Abstract
Separation and vortex motion are key factors limiting the performance improvement of compressors,while the wavy leading-edge can effectively expand the working range of the compressor. This study implements the wavy leading-edge shape on the diffuser cascade,and uses a multi-objective optimization algorithm to construct a wavy leading-edge that significantly reduces the stall point loss at the expense of minimum design point performance. A data mining method,causal network analysis,is used to investigate the flow mechanism of the internal flow field of the dif⁃ fuser cascade with variation in the wavy leading-edge control parameters. The optimization results show that the strength of the leading-edge vortex pairs increases as the amplitude-wave ratio decreases,and that the stall point loss can be significantly reduced at the expense of minimum design point performance with the amplitude-wave ratio range within 0. 05⁃0. 15. The causal network model and flow field analysis verify that,from the vortex motion perspective,the wavy leading-edge generates leading-edge vortex pairs,and the development of the leading-edge vortex pairs weakens that of the channel vortex and trailing-edge vortex flow through different ways;from the separation perspec⁃ tive,the wavy leading-edge weakens the loss caused by the corner region separation by changing the leading-edge airflow inhomogeneity and secondary flow energy and improving the low-energy fluid blockage.
Translated title of the contribution | Flow control mechanism of diffuser cascade with wavy leading⁃edge based on causal network analysis |
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Original language | Chinese (Traditional) |
Article number | 128336 |
Journal | Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica |
Volume | 44 |
Issue number | 19 |
DOIs | |
State | Published - 15 Oct 2023 |