Flow topology of rare back flow events and critical points in turbulent channels and toroidal pipes
C Chin, R Vinuesa, R Orlu, J Cardesa, A Noorani, P Schlatter, MS Chong, J Jimenez (ed.)
THIRD MADRID SUMMER SCHOOL ON TURBULENCE | IOP PUBLISHING LTD | Published : 2018
A study of the back flow events and critical points in the flow through a toroidal pipe at friction Reynolds number Reτ ≈ 650 is performed and compared with the results in a turbulent channel flow at Reτ ≈ 934. The statistics and topological properties of the back flow events are analysed and discussed. Conditionally-averaged flow fields in the vicinity of the back flow event are obtained, and the results for the torus show a similar streamwise wall-shear stress topology which varies considerably for the spanwise wall-shear stress when compared to the channel flow. The comparison between the toroidal pipe and channel flows also shows fewer back flow events and critical points in the torus. T..View full abstract
Awarded by Coturb Grant of the European Research Council
This work was supported with supercomputing resources provided by the Phoenix HPC service at the University of Adelaide. Computer time was provided by the Swedish National Infrastructure for Computing (SNIC). This study was funded in part by the Coturb Grant (grant number ERC-2014. AdG-669505) of the European Research Council. RV, RO and PS acknowledge the funding provided by the Swedish Research Council (VR) and the Knut and Alice Wallenberg Foundation. MSC and CC acknowledge the financial support of the Australian Research Council. We are grateful to A. Ianiro for his thoughtful review of this manuscript.