Turbulent Elementary Votrices and New Development in Theory, Predicition, and control of Turbulence

湍流初等涡流及湍流理论、预测和控制的新进展

基本信息

批准号：
12125101
负责人：
KIDA Shigeo
金额：
$ 4.1万
依托单位：
Kyoto University (2003)National Institute for Fusion Science (2000-2002)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research on Priority Areas
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2002
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12125101/
关键词：
Turbulence Elementary Vortex Turbulence Theory Turbulence Prediction Turbulence Control

项目摘要

The elementary vortices are the smallest coherent structures in turbulence. Their physical characteristics and dynamical roles in turbulence have been clarified by the theory, the experiment, and the computer simulation in various kinds of turbulence realized in nature, laboratories, and computers. The elementary vortices exhibit common physical characteristics independent of the kinds of turbulence, that is, a tubular central vortex is surrounded by spiral vortex layers, the diameter and swirl velocity obey the Kolmogorov scaling laws but the length of the vortex extends to the large scales of turbulence, the vortices make groups and are localized in space, and many elementary vortices tend to approach in an anti-parallel manner and enhance the mixing ability. As engineering and practical applications, the large-eddy-simulation model based on the elementary vortices, the active feedback control of the wall turbulence by manipulating the elementary vortices have been developed, and the mechanisms of the enhancement of supersonic mixing combustion by introducing the longitudinal vortices and the generation of tornados as the large-scale coherent vortex have been clarified. Furthermore, the unstable periodic motions (spatio-temporal coherent structure as the skeleton of turbulence) accompanying regeneration of elementary vortices have been discovered in the Couette turbulence. The concept and the dynamics of turbulent elementary vortices established in the present research project shall be useful for the future turbulence research.

基本涡旋是湍流中最小的相干结构。它们在自然界，实验室和计算机中实现的各种湍流中的理论，实验和计算机模拟已经阐明了它们在湍流中的身体特征和动态作用。基本涡流表现出共同的物理特征，与湍流的种类无关，即，管状中央涡流被螺旋涡旋层所包围，直径和漩涡速度遵守kolmogorov的规律，kolmogorov的缩放法则，但涡流的长度延伸到范围的范围，范围均构成了较大的元素，并且均位于湍流中，并且在湍流中构成了许多构图，并构成了许多构图，并构成了许多构图，并构成了许多构图，并构成了许多构图，并延伸到湍流中，并延伸到湍流中。并增强混合能力。作为工程和实际应用，已经开发了基于基本涡流的大涡模拟模型，通过操纵基本涡流对壁湍流的主动反馈控制，以及通过引入纵向涡流和龙卷风的旋转量来加强超音速燃烧的机制。此外，在COUETTE湍流中发现了伴随基本涡流再生的不稳定周期性动作（时空连贯的结构作为湍流的骨骼）。在本研究项目中建立的动荡基本涡流的概念和动力学对于未来的湍流研究非常有用。