Nonlinear Dynamical Behavior of the River Meandering Process

河流曲流过程的非线性动力行为

• 批准号: 9004646
• 负责人: David Furbish
• 金额: $ 3.6万
• 依托单位: Florida State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-04-01 至 1991-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9004646&HistoricalAwards=false
• 关键词: Nonlinear; Dynamical; Behavior; River; Meandering

Recent mechanically based treatments flow and erosion in bends indicate that river meandering is a highly nonlinear, autocatalytic process wherein diverse, yet self-organized, meander geometries arise independently of variations in flow and erodibility of valley-floor alluvium. The nonlinearity resides in the fact that the channel configuration at each instant evolves from a previous channel state in accordance with mechanical conditions imposed on the flow (and associated boundary stress field) by that previous state. A suitable equation of motion can be written which describes the essentials of this nonlinear behavior. Numerical simulations will be conducted to clarify how the diversity of bend forms that can occur at any instant, and the tendency for certain of these forms to recur over time, are compatible features of meander trains that naturally arise from the nonlinearity of the process.

弯曲中的最新基于机械的治疗流量和侵蚀表明，河流蜿蜒曲折是一种高度非线性的自催化过程，在这种过程中，多样化但自组织的，蜿蜒的几何形状是独立于山谷地板冲积的流动和可侵蚀性的变化而产生的。 非线性源于以下事实：每个即时的通道配置根据先前的机械条件（以及相关的边界应力场）由以前的状态从先前的通道状态演变。 可以写一个合适的运动方程式，描述了这种非线性行为的基本要素。 将进行数值模拟，以阐明如何在任何瞬间发生弯曲形式的多样性，以及这些形式随着时间的流逝的某些形式的趋势，是蜿蜒的列车的兼容特征，这些特征自然来自过程的非线性。