The wake flow past an axisymmetric body of revolution at a diameter-based Reynolds number
The dynamics of coherent structures in a turbulent wake past a sphere at Re= 3700
The turbulent wake flow past a sphere at ReD= 3700 is investigated via Direct Numerical Simulation (DNS). The characteristic motions in the wake flow, such as vortex shedding and bubble pumping are identified by the probes placed in the near wake with a dominating frequency of St= fu∞/D= 0.22 and 0.004, respectively. The modal analysis is conducted in the wake area using Proper Orthogonal Decomposition (POD) and Dynamic Mode Decomposition (DMD). The vortex shedding and bubble pumping motions are also captured by the modal analysis. The results from POD and DMD show comparable patterns of both characteristic motions. For the bubble pumping motion, the dominating frequency of the corresponding POD mode is St= 0.004, while the DMD mode that is directly related to the separation bubble has the frequency of St= 0.009.
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- PAR ID:
- 10388151
- Publisher / Repository:
- Twelfth International Symposium on Turbulence and Shear Flow Phenomena
- Date Published:
- Journal Name:
- Turbulence and shear flow phenomena
- Volume:
- 2022
- ISSN:
- 2642-0554
- Page Range / eLocation ID:
- 246
- Format(s):
- Medium: X
- Location:
- Osaka, Japan
- Sponsoring Org:
- National Science Foundation
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$Re=u_{\infty }D/\nu =5000$ $St=fD/u_{\infty }=0.27$ $St=0.02$ $St=0.002$ $0.005$ $St=0.005$ -
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