Modal diagnostics and nonlinear interaction mechanisms of supersonic jets based on TBOS
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摘要:
针对高马赫数喷流中主导扰动结构难以识别、声源远场辐射机制模糊与非线性交互路径缺乏量化等问题,提出了一种融合了层析重建技术的背景定向纹影(TBOS)实验、密度-压力层析反演、POD模态分解、复模态构建与非线性交互张量分析的多物理场模态识别框架。该方法以马赫数为1.26与1.53两种典型啸音工况为例,通过TBOS技术层析重建轴对称流场密度与压力结构,揭示剪切层与激波的耦合演化过程。构建复模态场并量化主导波长,发现高马赫数下,主导波长增大17%,明确表征剪切层-激波驱动下声波远场辐射结构的有序化。POD频谱主频与理论模型吻合度达99.7%,验证声反馈路径的存在。此外,还引入了Hilbert变换与三模态能量转移张量,发现主模态锁频结构由1-2协同转向1-3强耦合,反馈路径由集中单通道向多模态并联扩散演化,揭示了高马赫喷流中主导模态体系重构与多尺度能量协同调制机制。研究利用单相机投影,结合TBOS可视化技术,建立了“结构识别-传播提取-非线性交互”三层耦合路径,一定程度上突破了传统POD难以辨析主瓣声源演化的瓶颈,为啸音控制、喷流调制与远场辐射建模提供了一种范式与技术支撑。
Abstract:To address the challenges of unclear identification of dominant disturbance structures, ambiguous far-field radiation mechanisms of sound sources, and the lack of quantification for nonlinear interaction paths in high-Mach-number jet flows, a multiphysics modal identification framework integrating tomography-integrated Background-Oriented Schlieren (TBOS) experiments, density-pressure tomographic inversion, Proper Orthogonal Decomposition (POD), complex mode construction, and nonlinear interaction tensor analysis was proposed. Taking Mach number of 1.26 and 1.53 screeching jet conditions as typical cases, the framework tomographically reconstructed the axisymmetric flow field’s density and pressure structures via TBOS, revealing the coupling evolution process between shear layers and shock cells. By constructing the complex mode fields and quantifying the dominant wavelength, it was found that at higher Mach numbers, the dominant wavelength increased by 17%, which explicitly characterized the ordering of far-field acoustic radiation structures induced by shear-shock coupling. The dominant frequencies extracted from POD spectra matched theoretical models with 99.7% accuracy, validating the existence of acoustic feedback paths. Furthermore, Hilbert transform and triadic modal energy transfer tensors revealed that as the Mach number increased, the phase-locking structure of dominant modes transitted from Mode 1-2 coordination to strong Mode 1-3 coupling, accompanied by a shift in energy transport from concentrated single-path feedback to multi-modal distributed interaction. This revealed the reconstruction of dominant modal systems and multi-scale energy cooperative modulation mechanisms in high-Mach-number jets. Utilizing single-camera projection combined with TBOS visualization technology, a three-layer coupling path “structural identification-propagation extraction-nonlinear interaction analysis” was establishes which overcame the limitation of conventional POD to some extent in resolving the evolution of main-lobe acoustic sources. This framework can provide a paradigm and technical support for screech mode identification, jet modulation, and far-field acoustic modeling in supersonic flows.
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表 1 试验系统参数设置
Table 1. Experimental system parameter settings
参数 设置 Zd(背景平面到流场中心的距离)/mm 1900 Zb(背景平面到相机镜头的距离)/mm 3150 帧率/Hz 10000 分辨率/(像素×像素) 1024 ×1024 快门速度/s 1/ 10000 电子背景点分布范围/(mm×mm) 810× 1070 表 2 不同工况下流场总压与总温
Table 2. Total pressure and temperature of the flow field
工况 总压/Pa 总温/K Ma=1.26 252 297 Ma=1.53 356 298 -
[1] SHENG Juan, LI Xiangru, WANG Yitao, et al. Screech in transient supersonic jets[J]. Physics of Fluids, 2022, 34(9): 096102. doi: 10.1063/5.0102992 [2] TAM C K W. Supersonic jet noise[J]. Annual Review of Fluid Mechanics, 27: 17-43. [3] 武鹏, 高军辉. 喷管间距对双喷流啸音影响的实验[J]. 航空动力学报, 2018, 33(1): 124-130. WU Peng, GAO Junhui. Experiment of the effect of nozzle spacing on twin-jet screech tones[J]. Journal of Aerospace Power, 2018, 33(1): 124-130. (in ChineseWU Peng, GAO Junhui. Experiment of the effect of nozzle spacing on twin-jet screech tones[J]. Journal of Aerospace Power, 2018, 33(1): 124-130. (in Chinese) [4] TAM C K W. Computational aeroacoustics - issues and methods[J]. AIAA Journal, 1995, 33(10): 1788-1796. doi: 10.2514/3.12728 [5] LI Hu, LUO Yong, HAN Shuaibin, et al. The source localization and dynamical evolution of axisymmetric screech modes in underexpanded supersonic jets[J]. Aerospace Science and Technology, 2023, 140: 108427. doi: 10.1016/j.ast.2023.108427 [6] EDGINGTON-MITCHELL D. Aeroacoustic resonance and self-excitation in screeching and impinging supersonic jets: a review[J]. International Journal of Aeroacoustics, 2019, 18(2/3): 118-188. [7] LI Xiangru, ZHANG Xiwen, HAO Pengfei, et al. Acoustic feedback loops for screech tones of underexpanded free round jets at different modes[J]. Journal of Fluid Mechanics, 2020, 902: A17. doi: 10.1017/jfm.2020.436 [8] EDGINGTON-MITCHELL D, HONNERY D R, SORIA J. The underexpanded jet Mach disk and its associated shear layer[J]. Physics of Fluids, 2014, 26(9): 096101. doi: 10.1063/1.4894741 [9] CHEN Lanjian, ZHOU Jian, NIE Xiaoming, et al. Measurement range expansion of single-beam Laser Doppler velocimeter based on a focusing transmitter[J]. Optik, 2023, 272: 170383. doi: 10.1016/j.ijleo.2022.170383 [10] RAFFEL M, WILLERT C E, SCARANO F, et al. Particle image velocimetry: a practical guide[M]. 3rd ed. Cham, Switzerland: Springer, 2018. [11] GOJON R, BOGEY C. Numerical study of the flow and the near acoustic fields of an underexpanded round free jet generating two screech tones[J]. International Journal of Aeroacoustics, 2017, 16(7/8): 603-625. [12] SETTLES G, COVERT E. Schlieren and Shadowgraph Techniques: Visualizing Phenomena in Transport Media[J]. Applied Mechanics Reviews, 2002, 55(4): B76-B77. [13] RICHARD H, RAFFEL M. Principle and applications of the background oriented schlieren (BOS) method[J]. Measurement Science and Technology, 2001, 12(9): 1576-1585. doi: 10.1088/0957-0233/12/9/325 [14] RAMANAH D, RAGHUNATH S, MEE D J, et al. Background oriented schlieren for flow visualisation in hypersonic impulse facilities[J]. Shock Waves, 2007, 17(1): 65-70. [15] VENKATAKRISHNAN L, MEIER G E A. Density measurements using the background oriented schlieren technique[J]. Experiments in Fluids, 2004, 37(2): 237-247. doi: 10.1007/s00348-004-0807-1 [16] TAN D J, EDGINGTON-MITCHELL D, HONNERY D. Measurement of density in axisymmetric jets using a novel background-oriented schlieren (BOS) technique[J]. Experiments in Fluids, 2015, 56(11): 204. doi: 10.1007/s00348-015-2076-6 [17] 高磊, 许东. 基于背景纹影技术的随机介质折射率场测量[J]. 航空动力学报, 2017, 32(11): 2653-2658. GAO Lei, XU Dong. Refractive index field measurement of random medium based on background oriented schlieren[J]. Journal of Aerospace Power, 2017, 32(11): 2653-2658. (in ChineseGAO Lei, XU Dong. Refractive index field measurement of random medium based on background oriented schlieren[J]. Journal of Aerospace Power, 2017, 32(11): 2653-2658. (in Chinese) [18] JIA Tong, LI Jiawei, WU Jie, et al. Tomographic background-oriented schlieren for axisymmetric and weakly non-axisymmetric supersonic jets[J]. Symmetry, 2024, 16(5): 596. doi: 10.3390/sym16050596 [19] ADRIAN R J. Twenty years of particle image velocimetry[J]. Experiments in fluids, 2005, 39(2): 159-169. doi: 10.1007/s00348-005-0991-7 [20] EDGINGTON-MITCHELL D, WANG Tianye, NOGUEIRA P, et al. Waves in screeching jets[J]. Journal of Fluid Mechanics, 2021, 913: A7. doi: 10.1017/jfm.2020.1175 [21] AGRAWAL A K, ALBERS B W, GRIFFIN D W. Abel inversion of deflectometric measurements in dynamic flows[J]. Applied Optics, 1999, 38(15): 3394-3398. doi: 10.1364/AO.38.003394 [22] MA Shuiliang, GAO Hongming, WU Lin. Modified Fourier-Hankel method based on analysis of errors in Abel inversion using Fourier transform techniques[J]. Applied Optics, 2008, 47(9): 1350-1357. doi: 10.1364/AO.47.001350 [23] DASCH C J. One-dimensional tomography: a comparison of Abel, onion-peeling, and filtered backprojection methods[J]. Applied Optics, 1992, 31(8): 1146-1152. doi: 10.1364/AO.31.001146 [24] CHEHOUANI H, FAGRICH M. Adaptation of the Fourier–Hankel method for deflection tomographic reconstruction of axisymmetric field[J]. Applied Optics, 2013, 52(3): 439-448. doi: 10.1364/AO.52.000439 [25] TAIRA K, BRUNTON S L, DAWSON S T M, et al. Modal analysis of fluid flows: an overview[J]. AIAA Journal, 2017, 55(12): 4013-4041. doi: 10.2514/1.J056060 [26] GAO J H, LI X D. A multi-mode screech frequency prediction formula for circular supersonic jets[J]. The Journal of the Acoustical Society of America, 2010, 127(3): 1251-1257. doi: 10.1121/1.3291001 [27] PACK D C. A note on prandtl’s formula for the wave-length of a supersonic gas jet[J]. The Quarterly Journal of Mechanics and Applied Mathematics, 1950, 3(2): 173-181. doi: 10.1093/qjmam/3.2.173 -

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