A structure-based model for turbulent-boundary-layer wall pressures

• Published in: Journal of fluid mechanics Vol. 650; pp. 443 - 478
• Main Authors: AHN, B.-K., GRAHAM, W. R., RIZZI, S. A.
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 10.05.2010
• Subjects: Boundary layer; Boundary layer and shear turbulence; Boundary layers; Eddies; Exact sciences and technology; Experimental data; Flow velocity; Fluid dynamics; Fluid mechanics; Fundamental areas of phenomenology (including applications); Physics; Reynolds number; Turbulence simulation and modeling; Turbulent flow; Turbulent flows, convection, and heat transfer; Pressure fluctuation; Wall turbulence; Turbulent flow; Digital simulation; Modelling; Boundary layers; Turbulence structure
• ISSN: 0022-1120; 1469-7645
• DOI: 10.1017/S0022112009993727

Practical prediction of structural vibrations due to a turbulent boundary layer currently depends on empirical representations of the unsteady wall pressures. Improvements in these representations would be greatly facilitated if a simple, physically based model were available to test ad hoc assumptions and provide rigorous interpolation of experimental data. A possible candidate is the attached-eddy model, developed from Townsend's initial ideas by Perry and co-workers in the context of turbulence velocity spectra. This approach employs the superposition of contributions from individual ‘eddies’, of varying size, to yield its predictions. It is shown here that the same methodology can be applied for wall pressures, once the field due to an eddy has been obtained via solution of the governing Poisson equation. Comparisons with large-eddy simulation and experimental data, spanning a two-decade Reynolds number range, show remarkably good agreement, given the simplicity of the model. It is concluded that this approach has the potential to provide useful physical insight and, subject to its extension to a time-resolved form, improvements to existing empirical formulations.