XXII ICTAM, 25–29 August 2008, Adelaide, Australia ON THE RELATIONSHIP BETWEEN LARGE- AND SMALL-SCALE MOTIONS IN TURBULENT BOUNDARY LAYERS
نویسندگان
چکیده
The relationship between largeand small-scale motions remains a poorly understood process in wall-bounded turbulence. Investigation performed by Hutchins and Marusic [3] in a high Reynolds number turbulent boundary layer has recently revealed a possible influence of large-scale log region motions on the small-scale near-wall cycle, akin to a pure amplitude modulation. For this study we build upon these observations, using the Hilbert transformation applied to the spectrally filtered small-scale component of fluctuating velocity signals, in order to determine the degree of amplitude modulation effect imparted by the large-scale structures onto the near-wall cycle.
منابع مشابه
Large-scale amplitude modulation of the small-scale structures in turbulent boundary layers
In this paper we investigate the relationship between the largeand small-scale energy-containing motions in wall turbulence. Recent studies in a high-Reynoldsnumber turbulent boundary layer (Hutchins & Marusic, Phil. Trans. R. Soc. Lond. A, vol. 365, 2007a, pp. 647–664) have revealed a possible influence of the largescale boundary-layer motions on the small-scale near-wall cycle, akin to a pure...
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