Short-range shock formation and coalescence in numerical simulation of broadband noise propagation

Micah R. Shepherd, Kent L. Gee, Mark S. Wochner

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

The number of jet and rocket noise studies has increased in recent years as researchers have sought to better understand aeroacoustic source and radiation characteristics. Although jet and rocket noise is finite-amplitude in nature, little is known about the existence of shock formation and coalescence close to the source. A numerical experiment is performed to propagate finite-amplitude noise and determine the extent of the nonlinearity over short distances with spherical spreading. The noise is filtered to have a haystack shape in the frequency domain, as is typical of such sources. The effect of the nonlinearity is compared in both the temporal and frequency domains as a function of distance. Additionally, the number of zero-crossings and overall sound pressure level is compared at several distances. The results indicate that the center frequency plays a particularly important role in the amount of coalescence and spectral redistribution that occurs. The general applicability of these results to actual near-field finite-amplitude jet and rocket noise experiments is also presented.

Original languageEnglish (US)
Pages (from-to)2886-2893
Number of pages8
JournalJournal of the Acoustical Society of America
Volume126
Issue number6
DOIs
StatePublished - Dec 29 2009

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noise propagation
coalescing
jet aircraft noise
shock
broadband
rockets
simulation
nonlinearity
aeroacoustics
roots of equations
sound pressure
near fields
Simulation
Jets
radiation
Nonlinearity
Experiment

All Science Journal Classification (ASJC) codes

  • Arts and Humanities (miscellaneous)
  • Acoustics and Ultrasonics

Cite this

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Short-range shock formation and coalescence in numerical simulation of broadband noise propagation. / Shepherd, Micah R.; Gee, Kent L.; Wochner, Mark S.

In: Journal of the Acoustical Society of America, Vol. 126, No. 6, 29.12.2009, p. 2886-2893.

Research output: Contribution to journalArticle

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