Academic Journal

An experimental study of the wall-pressure fluctuations beneath low Reynolds number turbulent boundary layers

التفاصيل البيبلوغرافية
العنوان: An experimental study of the wall-pressure fluctuations beneath low Reynolds number turbulent boundary layers
المؤلفون: Van Blitterswyk, J. (Jared), Rocha, J. (Joana)
المصدر: Journal of the Acoustical Society of America vol. 141 no. 2, pp. 1257-1268
سنة النشر: 2017
المجموعة: Carleton University's Institutional Repository
الوصف: A more complete understanding of the physical relationships, between wall-pressure and turbulence, is required for modeling flow-induced noise and developing noise reduction strategies. In this study, the wall-pressure fluctuations, induced by low Reynolds number turbulent boundary layers, are experimentally studied using a high-resolution microphone array. Statistical characteristics obtained using traditional cross-correlation and cross-spectra analyses are complimented with wall-pressure-velocity cross-spectra and wavelet cross-correlations. Wall-pressure-velocity correlations revealed that turbulent activity in the buffer layer contributes at least 40% of the energy to the wall-pressure spectrum at all measured frequencies. As Reynolds number increases, the low-frequency energy shifts from the buffer layer to the logarithmic layer, as expected for regions of uniform streamwise momentum formed by hairpin packets. Conditional cross-spectra suggests that the majority of broadband wall-pressure energy is concentrated within the packets, with the pressure signatures of individual hairpin vortices estimated to decay on average within traveling ten displacement thicknesses, and the packet signature is retained for up to seven boundary layer thicknesses on average.
نوع الوثيقة: article in journal/newspaper
اللغة: English
Relation: https://ir.library.carleton.ca/pub/12270
DOI: 10.1121/1.4976341
الاتاحة: https://ir.library.carleton.ca/pub/12270
https://doi.org/10.1121/1.4976341
رقم الانضمام: edsbas.E24E485C
قاعدة البيانات: BASE