Large Eddy Simulation of the Sensitivity of Vortex Breakdown and Flame Stabilisation to Axial Forcing
Large Eddy Simulation of the Sensitivity of Vortex Breakdown and Flame Stabilisation to Axial Forcing
复制标题
涡破裂和火焰稳定对轴向力敏感性的大涡模拟
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
C. Duwig
中科院分区：
文献类型：
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作者：
P. Iudiciani;C. Duwig
研究了轴向力对火焰/涡流击穿相互作用的影响，特别关注进动涡核 (PVC)。大涡模拟 (LES) 与描述子网格燃烧的过滤火焰模型一起用于研究在各种频率和振幅下经历质量流量波动的贫预混火焰。平均而言，低于 PVC 特征频率的频率下的强制会将再循环区移动到预混合管中燃烧器的上游，而较高的频率不会相关地影响流量/火焰。借助本征正交分解 (POD)，对中央再循环区 (CRZ) 的动力学进行了详细分析，显示了较低频率的激励如何削弱 PVC 并允许火焰向上游传播。扩展 POD 还用于说明激发循环期间的流动/火焰相互作用。
The effect of axial forcing on the flame/vortex breakdown interaction is studied, with particular focus on the Precessing Vortex Core (PVC). Large Eddy Simulation (LES), together with a filtered flamelet model describing the subgrid combustion, is performed to study a lean premixed flame undergoing mass flow fluctuations in a wide range of frequencies and amplitude. In average, forcing at frequencies lower than the PVC characteristic frequency moves the recirculation zone upstream the combustor in the premixing tube, while higher frequencies do not relevantly affect the flow/flame. With the help of Proper Orthogonal Decomposition (POD) a detailed analysis of the dynamics of the central recirculation zone (CRZ) is performed showing how the excitation at lower frequencies weakens the PVC and allows the flame to propagate upstream. Extended POD is also applied to illustrate the flow/flame interactions during the excitation cycle.