Conditional Sampling of Turbulence Intensities and Reynolds Stress in Premixed Turbulent Flames
Conditional Sampling of Turbulence Intensities and Reynolds Stress in Premixed Turbulent Flames
复制标题
预混湍流火焰中湍流强度和雷诺应力的条件采样
DOI：
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发表时间：
1984
期刊：
影响因子：
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通讯作者：
R. Cheng
中科院分区：
文献类型：
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作者：
R. Cheng
摘要发展了一种用于预混湍流火焰中湍流强度和雷诺应力条件采样的双色LDA技术。为了在未燃烧的反应物中有条件地取样，使用燃烧和燃烧蒸发的硅油气雾剂作为流动种子。传统的Al_2O_3晶种颗粒用于在火焰中无条件取样。开发了一种条件分析方法，从非条件数据中推导出焚烧产品中的条件数据。在稀乙烯/空气V型火焰中获得的有条件和无条件数据的比较表明，所谓的火焰产生的湍流和火焰刷内雷诺应力的增加主要是由反应物和产物中的间歇性测量引起的。使用火焰湍流的间歇性模型，间歇性的贡献与条件平均速度之间的差异成正比。条件性波动加剧了……
Abstract Abstrac–-A two-color LDA technique has been developed for conditional sampling of turbulence intensity and Reynolds stress in premixed turbulent flame. To sample conditionally in the unburned reactants, silicone oil aerosol which burned and evaporated by combustion is used to seed the flow. Conventional AI2O3 seed particles are used to sample unconditionally through the flame. A conditional analysis method is developed to deduce conditioned data in the burned products from the unconditioned data. Comparison of the conditioned and unconditioned data obtained in a lean ethylene/air v-flame shows that the so-called "flame-generated turbulence" and the increase in Reynolds stress within the flame brush are caused primarily by intermittent measurements in the reactants and in the products. Using an intermittency model for the flame turbulence, the contributions due to intermittency are shown to be proportional to the difference between the conditioned mean velocities. The conditioned fluctuation inten...