I don't know if this is of interest to anybody here--there was a "Climate Change Statement Review" published online, written by the Climate Change Statement Review Subcommittee of the American Physical Society (APS), dated Dec. 20, 2013 which outlines a number of questions that the committee...
wktaylor: I am not the source of the documents, I am merely the messenger--I have no idea where the documents originated, so have no way of verifying what you say is right or wrong.
I posted those two documents merely for the eng-tips.com forum readers' convenience. The location I previously...
Anybody out there use WARP3D before? I'd be interested in what you think of it--how much effort to get up and running? If you have experience with other FE software that has nonlinear fracture mechanics capabilities, how does it compare to those other software?
What 'stress distribution' is assumed in the elements a priori? The only "distribution" that is assumed is the form of the displacement field. You start with pointwise equilibrium of the spatial derivatives of the stresses, which is not the same as assuming the stress distribution itself.
If I am indeed calculating strains/stresses when I solve the FE equations, then shouldn't I be able to directly extract stress as say Node 1 (or some other points) without any more work? I can do this with the displacements--the "u" in Ku=f is my solution; therefore (if I used isoparametric...
I still don't think you need to know anything about the stresses to compute the displacements. You are enforcing equilibrium of stresses, but only in a global sense through the integrals of the principle of virtual work, which is one reason why they call the principal of virtual work "the weak...
Thanks feajob. This reference I missed. Was this the source of the "superconvergent patch recovery" technique I've heard about? I've seen a few papers recently that discussed proofs for particular cases.
Even if the water is shallow, you can have trouble finding it--a heli went into Lake of the Ozarks, in Missouri in 2008 (a man made lake whose waters are 'murky'); they knew exactly where it went in, because there were witnesses nearby. Took authorities 2 days to find it. I didn't hear...
Try again. Sorry, I mistakenly deleted it.
www.apesolutions.com/spd/public
Let me know in this forum if you have a problem with
any of the files (perhaps there was a problem transferring files from my computer to the download site; if so, I can try to recopy the file(s) and see if that...
Incidentally, I doubt very much my use of 1D elements to illustrate that the stresses aren't actually computed directly until after the solution (the displacements) are found was 'specious'--the derivation of 1D, 2D and 3D finite element matrices have many many similarities that illustrate the...
My question had nothing whatsoever to do with the difference between measured and calculated stresses. My question had to do with the general principle of assuming calculated stresses are more accurate at the integration points than they are at the nodal points. My assumption was that was a...
The location of the two documents--the original training course and the answer key, has apparently moved. You can get the following two documents:
Stress_Course_for_Liasion_Engineers.pdf
Aircraft_Structures_for_Engineers___Solutions.pdf
now at following website...
Apparently, we are all reading different finite element textbooks, each with its own set of messages that the authors mean to convey. Therefore, we each have a different knowledge basis for comparing what we think we know about things like FE and what others seem to know. For instance, I learned...
After more research, I am still stumped. Though I do have a few papers whose authors make the same claim about 'stresses at the integration points being more accurate than at the edges' matter of factly. So I have some more digging to do to figure out why. One person I know uses ANSYS I think...
Apparently others here think that there are other ways to compute stresses than the obvious one (using spatial derivatives of the solution vector), so I'll do some more research to see what others are doing. I can't imagine how you can use the stiffness matrix and the solution vector to compute...
pja-thanks for the reference. I have only 3rd edition of Cook, Concepts and Applications of Finite Element Analysis, available. Could you possibly supply the Chapter and section number (and/or title) to help me zero in on the correct section, since almost undoubtedly the pages are different from...
Not to sound overly critical, but have you ever constructed by hand a 'finite element'? It appears not, since you have stated that stresses and strains are needed.
To illustrate, I think I don't lose any generality by describing how the finite element matrix is constructed in 1D, for rods. We...
rb1957
Are you referring to NACA TN 2073? Stress and Strain Concentration at a Circular Hole in an Infinite Plate, by Elbridge Stowell? Published in 1950.
What is the basis for the statement "stresses are implicitly calculated from the solution to Ku=f"? In a linear solutions, where are stresses (or strains for that matter) in "K," "u" or "f"? No, stresses are calculated AFTER you compute the displacement vector "u", by computing, as you know, the...
