A second-order consistent time-resolved database of turbulent channel flow up to $Re_\tau \approx 5000$

Wall-bounded flows play an important role in numerous common applications, and have been intensively studied for over a century. Understanding the fundamental mechanisms of the logarithmic and outer regions is essential for the development of effective control strategies and for the construction of a complete theory of wall-bounded flows. A proper analysis of the logarithmic and the outer layers requires time-resolved simulations at high Reynolds numbers in large domains, which makes the storage of the time series impractical. We present a novel low-storage method for time-resolved simulations. By retaining only the large and intermediate scales, while taking care to keep all the variables needed to fully reconstruct the flow at the level of second-order statistics, we reduce the storage requirements by a factor of $10^3$. This new methodology is efficiently implemented by using a new high-resolution hybrid CUDA-MPI code, which exploits the advantages of GPU co-processors on distributed memory systems, and allows to run for physically meaningful times. Databases for channel flows at up to $Re_\tau=5300$ in large boxes $(8\pi h\times 3\pi h)$ for over 30 turnover times, are presented.