Spectral properties and transport mechanisms of partially chaotic bounded flows in the presence of diffusion.
Spectral properties and transport mechanisms of partially chaotic bounded flows in the presence of diffusion.
复制标题
存在扩散时部分混沌有界流的光谱特性和输运机制。
DOI：
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发表时间：
2004
影响因子：
8.6
通讯作者：
V. Vitacolonna
中科院分区：
文献类型：
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作者：
M. Giona;A. Adrover;S. Cerbelli;V. Vitacolonna
本文分析了在有界域中定义的部分混沌周期流的平流-扩散方程的poincar<s:1>算符的谱性质。对于逐渐消失的小扩散系数（即，对于趋于无穷大的Peclet数），主要特征值Lambda表现出近似于Pe-alpha的缩放Lambda，其中（0,1）中的指数alpha取决于流的全局特性（准周期岛屿的形状，几何形状和对称性）。指数alpha的值是性质上不同输运机制的一个指标，它取决于相应特征函数的局域化性质。
The spectral properties of the Poincaré operator associated with the advection-diffusion equation for partially chaotic periodic flows defined in bounded domains are analyzed in this Letter. For vanishingly small diffusivities (i.e., for the Peclet number tending to infinity) the dominant eigenvalue Lambda exhibits the scaling Lambda approximately Pe-alpha, where the exponent alpha in (0,1) depends on the global property of the flow (shape, geometry, and symmetry of quasiperiodic islands). The value of the exponent alpha is an indicator of qualitatively different transport mechanisms and depends on the localization properties of the corresponding eigenfunctions.