摘要
30年来,对湍流的研究出现了不少新的研究手段,如大涡模拟、混沌、分叉及相干结构等。但是,目前在湍流机理上最有希望突破的是大尺度相干结构的研究和把大型计算机作为湍流研究工具。本文综述了近年来相干结构研究发展概况,讨论了在相千结构的理论研究方面应该开展的工作。
The significance of turbulence in most natural and technological flows as well as its inherent complexity cannot be overemphasized. Despite dedicated efforts many able scientists over the decades, Turbulence continues to persist one of the least understood arenas of the natural sciences. New ideas and interpretations are highly desirable, but also must be carefully examined. Turbulence research has experienced two revolutions in past decade. The first, rather profound, is the discovery of large-scale coherent structures. The second is the integration of the digital computer as an active component of the turbulence research arsenal.
Purpose of this paper is a statement on the present state of understanding of coherent structures, in particular their spatial details and dynamical singnificance. The definitions or its dynamical implications are discussed. The recent analytical treatments of coherent structures, such as triple and double decompositions, instability of free shear layer or boundary layer, waves, solitons, strange attractor and vortex dynamics, are reviewed and commented. We also briefly discussed some benefits of coherent structures, including the negative production, the mechanism of production of turbulence in shear flow layers and cut-and-connect interaction of coherent structures.
出处
《中国科学基金》
CSCD
1990年第1期29-37,共9页
Bulletin of National Natural Science Foundation of China
