'Morning STF,
Thanks for your response and good questions.
I applied a uniform stress across the tapered b-edge of the plate. This tied up with the uniform stress assumption one usually makes with this type of flange. If the stress distribution is non-uniform then the buckling coefficient...
StressMan2506,
You got me going on this one, and I have done some additional work on the subject, which I think you and others here may find interesting and useful. The work, as you will see, has been bench-marked against published papers and my own FEA. The work I have done is contained in the...
StressMan2506,
I have found a reference to tapered flange buckling within a report produced by Y Kim and Teoman Peköz at Cornell University. This work looks pretty well researched and the residing Professor Peköz is well known in the Civil Engineering discipline.
To save you the trouble of...
Hi StressMan2506,
The work is my own, based on some raw results data (the tabulated coefficients) I obtained and calibrated with my own classical and FE analysis. It is important that such FE based data agrees with classical solutions at the points where it can be tested. The transition of the...
Hi Again Stressman2506,
For a typical 2000 series Al alloy, you'll find that the yield stress b/t buckling ratio for a one-edge-free compression panel is close to 10:1. If you apply Needham crippling, this works out at around 8 to 8.5. I.e. it is often used as a guideline for designing...
'Morning StressMan2506,
Find attached a chapter from my personal set of stress notes for a stepped flange of 2 thicknesses across the width of the flange. By carefully estimating the "equivalent" flange to the one you have, using the 2 thickness data, you should get a better estimation of the...
tamz1842,
At present I am separated from my technical database, on an Ipad, so cannot give you a more complete reply. Part V is the correct item I was referring to. There is other Roskam data on the subject which I have which may not be in the public domain. Part V and its semi-empirical inertia...
Hi tamz1842
Obtain a set of Prof Jan Roskam's books on Aircraft Design. He has a whole book/chapter on the subject of typical historical mass/weight data, including inertia data and cross products resulting from asymmetries.
Hope this helps.
Ed
G’Day Eng-Tippers,
A question for detail stress engineers regarding stringer beam-column compression analysis.
It has come to my notice that new forms of skin stringer construction has led to changes in stringer support conditions at the frames or ribs through which they pass. In the past...
G'day Jeff,
This is a bit O/T for this thread, nevertheless I'm sure the authorities won't mind me answering your question.
If you still have an old DOS machine you'd be able to run the s/w. The new pseudo-DOS will not run PAL. As I recall your machine needed to be free of all other s/w in...
Hi Eng-Tippers
I spent the day trawling the Internet and found an item relating to this topic that was published in the Journal of Aerospace Engineering.
The item is titled, “Influence of Head Geometry on Bolted Joint Behavior”. It appeared in Vol. 15, Issue 4 (October, 2002) of the Journal...
Sparweb,
Thank you for your words of wisdom regarding this problem. You are quite right regarding my needing some test data for a 130 deg flush head fastener. In the past, I have used known techniques for reverse engineering fastener data to obtain what I need for an application that was not...
Wil..
Thanks for responding.
The fasteners I have encountered, "Hi-lok" types, blinds and secondary structure bolts, have had large airframer fastener codes allocated to them, so I don't know where they originate from. Most are Ti alloy and in the 3/16 to 1/4" dia. range. Where I work, we...
G’day Eng-Tippers,
I have a question that a colleague and I are puzzling over.
Does anyone here have a method for correcting 100 degree flush head fastener data in aluminium sheet for other higher angle flush head fasteners? My reverse engineering of the sparse 120 degree data in the MMPDS...
