摆动河槽水动力稳定性特征分析

发布时间：2018-03-31 15:17

本文选题：河槽摆动　切入点：槽道流动　出处：《力学学报》2017年02期

【摘要】：河流形态与水动力结构息息相关,形态约束水动力结构,水动力结构则通过泥沙运动进一步塑造形态,在自然界河流中形成一对辩证互馈关系.天然河流形态形式多样,大致可以分为顺直、微弯、分叉和散乱游荡几种类型,其中微弯及多个弯曲构成的河型为河流动力演化中最重要的一环.多个弯曲构成的河型可用正弦派生曲线来描述,它也是天然河流主槽与水动力结构复杂相互作用的结果.作为探讨这一过程的力学作用机理,构建摆动槽道并研究槽道摆动与其内部流动结构的互馈关系,既是流体力学研究的热点内容,也是目前河流动力过程研究的基础内容.在此重点讨论这一互馈关系前一部分,即水流对摆动边界的响应.文中建立了随体坐标系下摆动河槽与内部水流动力响应理论模型,通过给定摆动弯曲槽道的不同特征参数,研究讨论了正弦派生型摆动边界下的槽道水流动力稳定性特征,明确了弯曲槽道摆动对其内部主流及扰动水流结构的影响,确定弯曲槽道摆动波数、摆动频率对扰动流发展影响的相应参数定量关系,得到了槽道弯曲度和摆动特征对其内部水流不同尺度扰动影响的阈值选择性范围.
[Abstract]:The form of the river is closely related to the hydrodynamic structure, which is constrained by the form of the hydrodynamic structure, and the hydrodynamic structure is further molded by the sediment movement, forming a pair of dialectical mutual feed relations in the natural rivers. The forms of the natural rivers are varied. It can be roughly divided into straight, slightly curved, branched, and scattered types, in which the river type consisting of microbends and multiple bends is the most important link in the dynamic evolution of rivers. The river patterns formed by multiple bends can be described by sinusoidal derivative curves. It is also the result of complex interaction between the main channel of natural river and the hydrodynamic structure. As a mechanism of mechanical action of this process, the oscillating channel is constructed and the interfeed relationship between the channel swing and its internal flow structure is studied. It is not only a hot topic of fluid mechanics research, but also a basic content of river dynamic process research. In this paper, a theoretical model of the dynamic response of the oscillating channel and the internal flow in the accompanying coordinate system is established, and the different characteristic parameters of the channel are given. In this paper, the dynamic stability characteristics of channel flow under sinusoidal derivative boundary are studied, and the influence of bend channel swing on its internal mainstream and disturbed flow structure is clarified, and the waviness number of curved channel wobble is determined. The quantitative relationship of the influence of oscillating frequency on the development of disturbance flow is obtained, and the threshold selectivity range of the influence of channel curvature and wobble characteristics on the disturbance of different scales of the internal flow is obtained.
【作者单位】：天津大学水利工程仿真与安全国家重点实验室;天津大学建筑工程学院;
【基金】：国家自然科学基金项目(41576093,51279124,51321065) 天津大学水利工程仿真与安全国家重点实验室基金(HESS-1606)资助
【分类号】：O352

【相似文献】