汾河兰村—柴村段潜流带水动力特征研究

季晨龙 李海明 肖瀚 李梦雨 王瑞芬 杨丽霞 张雪丽

摘 要：采用数值模拟方法研究汾河兰村—柴村段的潜流带水动力特征，量化潜水含水层对河流水位瞬时抬升1.5 m的响应幅度与影响距离，计算该条件下河流的侧渗补给强度。结果表明：随着与河岸线垂直距离的增大，潜水响应幅度以及河流的侧渗补给流量、侧渗速度逐渐减小，相同时刻起始点x=0处的侧渗速度为上游<中游<下游，侧渗补给流量为上游>中游>下游;在5～90 d内，各断面潜水响应幅度、侧渗速度、侧渗补给流量在与河岸线距离1 000 m之后从峰值逐渐降为0;潜水响应幅度随时间延长呈增大趋势，距河岸线500 m处90 d潜水响应幅度为0.18～0.25 m;距河岸线20～1 000 m处的侧渗速度与侧渗补给流量在5～30 d达到峰值，之后逐渐降低;相同时刻的影响距离为1—1′上兰村断面最远、2—2′汾河大桥断面与3—3′柴村桥断面相近。

关键词：潜流带;水动力特征;侧渗;汾河兰村—柴村段

中图分类号：P641.2;TV138 文献标志码：A

doi：10.3969/j.issn.1000-1379.2021.05.016

Abstract： Numerical modeling method was used to quantify the hydrodynamic characteristics of the subsurface flow in the Lancun-Chaicun section of the Fenhe River such as its response to an instantaneous rise of 1.5 m of Fenhe River water stage and seepage velocity and flow rate from the Fenhe River to the adjacent phreatic aquifer. The results show that the response range of the phreatic aquifer and the lateral seepage rate decreases gradually with an increasing distance to the riparian line. Lateral seepage velocity in x=0 at the same time is upstreammidstream>downstream. Within 5 to 90 d， the response amplitude and lateral seepage flow rate gradually decrease from the peak value to zero after 1 000 m vertical distance from the river riparian line. The response range of phreatic aquifer water level increases with time and the response range of phreatic water reaches 0.18 -0.25 m at 90 days at 500 m away from the river riparian line. The lateral seepage velocity and the flow rate reach the peak value within 5-30 d at the distance of 20-1 000 m from each section to the riparian line of the river and then decrease with time. The influence at the same time is the farthest from section 1-1′ and 2-2′ and 3-3′ are roughly equal.

Key words： subsurface flow; hydrodynamic characteristics; lateral seepage; Lancun-Chaicun section of Fenhe River

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