Extended scale invariance in the vortices of freely evolving two-dimensional turbulence
Extended scale invariance in the vortices of freely evolving two-dimensional turbulence
复制标题
DOI：
10.1103/physrevfluids.2.114702
复制
发表时间：
2017-11
期刊：
影响因子：
--
通讯作者：
B. H. Burgess;D. Dritschel;R. K. Scott
中科院分区：
文献类型：
--
作者：
B. H. Burgess;D. Dritschel;R. K. Scott
在自由演化的二维湍流中，涡数密度n(A，t)由平均涡旋强度ω2 v(A，t)补偿后，遵循自相似形式n(A，t)/ω2 v(A，t)∼t−2/3A−1。尽管n(A，t)和ω2 v(A，t)的标度不同，但对于不同的初始条件，这种扩展的标度不变行为仍然成立，并确保周转次数[ω2 v(A，t)，T)]−1/2所采用的特征涡间距离与尺度无关。
We report the existence of a self-similar scaling in the vortices of freely evolving twodimensional turbulence: The vortex number density n(A,t) compensated by the mean vortex intensity ω2 v(A,t), where A is vortex area and t is time, follows the self-similar form n(A,t)/ω2 v(A,t) ∼ t−2/3A−1. This extended scale-invariant behavior holds for different initial conditions, despite very different scaling of n(A,t) and ω2 v(A,t) taken separately, and ensures that the number of turnaround times [ω2 v(A,t)] −1/2 taken to cross the characteristic intervortex distance is independent of scale.