastic flow.
2. Epoxy is crosslinked, so its thermoplastic. Creep...
See if you can find "Determination of Weld Loads and Throat Requirements Using Finite Element Analysis with Shell Element Models - A Comparison with Classical Analysis" by M. A. Weaver.
Rick Fischer
Principal Engineer
Argonne National Laboratory
I assume you are talking about a test on a finished part with typical service loads. The rate of thermally activated processes in polymers (and a lot of other stuff) typically follows an Arrhenius distribution for temperatures below the glass transition temperature, so in theory this could be...
First, don't even try to understand polymers by comparing them to metals. These are two entirely different material families with entirely different atomic structure, different bonding, different everything. You will only confuse yourself and suffer irreparable brain damage. Second, a tensile...
"The washer is bonded to the plate with compatible meshes." Actually, it is no longer a washer on a plate, its functionally a plate with a boss. But analytically its two pieces stuck together with an idealization, and you are looking at stress at the idealization and trying to hand wave goofy...
You can have shared topology, but you have to select the elements on the edge of one of the parts to be joined by the weld, and then select the nodes on that edge. Put a local CSYS at the origin of the weld group, and set the SPOINT as the global coordinates of the local CSYS. Set the RSYS to...
Try selecting only the elements on the part with the hole with the forces. If all the elements are selected, the reactions sum to zero, as your plot shows. Thats why it works for bonded contact and not shared topography. And dont forget SPOINT at the centroid of the weld group so your moments...
Workbench does not include any geometry (keypoints, lines, areas, etc) in the .db file, so APDL will have nothing to find. The best you can do is get the node at the kp locations. See the attached
Rick Fischer
Principal Engineer
Argonne National...
Your script does not display for me.
Is this a static analysis? What are your material models? Anything that is time or rate dependent? Creep, visco, etc?
/prep7
block,0,12,0,1,0,.25
et,1,186
esize,.125
vmesh,all
ex,1,29e6
nuxy,1,.3
nsel,s,loc,x,0
d,all,all,0
nsel,s,loc,x,12
f,all,fy,-5...
First, if this is a simple static analysis without time dependent material properties (creep, for instance), TIME,150 means nothing. For a static analysis TIME is just an integer identifying a load step. Second, if you issue a AUTOTS,OFF command after NSUBST,50,1000,10, you will get 50 evenly...
If you are so convinced that it CANNOT be learned on your own, why are you bothering us? Yes, you can learn it yourself, if you really want to. I just taught myself how to analyze an electromagnet to determine flux density and Maxwell forces with the old unmaintained and unsupported low...
See attached. Just click on the box to the right of the * and type a temperature. That creates the next line to fill in yield and tangent modulus.
Rick Fischer
Principal Engineer
Argonne National...
I heard someplace that the only issue with burning bags is the ink used to print store names an logos on the bags. I think it contained stuff like lead and arsenic. If true, stop printing on the bags and its pretty safe to burn, right?
Rick Fischer
Principal Engineer
Argonne National Laboratory
I don't get it. Get in help and search on HSFLD242 and the inflating and rolling tire problem is right there. Google HSFLD242 and the PADT hit is like #5, after a good one from Simutech. This is easy. Why cant Iakasa do it for himself? He won last long in the profession if he pulls this on...
