论文标题
动态相干结构的统计非局部性
Statistical Nonlocality of Dynamically Coherent Structures
论文作者
论文摘要
我们引入了一类随机对流问题，可容纳湍流运输分析。流场的统计数据表示为一个连续的时间马尔可夫过程，这种选择捕获了从一个连贯的结构转移到另一个相干结构的直觉概念。我们在不调用近似值的情况下获得了湍流运输算子的封闭形式表达式。我们将湍流传输的经典估计值作为扩散性张量，其成分是速度场的集成自动相关，以期操作员在时空中成为局部性。
We introduce a class of stochastic advection problems amenable to analysis of turbulent transport. The statistics of the flow field are represented as a continuous time Markov process, a choice that captures the intuitive notion of turbulence as moving from one coherent structure to another. We obtain closed form expressions for the turbulent transport operator without invoking approximations. We recover the classical estimate of turbulent transport as a diffusivity tensor, the components of which are the integrated auto-correlation of the velocity field, in the limit that the operator becomes local in space and time.
