A review of the study on coherent structures in turbulence by the clustering method

DONG Siwei; CHENG Chen; CHEN Jianqiang; YUAN Xianxu; LI Weipeng

doi:10.6052/1000-0992-20-032

Volume 51 Issue 4

Nov. 2021

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Dong S W, Cheng C, Chen J Q, Yuan X X, Li W P. A review of the study on coherent structures in turbulence by the clustering method. Advances in Mechanics, 2021, 51(4): 792-830 doi: 10.6052/1000-0992-20-032

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Dong S W, Cheng C, Chen J Q, Yuan X X, Li W P. A review of the study on coherent structures in turbulence by the clustering method. Advances in Mechanics, 2021, 51(4): 792-830 doi: 10.6052/1000-0992-20-032

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A review of the study on coherent structures in turbulence by the clustering method

doi: 10.6052/1000-0992-20-032

1.
State Key Lab. Aero., China Aero. R&D Center, Mianyang 621000, Sichuan, China
2.
School of Aeronautics and Astronautics, Shanghai Jiao Tong University, Shanghai 200240, China

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Corresponding author: yuanxianxu@cardc.cn
Received Date: 2020-12-02
Accepted Date: 2021-04-06

Available Online: 2021-04-19

Publish Date: 2021-11-26

Abstract

Abstract

The intrinsic randomness of turbulence requires that the study of coherent structures has to be from the statistical point of view. The data-based clustering method is a powerful tool to realize the deep integration of coherent structures and statistics. It makes each continuous region, i.e., an individual structure, as a statistical sample. In addition, the spatial-temporal tracking method based on the spatial overlap of individual structure between consecutive snapshots makes the evolution of individual structure during its lifetime also as a statistical sample. Thus, both the kinematics and dynamics of coherent structures can be statistically described. We reviewed the history of this method and introduced the progress on Reynolds stress structures, velocity streaks, and cascades with emphasis. These results suggest that the clustering method extraordinarily extended our understanding of turbulence compared with the traditional point-wise statistics. Further prospects are also provided for future research.
- clustering method,
- coherent structures,
- wall-attached eddy,
- energy cascade,
- spatial-temporal evolution

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References(130)

References

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