Hi JTam
its the series on Vibration and Acoustic Fatigue (Vol 1 has the endurance section - variety of curves for aluminium, titanium, carbon and Glare). USAF has data for steel, nickel and glass fibre.
Hi izax1
Blevins' paper is principally for obtaining a fatigue curve under random loading with any peak-to-rms ratio between 2^0.5 and infinity, from sinusoidal S-N data. It can cope with a single term (where the peak to rms ratio is 2^0.5) up to infinity.
I've not used this method, although I...
Hi BenGib
I'm not familiar with the text you quote so I'll not contradict you, but how do you account for the different probability from each environment? The random data has a peak value of 3 time the rms but only 3 times out of every 1000 cycles (you still rack up a lot of "peak" cycles if...
JTam,
the USAF document by Rudder and Plumblee (Rudder, F.F., Plumblee, H.E., (1975), "Sonic Fatigue Design for Military Aircraft," AFFDL-TR-74-112.) gives some rms S-N data and also provides detail on the conversion process. It also gives some useful references. The most relevant being by...
I am familiar with doing transient analysis with NASTRAN where I have been provided with a load/time history. However, I have recently been asked to look at low frequency half sine shock analysis of a structure where the loading has been defined as a table of g levels from 5 Hz to 60 Hz in 5 Hz...
Hi, just some further pointers; the Engineering Sciences Data Unit (ESDU) produces a series of data sheets dealing with Vibration and Acoustic Fatigue - there are data items on the natural frequencies of shell structures. Also Bob Blevins's book "Flow Induced Vibration" has a chapter...
Patrick,
in my (aerospace) work I'm generally supplied 1/3 octave sound pressure levels from the engine manufacturer which suggests broad band random loading. In reality however the noise in the intake of a jet engine is narrow band random and the 1/3 octave levels are actually due to a single...
Hi, I know its been a while since this thread was started but I've only just signed up.
I do a lot of acoustic fatigue work which involves random vibration (evaluation of rms stresses and/or strains). The fatigue data I use is from the Engineering Sciences Data Unit (ESDU) series on Vibration...