Impact of precessing vortex core dynamics on the thermoacoustic instabilities in a swirl-stabilized combustor
Impact of precessing vortex core dynamics on the thermoacoustic instabilities in a swirl-stabilized combustor
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旋流稳定燃烧室中进动涡核动力学对热声不稳定性的影响
DOI：
10.1017/jfm.2022.610
复制
发表时间：
2022
影响因子：
3.7
通讯作者：
O'Connor, Jacqueline
中科院分区：
文献类型：
--
作者：
Karmarkar, Ashwini;Gupta, Saarthak;Boxx, Isaac;Hemchandra, Santosh;O'Connor, Jacqueline
旋流中的全局不稳定性可以显著改变旋流稳定火焰的火焰和流动动力学，例如现代燃气涡轮发动机中的火焰。在这项研究中，我们描述了进动涡核（PVC）和热声不稳定性之间的相互作用，前者是整体流体动力不稳定的结果，后者是燃烧室声学和非定常热释放率之间耦合的结果。本研究使用的实验数据来自一个模型燃气轮机燃烧室，该燃烧室采用两个同心旋转空气喷嘴，由一圈燃油喷射器分开，在5巴压力下工作。系统地改变两种流之间的流动分裂，观察非反应和反应条件下流动结构变化对系统动力学的影响。采用高速立体粒子图像测速、OH平面激光诱导荧光和丙酮平面激光诱导荧光分别获得了速度场、火焰和燃料流动行为的信息。采用谱固有正交分解和复杂网络分析方法对驱动系统的主要振荡机制进行了识别和表征。在非反应数据中，PVC在大多数情况下存在，振荡幅度随着通过中心喷嘴的流量增加而增加。在反应数据中，可以看到三种主要模式：两种热声模式和聚氯乙烯模式。我们的研究结果表明，在聚氯乙烯的频率与任何一种热声模式重叠的情况下，热声模式被抑制。结合复杂网络分析和弱非线性理论分析，揭示了热声模态耦合和抑制的机制。
Global instabilities in swirling flows can significantly alter the flame and flow dynamics of swirl-stabilized flames, such as those in modern gas turbine engines. In this study, we characterize the interaction between the precessing vortex core (PVC), which is the consequence of a global hydrodynamic instability, and thermoacoustic instabilities, which are the result of a coupling between combustor acoustics and the unsteady heat release rate. This study is performed using experimental data obtained from a model gas turbine combustor employing two concentric swirling nozzles of air, separated by a ring of fuel injectors, operating at five bar pressure. The flow split between the two streams is systematically varied to observe the impact of flow structure variation on the system dynamics at both non-reacting and reacting conditions. High-speed stereoscopic particle image velocimetry, OH planar laser-induced fluorescence and acetone planar laser-induced fluorescence are used to obtain information about the velocity fields, flame and fuel flow behaviour, respectively. Spectral proper orthogonal decomposition and a complex network analysis are used to identify and characterize the dominant oscillation mechanisms driving the system. In the non-reacting data, a PVC is present in most cases and the amplitude of the oscillation increases with increasing flow through the centre nozzle. In the reacting data, three dominant modes are seen: two thermoacoustic modes and the PVC. Our results show that in the cases where the frequency of the PVC overlaps with either of the thermoacoustic modes, the thermoacoustic modes are suppressed. The complex network analysis coupled with a weakly nonlinear theoretical analysis suggests the mechanisms by which this coupling and suppression of the thermoacoustic mode occur.
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通过主动流量控制激励进动涡核，抑制旋流火焰中的热声不稳定性
影响因子：
1.6
作者：
Lückoff;Oberleithner
通讯作者：
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DOI：
--
发表时间：
2018
期刊：
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影响因子：
29.5
作者：
Guillaume Vignat;D. Durox;S. Candel
通讯作者：
S. Candel
DOI：
10.1115/1.4028206
发表时间：
2014-06
影响因子：
1.5
作者：
K. Manoharan;S. Hemchandra
通讯作者：
K. Manoharan;S. Hemchandra
DOI：
--
发表时间：
2007
期刊：
影响因子：
--
作者：
F. Martinelli;A. Olivani;A. Coghe
通讯作者：
A. Coghe