可冲刷坡面滚波影响因素的数值模拟研究  

Factors Influenced on the Morphology and Hydrodynamics of Roll Waves in Overland Flow Over Mobile bed

作　　者：李侃禹[1,2] 曹志先[1] 谈广鸣[1] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072 [2]长江航道局,湖北武汉430070

出　　处：《应用基础与工程科学学报》2012年第6期987-993,共7页Journal of Basic Science and Engineering

基　　金：国家自然科学基金项目(50459001)

摘　　要：运用能够模拟可冲刷坡面滚波的一维水沙耦合数学模型,对床面形态起伏、冲淤厚度及含沙量沿程变化等因素对滚波形态的影响进行研究,并比较水沙耦合与非耦合模型数值模拟结果的差异.结果表明床面形态起伏越大,滚波的波幅及周期变化越剧烈,滚波周期与床面形态起伏的对应关系越明显;冲淤厚度对滚波运动特性的直接影响不明显,但河床发生冲淤变化后,床面的起伏形态发生相应变化,进而对滚波的运动特性产生较大影响.水沙耦合与非耦合数学模型相比,滚波形态模拟结果差异较大,因此对坡面起伏明显、水沙输移强度较大的山区坡面流数值模拟应采用能够更好的模拟水沙输移规律的水沙耦合模型.Factors influencing the evolution of roll waves and the associated morphological change were investigated using a one-dimensional coupled numerical model for sediment-laden roll waves over mobile beds in this paper. Those factors included morphological evolution, morphological change depth,longitudinal variation of sediment concentration et al. Comparisons of numerical results between the coupled and the uncoupled mathematical models were also conducted. It was shown by numerical results that the more complex the bed topography was, the greater the variation of the wave amplitude and the wave duration. The morphological change depth had little direct effect on the roll wave＇ s motion characteristic. Nevertheless, morphological change directly complicated the bed topography, leading to the formation of bed form undulation, which inturn affected the roll wave characteristics. In the case of roll wave with intense sediment transport over mountainous complex topography, considerable differences were observed between the coupled and uncoupled models, indicating the necessity of coupled models under these conditions.

关 键 词：滚波 可冲刷坡面 数值模拟 耦合水沙模型 影响因素 

分 类 号：TV131.2[水利工程—水力学及河流动力学]