On the identification of cross-flow mode in three-dimensional boundary layers
Parametric zones are obtained where the cross-flow instability can be identified as a mode in the three-dimensional boundary layers with the Mach number ranging from 0 to 10. Although the term cross-flow mode is widely used in the investigations on boundary-layer instability, the previous work [Z. L...
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| Format: | Article |
| Language: | English |
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AIP Publishing LLC
2023-01-01
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| Series: | AIP Advances |
| Online Access: | http://dx.doi.org/10.1063/5.0135008 |
| _version_ | 1811172568834506752 |
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| author | Zhiyong Liu |
| author_facet | Zhiyong Liu |
| author_sort | Zhiyong Liu |
| collection | DOAJ |
| description | Parametric zones are obtained where the cross-flow instability can be identified as a mode in the three-dimensional boundary layers with the Mach number ranging from 0 to 10. Although the term cross-flow mode is widely used in the investigations on boundary-layer instability, the previous work [Z. Liu, Phys. Fluids 34, 094110 (2022)] has demonstrated that a cross-flow mode cannot be designated in certain circumstances. The identification of the cross-flow mode is significant not only in the justifiable use of the term but also in judging whether a disturbance is more inclined to a cross-flow type or not. In this work, a criterion is built to identify the cross-flow mode based on the growth-rate peak and disturbance shape. By means of extensive calculations and identifications, parametric zones are presented for the unstable cross-flow mode. It is found that the cross-flow mode cannot be identified at large local sweep or at Mach numbers larger than 1.6. In parametric zones, the cross-flow mode can be distinguished from the Tollmien–Schlichting mode, or identified as the solely dominant mode. Based on the identifications, the maximum growth rates of the cross-flow mode, the Tollmien–Schlichting mode, and the Mack modes in the three-dimensional boundary layers are provided. The dominant mode can be determined at different Mach numbers. The cross-flow mode is revealed to dominate the boundary-layer instability at low Mach numbers. Under large cross-flow strengths, the second mode could not be the dominant mode in the hypersonic boundary layers, which contrasts sharply with the two-dimensional case. |
| first_indexed | 2024-04-10T17:33:32Z |
| format | Article |
| id | doaj.art-73af2af5317b47e9b0218e9403cb6d1a |
| institution | Directory Open Access Journal |
| issn | 2158-3226 |
| language | English |
| last_indexed | 2024-04-10T17:33:32Z |
| publishDate | 2023-01-01 |
| publisher | AIP Publishing LLC |
| record_format | Article |
| series | AIP Advances |
| spelling | doaj.art-73af2af5317b47e9b0218e9403cb6d1a2023-02-03T16:42:07ZengAIP Publishing LLCAIP Advances2158-32262023-01-01131015203015203-1910.1063/5.0135008On the identification of cross-flow mode in three-dimensional boundary layersZhiyong Liu0China Academy of Aerospace Aerodynamics, Beijing 100074, ChinaParametric zones are obtained where the cross-flow instability can be identified as a mode in the three-dimensional boundary layers with the Mach number ranging from 0 to 10. Although the term cross-flow mode is widely used in the investigations on boundary-layer instability, the previous work [Z. Liu, Phys. Fluids 34, 094110 (2022)] has demonstrated that a cross-flow mode cannot be designated in certain circumstances. The identification of the cross-flow mode is significant not only in the justifiable use of the term but also in judging whether a disturbance is more inclined to a cross-flow type or not. In this work, a criterion is built to identify the cross-flow mode based on the growth-rate peak and disturbance shape. By means of extensive calculations and identifications, parametric zones are presented for the unstable cross-flow mode. It is found that the cross-flow mode cannot be identified at large local sweep or at Mach numbers larger than 1.6. In parametric zones, the cross-flow mode can be distinguished from the Tollmien–Schlichting mode, or identified as the solely dominant mode. Based on the identifications, the maximum growth rates of the cross-flow mode, the Tollmien–Schlichting mode, and the Mack modes in the three-dimensional boundary layers are provided. The dominant mode can be determined at different Mach numbers. The cross-flow mode is revealed to dominate the boundary-layer instability at low Mach numbers. Under large cross-flow strengths, the second mode could not be the dominant mode in the hypersonic boundary layers, which contrasts sharply with the two-dimensional case.http://dx.doi.org/10.1063/5.0135008 |
| spellingShingle | Zhiyong Liu On the identification of cross-flow mode in three-dimensional boundary layers AIP Advances |
| title | On the identification of cross-flow mode in three-dimensional boundary layers |
| title_full | On the identification of cross-flow mode in three-dimensional boundary layers |
| title_fullStr | On the identification of cross-flow mode in three-dimensional boundary layers |
| title_full_unstemmed | On the identification of cross-flow mode in three-dimensional boundary layers |
| title_short | On the identification of cross-flow mode in three-dimensional boundary layers |
| title_sort | on the identification of cross flow mode in three dimensional boundary layers |
| url | http://dx.doi.org/10.1063/5.0135008 |
| work_keys_str_mv | AT zhiyongliu ontheidentificationofcrossflowmodeinthreedimensionalboundarylayers |