长江科学院院报 ›› 2014, Vol. 31 ›› Issue (9): 1-5.DOI: 10.3969/j.issn.1001-5485.2014.09.001

• 江湖泥沙与治理 •    下一篇

180°弯曲水槽内床面冲淤演化过程数值模拟

赵丹禄1,邢岩2,3,艾丛芳2   

  1. 1.天津大学 仁爱学院建筑工程系,天津 301636;
    2.大连理工大学 水利工程学院,大连 116024;
    3.长江科学院 水力学研究所,武汉 430010
  • 收稿日期:2014-03-31 修回日期:2014-09-04 出版日期:2014-09-01 发布日期:2014-09-04
  • 作者简介:赵丹禄(1986-),女,辽宁朝阳人,助教,硕士,研究方向为计算水动力学,(电话)15822229447(电子信箱)zdl20906189@163.com。

Numerical Modeling of Bed Evolution in 180° Bending Flume

ZHAO Dan-lu1, XING Yan2,3, AI Cong-fang2   

  1. 1.Department of Architectural Engineering, Ren’ai College of Tianjin University, Tianjin 301636, China;
    2.School of Hydraulic Engineering, Dalian University of Technology, Dalian 116024,China;
    3.Hydraulics Department, Yangtze River Scientific Research Institute, Wuhan 430010, China
  • Received:2014-03-31 Revised:2014-09-04 Online:2014-09-01 Published:2014-09-04

摘要: 为准确掌握180°弯曲水槽内床面冲淤特征及其演化过程,采用基于非结构化三角形网格的三维流动和地形冲淤数值模型对180°弯曲水槽内床面的冲淤演化过程进行复演。运用标准k-ε紊流模型和显式2步投影方法求解RANS方程,推移质输沙率选取VanRijn输沙公式计算,对于二次流强度较强、横向坡度对输沙方向影响较大的强弯曲水槽,采用方便实用的Engelund方法计算横向底坡所引起的输沙方向的偏移,同时对河床变形所引起的河床临界起动切应力变化进行修正及对流动和地形冲淤相同时间步模拟非恒定的河床冲淤演化过程。与试验测量结果对比显示数值模型对强弯曲水槽冲淤特征有较好的模拟效果;Engelund方法对计算输沙方向偏移角度具有明显的改进;模型同样也具备复演内床面非恒定冲淤演化过程的能力。

关键词: 弯曲水槽, 河床冲淤, 二次流, 横向底坡, 非结构化网格

Abstract: A three-dimensional numerical model based on unstructured triangle grids was used for predicting the flow and time variation of bed deformation in a 180° channel bend. The standard turbulence closed model and explicit project method were employed to solve the RANS equations. The bed load transport quantity was determined with the Van Rijn formula. For a strong secondary flow and the influence of transverse bed slope on the direction of lateral bed load sediment in sharp channel bend, the simple Engelund model was employed to compute the deviation of the sediment transport. Moreover, the critical bed shear stress of incipient motion was also corrected according to the method advanced by Van Rijn. A full set of unsteady flow and bed deformation process within a same time step was predicted. The predicted bed deformation over time was compared with data from a physical model study and good agreement was found.

Key words: channel bend, alluvial channels, secondary flow, transverse slope, unstructured grid

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