要約

Well-resolved large-eddy simulations (LES) of a spatially developing turbulent boundary layer under zero pressure gradient up to comparably high Reynolds numbers (Re_θ = 4300) are performed. The inflow is located at Re_δ* = 450 (Re_θ ~ 300), a position where natural transition to turbulence can be expected. Results are validated and compared extensively to both numerical data sets (e.g. an on-going fully-resolved spatial direct numerical simulation (DNS) up to Re_θ = 2500) and available experimental measurements, e.g. the ones obtained by Osterlund et al. (1999). The goal is to provide the research community with reliable numerical data for high Reynolds-number wall-bounded turbulence, which can in turn be employed for further model development and validation, but also to contribute to the characterisation and understanding of wall turbulence.
The results obtained via LES show that good agreement with existing data, both numerically at lower Reynolds numbers and experimentally, can be obtained for both mean and fluctuating quantities. In addition, turbulence spectra characterising large-scale organisation in the flow have been obtained and compared to literature results with good agreement. In particular, the near-wall streaks scaling in inner units and the outer layer, large-scale structures can clearly be identified in both spanwise and temporal spectra. The present contribution focuses on presenting selected results, in an effort to validate the chosen simulation approach and to initiate further studies analysing the simulation data.