Transient dynamics of accelerating turbulent pipe flow
Byron Guerrero, Martin F Lambert, Rey C Chin
Journal of Fluid Mechanics | CAMBRIDGE UNIV PRESS | Published : 2021
The transient dynamics of accelerating turbulent pipe flow has been examined using direct numerical simulation (DNS) data sets with a high spatiotemporal resolution, starting from low and moderate Reynolds numbers. The time-dependent evolution of the mean flow dynamics reveals that internal flows, during and after a rapid increase in the flow rate, experience four unambiguous transient stages: inertial, pre-transition, transition and core relaxation before they reach their final steady-state. The first stage is characterised by a rapid and substantial increment in the viscous forces within the viscous sublayer, together with the frozen behaviour of the existing turbulent eddies. The pre-tran..View full abstract
This work was supported with supercomputing resources provided by the Phoenix HPC service at the University of Adelaide. This research was also undertaken with the assistance of resources provided at the NCI NF through the Computational Merit Allocation Scheme, supported by the Australian Government and the Pawsey Supercomputing Centre, with funding from the Australian Government and the Government of Western Australia. The authors acknowledge the financial support of the Australian Research Council.