Characteristics of cylindrical flame acceleration in outward expansion
Characteristics of cylindrical flame acceleration in outward expansion
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圆柱火焰向外膨胀的加速特性
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
R. Fursenko
中科院分区：
文献类型：
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作者：
K. Pan;R. Fursenko
本文用火焰跟踪数值方法和直接计算Sivashinsky方程的方法研究了圆柱形火焰的向外传播。火焰速度通过局部曲率经由马克斯坦长度l来修改，该马克斯坦长度以某种方式将复杂的物理化学效应分组并且可以与系统压力单调相关。火焰被发现加速在一个普遍的配置文件作为时间的函数，这是不敏感的初始扰动后，达到自相似制度。加速的程度可以通过幂律的指数来量化，幂律近似于平均火焰半径对时间的依赖性。结果表明，增长指数不随l的变化而变化，但随未燃气体与已燃气体的密度比q的增大而增大。进一步讨论了各种拟合方法，并根据分形分析找到了满足形式关系的合适的拟合方法。因此，指数的多样性，这是补充…
We have studied the outward propagation of a cylindrical flame by means of a flame-tracking numerical method and direct computation of the Sivashinsky equation. The flame speed is modified by the local curvature, via a Markstein length l, that somehow groups the complicated physiochemical effects and can be monotonically relevant to the system pressure. The flame is found to accelerate in a universal profile as a function of time, which is insensitive to initial perturbations after a self-similar regime is reached. The extent of acceleration can be quantified by an exponent of a power law that approximates the dependency of the average flame radius on time. It is shown that the growth exponent is invariant with respect to l while it increases with the density ratio between the unburned and burned gases (q). Furthermore, various fitting approaches are discussed and the proper one is found to satisfy the formal relation according to the fractal analysis. Therefore the diversity of the exponent that was supp...