Stochastic geometric properties of scalar interfaces in turbulent jets
Stochastic geometric properties of scalar interfaces in turbulent jets
复制标题
湍流射流中标量界面的随机几何性质
DOI：
10.1063/1.857876
复制
发表时间：
1991
影响因子：
4.6
通讯作者：
P. Dimotakis
中科院分区：
文献类型：
--
作者：
P. Miller;P. Dimotakis
利用激光诱导荧光（LIF）技术对湍流射流中标量界面的行为进行了研究。实验在高施密特数流体（水）中进行，射流中心线上，射流雷诺数范围为1000≤Re≤ 24000。使用标准的一维和二维分形盒计数算法分析了固定x/d时的二维标量数据c（r，t）和固定x/d和r/x时的一维标量数据c（t）。对噪音的处理给予了仔细的处理。还研究了长记录和短记录以及偏离中心线的测量。讨论了阈值对结果的重要影响。在所研究的雷诺数范围内，没有发现常数（幂律）分形维数的证据。另一方面，结果是一致的计算行为的一个简单的随机模型的接口几何。
Experiments were conducted in which the behavior of scalar interfaces in turbulent jets was examined, using laser‐induced fluorescence (LIF) techniques. The experiments were carried out in a high Schmidt number fluid (water), on the jet centerline, over a jet Reynolds number range of 1000≤Re≤24 000. Both two‐dimensional scalar data, c(r,t) at fixed x/d, and one‐dimensional scalar data, c(t) at fixed x/d and r/x, were analyzed using standard one‐ and two‐dimensional fractal box‐counting algorithms. Careful treatment was given to the handling of noise. Both long and short records as well as off‐centerline measurements were also investigated. The important effect of threshold upon the results is discussed. No evidence was found of a constant (power‐law) fractal dimension over the range of Reynolds numbers studied. On the other hand, the results are consistent with the computed behavior of a simple stochastic model of interface geometry.