Pressure statistics and their scaling in high-Reynolds-number turbulent boundary layers

• Published in: Journal of fluid mechanics Vol. 585; pp. 1 - 40
• Main Authors: TSUJI, Y., FRANSSON, J. H. M., ALFREDSSON, P. H., JOHANSSON, A. V.
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 25.08.2007
• Subjects: Boundary layer; Boundary layer and shear turbulence; channel flow; coherent structures; direct numerical-simulation; Exact sciences and technology; Fluid dynamics; Fluids; Fundamental areas of phenomenology (including applications); High-reynolds-number turbulence; locally isotropic turbulence; Mechanics; overlap region; Physics; pipe-flow; Pressure; Reynolds number; shear-flow; small scales; Statistics; Turbulent flows, convection, and heat transfer; vortical structures; wall-pressure; Large Reynolds number; Pressure fluctuation; Statistical analysis; Turbulent flow; Scaling laws; Experimental study; Boundary layers; Turbulence structure
• ISSN: 0022-1120; 1469-7645; 1469-7645
• DOI: 10.1017/S0022112007006076

Pressure fluctuations are an important ingredient in turbulence, e.g. in the pressure strain terms which redistribute turbulence among the different fluctuating velocity components. The variation of the pressure fluctuations inside a turbulent boundary layer has hitherto been out of reach of experimental determination. The mechanisms of non-local pressure-related coupling between the different regions of the boundary layer have therefore remained poorly understood. One reason for this is the difficulty inherent in measuring the fluctuating pressure. We have developed a new technique to measure pressure fluctuations. In the present study, both mean and fluctuating pressure, wall pressure, and streamwise velocity have been measured simultaneously in turbulent boundary layers up to Reynolds numbers based on the momentum thickness Rθ ≃ 20000. Results on mean and fluctuation distributions, spectra, Reynolds number dependence, and correlation functions are reported. Also, an attempt is made to test, for the first time, the existence of Kolmogorov's -7/3 power-law scaling of the pressure spectrum in the limit of high Reynolds numbers in a turbulent boundary layer.