Prony-based Method for Time-frequency Analysis of Marine Riser VIV Data
نویسندگان
چکیده
Vortex induced vibrations (VIV) of long flexible risers subjected to ocean currents exhibit a strongly nonlinear phenomenon. Although significant efforts have been done for the frequency or time-frequency analysis of this complicated phenomenon, an effective method is still lacking. The objective of this paper is to provide a new method — a Prony-based method — for analyzing the time-varying frequency components of VIV response signals. Physical insight associated with the VIV motion can be further gained through the Prony-based analysis partially because it does not suffer the leakage and frequency resolution problems of the Fourier-based methods.
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