Direct numerical simulation of turbulent pipe at high Reynolds numbers, velocity statistics and large scale motions

In recent years there has been a considerable research effort dedicated to turbulent pipe flow. Topics of interest are, amongst others, the scaling of near wall turbulent statistics and the existence of very large scale turbulent structures at higher Reynolds numbers. These structures have been observed experimentally in boundary layers, Hutchins & Marusic (2007) and pipes, Monty et al. (2007). Recently these structures have also been observed in moderate Reynolds number direct numerical simulations of channel and boundary layer flows. In this paper we will report on the simulation of turbulent pipe flow at bulk Reynolds numbers of 24600, 37500, and 75,000. The numerical grid (up to 7.6e9 grid nodes) is comparable to the grid used by Jimenez & Hoyas (2008) and should be sufficiently fine to resolve all scales. At high Reynolds numbers we observe some evidence of the aforementioned long scale structures.