We perform global linear stability analysis on low-Re flow past an isolated cylinder with rounded corners. The objective of the present work is to investigate the effect of the cylinder geometry (corner radius) on the stability characteristics of the flow. Our investigation sheds light on new physics that the flow can be stabilized by partially rounding the cylinder in the critical and weakly super-critical flow regimes. The flow is first stabilized and then gradually destabilized as the cylinder varies from square to circular geometry. The sensitivity analysis reveals that the variation of stability is attributed to the different spatial variation trends of the backflow velocity in the near- and far-wake regions for various cylinder geometries. The results from the stability analysis are also verified with those of the direct simulations and very good agreement is achieved.
|Original language||English (US)|
|Journal||Journal of Fluids Engineering|
|State||Published - Sep 1 2017|
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: W. Z. would like to thank the support from NSFC (51536008). The IBM Blue Gene/P Shaheen at KAUST was utilized for the simulations under the KAUST Office of Competitive Research Funds (URF/1/1394-01). The comments from the reviewers are appreciated.