Abstract
At Re = 3900, Newtonian flow past a circular cylinder exhibits a wake and detached shear layers which have transitioned to turbulence. It is the goal of the present study to investigate the effects which viscoelasticity has on this state and to identify the mechanisms responsible for wake stabilization. It is found through numerical simulations (employing the FENE-P rheological model) that viscoelasticity greatly reduces the amount of turbulence in the wake, reverting it back to a state which qualitatively appears similar to the Newtonian mode B instability which occurs at lower Re. By focusing on the separated shear layers, it is found that viscoelasticity suppresses the formation of the Kelvin-Helmholtz instability which dominates for Newtonian flows, consistent with previous studies of viscoelastic free shear layers. Through this shear layer stabilization, the viscoelastic far wake is then subject to the same instability mechanisms which dominate for Newtonian flows, but at far lower Reynolds numbers. © Copyright Cambridge University Press 2012.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 297-318 |
| Number of pages | 22 |
| Journal | Journal of Fluid Mechanics |
| Volume | 693 |
| DOIs | |
| State | Published - Jan 16 2012 |
| Externally published | Yes |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledgements: The authors would like to acknowledge the Army High Performance Computing Research Center for Agility, Survivability and Informatics, Award No. W911NF-07-2-0027, High Performance Technologies Inc., and Department of the Army (Prime) for partial financial and computational support. In addition, this research has been funded in part by a KAUST research grant under the KAUST-Stanford Academic Excellence Alliance program. Any opinions, findings, and conclusions or recommendations expressed in this paper are those of the authors and do not necessarily reflect the views of the KAUST university. Finally, the authors acknowledge the following award for providing computing resources that have contributed to the research results reported within this paper: MRI-R2: Acquisition of a Hybrid CPU/GPU and Visualization Cluster for Multidisciplinary Studies in Transport Physics with Uncertainty Quantification. This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.