湍流中的多尺度结构及其相对运动  

Multi-scaling Structures and Their Relative Motions in Turbulent Flow

作　　者：姜楠[1] 杨宇[1] 

机构地区：[1]天津大学力学系,天津300072

出　　处：《科学技术与工程》2006年第20期3254-3258,共5页Science Technology and Engineering

基　　金：国家自然科学基金(10472081)(10232020)项目联合资助

摘　　要：基于湍流局部多尺度结构物理背景,指出了湍流场与完全随机场的本质区别在于湍流场中流体微团的运动不是完全随机的,湍流场中存在不同尺度的结构,湍流中流体微团的运动受所属流动结构的制约。提出了局部平均速度结构函数的概念以描述一定尺度湍流结构的纵向伸缩变形及其相对运动,并通过实验验证了湍流中基于一定尺度的局部结构平均概念的速度结构函数与子波变换的一致性。Based on the physical difference between turbulent field and in turbulent field is put forward, background of local multi-scaling structures in turbulence, the essential fully random field is that fluid multi-seating particles＇ motion does not be fully random structure being there, and the restriction coming from flowing structure to fluid particles in turbulent field. Furthermore, the velocity structure function based on the concept of local average, which describes two adjacent turbulent structures＇ relative motion at certain scale is put forward also. The idea, given in Kolmogorov＇s theory, instantaneous energy dissipation e being modified by the method of local average （coarse-grained） at certain scale inside turbulent structure is developed. And then the coincidence between velocity structure function based on local structure average and wavelet coefficients is verified respectively in experiment method.

关 键 词：湍流 多尺度结构 间歇性 局部平均 速度结构函数 

分 类 号：O357[理学—流体力学]