Acoustic fatigue has been an issue since the introduction of the rocket and jet engines and the response of structures to high intensity acoustic loading. Not only are the levels and subsequent response high, the frequency content means that the number of cycles of stress at particular levels can be produced in a relatively short duration compared to fatigue under other mechanical loading, such as produced by rotating machines.
Aerospace structural fatigue: jet engine nacelles.
This project considered the structural analysis using a dynamic stiffness approach, which is efficient and accurate over a wide range of frequencies and was compared and validated against test in a Progressive Wave Tube (PWT).
Fatigue of structures undergoing a nonlinear response.
The study considered the way that the nonlinear structural response changed the statistics (pdf) of the excitation to produce a response that could be subsequently predicted for fatigue life estimation.
Dynamic response for fatigue test scenarios.
Fatigue testing over a wide range of frequencies, to simulate environments such as random loading from roads on vehicle components or acoustic loads, can be reduced in duration by increasing the loading in various ways. This project has considered the effect of changing the peak distribution (Kurtosis) in the signals in various ways and being able to predict the effect on the fatigue life.
