基于斜率校正的小型至中型河流的回流区内最低可航行流量排放的快速计算方法
Jinyang Wang1,2, Dongdong Jia1,3, Xingliang Jiang4,5,6
1Key Laboratory of Port, Waterway and Sedimentation Engineering of Ministry of Transport, Nanjing Hydraulic Research Institute, Nanjing 210029, China.
概括
确定最低航行流量排放 (MNFD) 对受水转移项目影响的水道至关重要. 一种新的快速计算方法显著提高了复杂河流区域MNFD的准确性.
科学领域:
- 水文学的水文学
- 河流工程 河流工程
- 水资源管理 水资源管理
背景情况:
- 最低导航流排放 (MNFD) 对于保持水道尺寸至关重要,特别是在受水转移项目影响的地区.
- 由于地形和下游回流效应之间的复杂相互作用,估计河流回流区的MNFD具有挑战性.
- 关于生态补偿的利益相关者谈判往往使MNFD的确定变得复杂.
研究的目的:
- 开发一个MNFD在河流水区的快速计算程序.
- 提高MNFD估计在受地形变化和回流效应影响的地区的准确性.
- 为水资源管理人员和工程师提供实用工具.
主要方法:
- 用理论分析和数值模拟来开发MNFD计算程序.
- 在曼宁方程中整合了水面斜率校正.
- 一个二维的水力动力学模型被用于验证,使用石川河作为案例研究.
主要成果:
- 与直接应用曼宁方程相比,建议的快速程序显著改善了MNFD估计.
- 对于一个IV类水道,拟议的方法产生了616 m3/s的MNFD,与数值模拟的600 m3/s非常接近.
- 使用新方法,与数值结果的相对偏差从155%减少到3%.
结论:
- 开发的快速计算程序为河流回流区的MNFD估计准确性提供了显著的改进.
- 这种方法为在复杂的河流系统中确定MNFD提供了更可靠和更有效的方法.
- 准确的MNFD确定对于有效的水资源管理和生态补偿策略至关重要.
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