Analysis of large vortical structures in shear layers

McInville, R. M.; Hassan, H. A.; Gatski, Thomas B.

doi:10.2514/3.9059

Cited by 16 publications

(2 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…But this cause the mixing layer to be destabilized and the vorticity thickness grows again due to the increased amplification rates at further downstream locations. Similar observations were reported by McInville et al 54 and Stanley and Sarkar 41 ; (4) for the same reason, the contraction or expansion of the mean flow will make the fluctuating part to gain energy from or loose energy to the mean sheared flow. This will exhibit as alternating positive and negative Reynolds stress reported by Stanley and Sarkar, 41 but they are not shown here for brevity.…”

Section: Hydrodynamic Fluctuationssupporting

confidence: 83%

Hydrodynamic sources of the vortex sound in a two-dimensional shear layer

Liu

et al. 2023

International Journal of Aeroacoustics

View full text Add to dashboard Cite

Development of advanced noise reduction devices requires an in-depth understanding of two fundamental questions: what are the true noise sources and how are the acoustic radiations generated. An accurate separation of the hydrodynamic and acoustic fluctuations helps to reveal the answers, but no consensus exists on its feasibility in the near-field source region of compressible flows. This study proposes a methodology to examine the dynamics of vortex sound generation in a two-dimensional artificially excited subsonic mixing layer. The parabolized stability equation (PSE) is applied to resolve the hydrodynamic fluctuations and the vortex sound theory is used to predict the acoustic pressures. Numerical simulations show that the PSE solutions capture the vortex pairing reasonably accurately and damp the acoustic modes to a negligible level, and that the vortex sound theory recovers the acoustic pressures. Good agreement of both solutions with the direct simulations indicates that a physically reasonable separation of hydrodynamic sources is achieved and can be used to further examine the vortex dynamics and noise source mechanisms.

show abstract

Section: Hydrodynamic Fluctuationssupporting

confidence: 83%

Hydrodynamic sources of the vortex sound in a two-dimensional shear layer

Liu

et al. 2023

International Journal of Aeroacoustics

View full text Add to dashboard Cite

show abstract

“…The reverse transfer in momentum maybe due to presence of pressure gradient as explained above or maybe due to the nature of initial disturbances. If disturbances are present, it has been found (McInville et al, 1985) that the phase angle between the forcing wave and the initial response wave greatly affects the shear layer structure. Depending on this angle, merging of vortex structures to form larger vortices can be inhibited and even totally eliminated resulting in the collapse of the shear layer growth.…”

Section: Shear Laver Thicknessmentioning

confidence: 99%