Structure and Dynamic Behavior of Flamelet with Strain as Turbulent Combustion Elementary Process

湍流燃烧基本过程应变小火焰的结构与动态行为

• 批准号: 15360111
• 负责人: KOMIYAMA Masaharu
• 金额: $ 5.57万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15360111/
• 关键词: Flamelet; Dynamic behavior; Extinction; Stretch Rate; Preferential Diffusion; Unsteadiness; Direct Numerical Simulation; Laser Diagnostics; Flamelet; Dynamic behavior; Extinction; Stretch Rate; Preferential Diffusion; Unsteadiness; Direct Numerical Simulation; Laser Diagnostics

The turbulent flame consists of the flamelet that receive the strain, and it is useful to clarify the structure and the dynamic behavior of the flamelet for understanding the structure and characteristics of turbulent flame, and establishing a reasonable analytical technique. Therefore, this research aims by an experiment and a direct numerical analysis to clarify flame structure, the extinction characteristics under the control of the flame strain, the structure and dynamic behavior of the edge flame caused by local extinction, which is related to the positive and negative flame strain rate, curvature effect, preferential diffusion, unsteadiness and locality of strain rate.(1)By the numerical analysis that considers elementary chemical reaction and multi-component diffusion of the opposing-flow laminar diffusion flame that uses hydrogen and the methane as a fuel, the strain rate and the flow are controlled by changing the opposing flow velocity and by injecting a jet locally, the rela … More tion among extinction, the strain rate, and the flow fields was analyzed.(2)The flow velocity fluctuation by the sound excitation was given to the fuel or air for the normal diffusion flame and the inverse-diffusion flame of a central jet flow, the flame with a large-scale vortex was formed, and the interacting behavior of the vortex and the flame was analyzed by two dimensional measurement of the temperature and the OH concentration profiles by the Rayleigh scattering and the laser-induced fluorescence.(3)The influence was computationally analyzed, which the interaction between a flame and a vortex gives on flame structure and extinction. When the fluctuation of fuel velocity relatively is weak and the flame does not result in extinction, the preferential diffusion between species and the Lewis-number effect give a large influence on the temperature characteristic of the flame. When the velocity fluctuation is large, the heat release rate decreases with the process of the chemical non-equilibrium, and it results in extinction. Less

湍流火焰由接收应变的火焰组成，阐明火焰的结构和动态行为是有用的，以理解湍流火焰的结构和特征，并建立合理的分析技术。因此，这项研究的目的是通过实验和直接的数值分析来阐明火焰结构，在控制火焰应变控制下的扩展特征，由局部扩展引起的边缘火焰引起的结构和动态行为，这与正面的和负的火焰应变速率，弯曲率和负相关的曲率效应，优先差异，不稳定性，不稳定性和元素的分析。使用氢气和甲烷作为燃料的相对流层流扩散火焰，应变速率和流程通过改变相对的流速速度并在本地注入相对的流动速度来控制，并在延伸速率中向相对频率进行射击。中央喷气流的反向扩散火焰，形成具有大尺度涡流的火焰，并通过雷利散射的二维测量和OH浓度分析来分析涡流和火焰的相互作用行为，并通过雷利散射和激光引起的液体进行了频率。 扩大。当燃料速度相对于弱和火焰的波动不会导致延伸时，物种和刘易斯数量效应之间的首选扩散会对火焰的温度特征产生很大的影响。当速度波动很大时，热释放速率随着化学非平衡的过程而降低，并导致延伸。较少的