Assessment of turbulence models for predicting the interaction region in a wall jet by reference to LES solution and budgets

• Published in: Flow, turbulence and combustion turbulence and combustion, 2006-11, Vol.77 (1-4), p.229-255
• Main Authors: DEJOAN, A, WANG, C, LESCHZINER, M. A
• Format: Article
• Language: English
• Subjects: Approximation; Boundary layers; Budgets; Defects; Exact sciences and technology; Flow characteristics; Fluid dynamics; Fundamental areas of phenomenology (including applications); Jets; Physics; Shear layers; Turbulence models; Turbulence simulation and modeling; Turbulent flows, convection, and heat transfer; Wall flow; Wall jets
• ISSN: 1386-6184; 1573-1987
• DOI: 10.1007/s10494-006-9045-3

Highly-resolved LES and experimental data for a plane wall jet are used to study the characteristics of turbulence-closure proposals, mainly within the framework of second-moment-transport modelling. The study is motivated by the observed importance of diffusive Reynolds-stress transport in the interaction region between the outer shear layer and the near-wall layer of the wall jet, which gives the near-wall flow characteristics that are very different from those of a conventional boundary layer. Comparisons are presented for mean-flow quantities, second moments and budgets. Also included are a priori studies of approximations for the pressure-velocity interaction, pressure-fluctuation-driven transport and turbulent transport of the Reynolds stresses by triple correlations, the last observed to contribute significantly to the stress budgets. The study reveals major defects in the closure approximations for the pressure-velocity interaction terms, especially in the near-wall region. These defects result in a poor representation by the particular second-moment closures investigated of even the integral and mean-flow characteristics of the wall jet.