优化曼宁的粗度系数使用1维水力动力学建模在多年生河流系统:一个案例的下纳尔马达盆地,印度
Anurag M Bhargav1, R Suresh2, Mukesh K Tiwari3
1Department of Soil and Water Conservation Engineering, College of Agricultural Engineering and Technology, Dr. Rajendra Prasad Central Agricultural University, Pusa, Samastipur, Bihar, India. anurag_bhargav@yahoo.com.
Environmental monitoring and assessment
|July 17, 2024
概括
优化曼宁的粗度系数 (n) 提高了下纳尔马达盆地洪水预报的准确性. 这增强了河流管理和生态系统保护的努力,以实现可持续的水资源利用.
科学领域:
- 水文学的水文学
- 环境工程 环境工程
- 河流动力学 河流动力学
背景情况:
- 精确的液压建模对于有效的河流管理和洪水风险评估至关重要.
- 下纳尔玛达盆地面临着水资源分配和生态系统保护方面的挑战,原因是复杂的水文动态.
- 曼宁粗度系数 (n) 是液压模型中的一个关键参数,但其精确估计通常具有挑战性.
研究的目的:
- 开发一个强大的方法来优化曼宁在下纳尔玛达盆地.
- 提高液压模型的准确性,以改善洪水预测和河流管理.
- 为永久性河流系统的可持续管理提供可操作的见解.
主要方法:
- 使用HEC-RAS v 6.0.0.开发一个一维的水力动力学模型.
- 分析水位,溪流排放和河流阶段数据.
- 通过使用经验证据和计算建模进行模型校准和验证,优化曼宁的n.
主要成果:
- 开发的模型与2020年事件的观察数据有很强的一致性 (R2=0.83,NSE=0.81,RMSE=0.36).
- 为下纳尔玛达盆地确定了0.03的最佳曼宁n值.
- 在下纳尔玛达盆地的沿海地区经常出现洪水.
结论:
- 优化曼宁的n显著提高了用于洪水预测的液压模型的准确性.
- 这些发现有助于更好地预测水流量和更有效地管理该地区的水资源.
- 这项研究支持可持续的河流管理,降低洪水风险和保护下纳尔玛达盆地和类似河流系统的生态系统.
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