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Despite the high relevance of wall-bounded turbulence for engineering andnatural science applications, many aspects of the underlying physics are stillunclear. In particular, at high Re close to many real-life scenarios, the truenature of the flow is partially masked by the inability of numericalsimulations to resolve all turbulent scales adequately. To overcome this issue,we aim to numerically investigate fully-developed turbulent pipe flows atmoderate-to-high Re ($361 \leq Re_\tau \leq 6,000$), employing LES. A gridconvergence study, using the WALE subgrid stress model, is presented for$Re_\tau=361$. Additionally, the prediction accuracy of distinct subgrid-scalestress models, such as WALE, SMG, OEEVM, LDKM, and DSEM, is examined using arange of statistical measures. The results infer, as expected, that SMG andOEEVM are too dissipative, whereas WALE, LDKM, and, more surprisingly, DSEMperform rather well compared to experiments and results from DNS. Moreover, LESutilizing WALE are performed and investigated in detail for six differentReynolds numbers in the interval from $Re_\tau = 361$ to $6,000$ with graduallyrefined grids. These computations allow an insight into what turbulenceinformation is retained when LES with a wall model is applied to such highReynolds numbers in the limit of a relatively coarse grid. Second-orderstatistics for all values of $Re_\tau$ exhibited excellent agreement with theDNS data in the outer region. Surprisingly, results also revealed a dramaticdeviation from the DNS data in the sub-viscous layer region irrespective of the$Re_\tau$, attributed to the considered scaling for mesh refinement. Overall,the WALE model enabled accurate numerical simulations of high-Reynolds-numberwall-bounded flows at a fraction of the cost incurred if the inner layer wastemporally and spatially resolved.

Large Eddy Simulations of Fully-Developed Turbulent Pipe Flows At Moderate-To-High Reynolds Numbers