层分化对水力动力学和混合过程的影响,在中国北部的大不对称汇合处
Cheng Dong1, Minquan Feng1, Haixiao Jing1
1State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an 710048, China.
Journal of contaminant hydrology
|February 28, 2025
概括
河流交汇处的沉积物分层显著改变了流动动态,加速了污染物混合. 这项研究揭示了密度变化如何影响河流液压和污染物运输,缩短混合距离.
科学领域:
- 环境流体动力学 环境流体动力学
- 河流工程 河流工程
- 水质建模水质建模
背景情况:
- 河流交汇的水力动力学受到几何学,流量比和河床形态的影响.
- 由于温度,盐度或沉积物度的分层,越来越多地被认为是融合动态的关键因素.
研究的目的:
- 研究沉积物诱导的分层对流体动力学和污染物混合的影响.
- 通过使用3D数值模型分析黄河与芬河交汇区的影响.
主要方法:
- 使用3D数值模型模拟流量和污染物运输.
- 分析了深度平均流域和二次流动模式.
- 检查了流量大小的变化,剪切层,低速度区域和横截面.
主要成果:
- 沉积物诱导的密度变化影响了水平和垂直流动力学.
- 主流中的高沉积物度导致了分层,支流污染物骑在上面.
- 由于分层造成的二次流量加剧,污染物混合距离缩短了.
结论:
- 沉积物分层显著影响河流合流水力学和污染物混合.
- 分层可以通过增强二次流量来加速污染物分散.
- 这些发现有助于更好地了解河流交汇处污染物运输机制.
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