Independent component analysis of streamwise velocity fluctuations in turbulent channel flows
Independent component analysis (ICA) is used to study the multiscale localised modes of streamwise velocity fluctuations in turbulent channel flows. ICA aims to decompose signals into independent modes, which may induce spatially localised objects. The height and size are defined to quantify the spa...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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Elsevier
2022-05-01
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| Series: | Theoretical and Applied Mechanics Letters |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2095034922000290 |
| _version_ | 1798019300543430656 |
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| author | Ting Wu Guowei He |
| author_facet | Ting Wu Guowei He |
| author_sort | Ting Wu |
| collection | DOAJ |
| description | Independent component analysis (ICA) is used to study the multiscale localised modes of streamwise velocity fluctuations in turbulent channel flows. ICA aims to decompose signals into independent modes, which may induce spatially localised objects. The height and size are defined to quantify the spatial position and extension of these ICA modes, respectively. In contrast to spatially extended proper orthogonal decomposition (POD) modes, ICA modes are typically localised in space, and the energy of some modes is distributed across the near-wall region. The sizes of ICA modes are multiscale and are approximately proportional to their heights. ICA modes can also help to reconstruct the statistics of turbulence, particularly the third-order moment of velocity fluctuations, which is related to the strongest Reynolds shear-stress-producing events. The results reported in this paper indicate that the ICA method may connect statistical descriptions and structural descriptions of turbulence. |
| first_indexed | 2024-04-11T16:38:30Z |
| format | Article |
| id | doaj.art-9a0b52efd8f04df897da8408622ff820 |
| institution | Directory Open Access Journal |
| issn | 2095-0349 |
| language | English |
| last_indexed | 2024-04-11T16:38:30Z |
| publishDate | 2022-05-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Theoretical and Applied Mechanics Letters |
| spelling | doaj.art-9a0b52efd8f04df897da8408622ff8202022-12-22T04:13:44ZengElsevierTheoretical and Applied Mechanics Letters2095-03492022-05-01124100349Independent component analysis of streamwise velocity fluctuations in turbulent channel flowsTing Wu0Guowei He1The State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China; School of Engineering Sciences, University of Chinese Academy of Sciences, Beijing 100049, ChinaThe State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China; School of Engineering Sciences, University of Chinese Academy of Sciences, Beijing 100049, China; Corresponding author.Independent component analysis (ICA) is used to study the multiscale localised modes of streamwise velocity fluctuations in turbulent channel flows. ICA aims to decompose signals into independent modes, which may induce spatially localised objects. The height and size are defined to quantify the spatial position and extension of these ICA modes, respectively. In contrast to spatially extended proper orthogonal decomposition (POD) modes, ICA modes are typically localised in space, and the energy of some modes is distributed across the near-wall region. The sizes of ICA modes are multiscale and are approximately proportional to their heights. ICA modes can also help to reconstruct the statistics of turbulence, particularly the third-order moment of velocity fluctuations, which is related to the strongest Reynolds shear-stress-producing events. The results reported in this paper indicate that the ICA method may connect statistical descriptions and structural descriptions of turbulence.http://www.sciencedirect.com/science/article/pii/S2095034922000290Independent component analysisTurbulent channel flowProper orthogonal decompositionThird-order momentLocalised modes |
| spellingShingle | Ting Wu Guowei He Independent component analysis of streamwise velocity fluctuations in turbulent channel flows Theoretical and Applied Mechanics Letters Independent component analysis Turbulent channel flow Proper orthogonal decomposition Third-order moment Localised modes |
| title | Independent component analysis of streamwise velocity fluctuations in turbulent channel flows |
| title_full | Independent component analysis of streamwise velocity fluctuations in turbulent channel flows |
| title_fullStr | Independent component analysis of streamwise velocity fluctuations in turbulent channel flows |
| title_full_unstemmed | Independent component analysis of streamwise velocity fluctuations in turbulent channel flows |
| title_short | Independent component analysis of streamwise velocity fluctuations in turbulent channel flows |
| title_sort | independent component analysis of streamwise velocity fluctuations in turbulent channel flows |
| topic | Independent component analysis Turbulent channel flow Proper orthogonal decomposition Third-order moment Localised modes |
| url | http://www.sciencedirect.com/science/article/pii/S2095034922000290 |
| work_keys_str_mv | AT tingwu independentcomponentanalysisofstreamwisevelocityfluctuationsinturbulentchannelflows AT guoweihe independentcomponentanalysisofstreamwisevelocityfluctuationsinturbulentchannelflows |