论文标题
在二维剪切流中混合，并平滑波动
Mixing in two-dimensional shear flow with smooth fluctuations
论文作者
论文摘要
通过加剧的搅拌，流量速度混合的混乱变化。本文介绍了在常规剪切流中混合被动标量场的统计特性，并在其背景下随机波动。我们考虑二维流，剪切成分在平滑波动上占主导地位。这种流程应该模拟被动标量混合，例如在以二维湍流或微通道中的弹性湍流中形成的大规模相干涡流中。我们检查了衰减的情况和标量差异连续强迫的情况。在这两种情况下，动态都具有强大的间歇性，可以通过单点矩和我们工作中计算的相关功能来表征。我们介绍了对相关函数的一般定性特性以及在模型框架中获得的某些定量结果，并且随时间相关的波动相关。
Chaotic variations in flow speed up mixing of scalar fields via intensified stirring. This paper addresses the statistical properties of a passive scalar field mixing in a regular shear flow with random fluctuations against its background. We consider two-dimensional flow with shear component dominating over smooth fluctuations. Such flow is supposed to model passive scalar mixing e.g. inside a large-scale coherent vortex forming in two-dimensional turbulence or in elastic turbulence in a micro-channel. We examine both the decaying case and the case of the continuous forcing of the scalar variances. In both cases dynamics possesses strong intermittency, that can be characterized via the single-point moments and correlation functions calculated in our work. We present general qualitative properties of pair correlation function as well as certain quantitative results obtained in the framework of the model with fluctuations that are short correlated in time.
