Precursors to self-sustained oscillations in aeroacoustic systems. Issue 3 (April 2016)

• Record Type: Journal Article
• Authors: Nair, Vineeth; Sujith, RI
• Is Part Of: International journal of aeroacoustics. Volume 15:Issue 3(2016)
• Page Start: 312
• Page End: 323
• Publication Date: 2016-04
• Subjects: aeroacoutics -- Nonlinear dynamics -- Precursors; Aerodynamic noise -- Periodicals; Acoustical engineering -- Periodicals; Sound -- Periodicals; 629.1323
• DOI: 10.1177/1475472X16630877
• Languages: English
• ISSNs: 2048-4003

Abstract

In this study, we attempt to provide a repertoire of measures to forewarn the onset of impending flow-induced mechanical oscillations via online health monitoring. To illustrate the principles, the flow of air through a pipe terminated by a circular orifice plate is investigated at various flow velocities using a suitably placed pressure transducer. It is observed that the regimes corresponding to the production of a tone is presaged by operating conditions that display temporarily intermittent bursts of periodic pressure oscillations that emerge from a background of lower-amplitude aperiodic fluctuations. The various model-free measures prescribed in this paper serve as efficient precursors by characterizing these intermittent states, which can potentially arise in aeroacoustic systems when the flow is highly unsteady or turbulent.