Diffusive dynamics and stochastic models of turbulent axisymmetric wakes
Diffusive dynamics and stochastic models of turbulent axisymmetric wakes
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DOI：
10.1017/jfm.2015.390
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发表时间：
2015-06
影响因子：
3.7
通讯作者：
Georgios Rigas;A. Morgans;Rowan D. Brackston;J. Morrison
中科院分区：
文献类型：
--
作者：
Georgios Rigas;A. Morgans;Rowan D. Brackston;J. Morrison
本文提出了一种模拟方法来再现对称性条件下湍流的实验测量结果。流动是由轴对称体产生的三维尾流。我们表明，湍流尾流的动力学可以同化的非线性二维朗之万方程，其中的确定性部分占破碎的对称性，发生在层流和过渡制度在低雷诺数和随机的一部分，其中占湍流波动。理论和实验结果之间的比较允许模型参数的提取。
A modelling methodology to reproduce the experimental measurements of a turbulent flow in the presence of symmetry is presented. The flow is a three-dimensional wake generated by an axisymmetric body. We show that the dynamics of the turbulent wake flow can be assimilated by a nonlinear two-dimensional Langevin equation, the deterministic part of which accounts for the broken symmetries that occur in the laminar and transitional regimes at low Reynolds numbers and the stochastic part of which accounts for the turbulent fluctuations. Comparison between theoretical and experimental results allows the extraction of the model parameters.