摘要
在高地下水位地区,地下水会通过管道破损口入渗至排水管道内部,对管网系统的运行造成多种负面影响。通过建立缺陷排水管道地下水入渗三维CFD模型,研究入渗流场的分布机理及影响入渗量的关键因素。首先,为验证数值模型的可靠性,利用物理模型试验结果与数值模拟结果进行了对比分析;其次,对压力场的分析表明,当入渗事件发生时高压力梯度区域只集中在很小的球形区域,在破损口直径为10 mm的情况下,球形区域半径在25 mm左右,增大入口压力并不会改变高压力梯度区域范围,而远离破损口的压力场接近于椭球形;此外,流线分析表明,在多孔介质的影响下水流的行进路线将扩大到管道的四周;最后,利用数值模拟结果对入渗量的解析表达式进行分析,发现当土壤的渗透性较小时孔口的水头损失可以忽略,这与流场的压力分布一致。
In high water table areas, groundwater can infiltrate into the drainage pipes through pipe breaches, causing a variety of negative impacts on the operation of the pipe network system. By establishing a three-dimensional CFD model of groundwater infiltration in defective sewer pipe, the distribution mechanism of the infiltration flow field and the key factors affecting the infiltration volume are investigated. Firstly, to verify the reliability of the numerical model, the experimental results of the physical model are compared with the numerical simulation results. Secondly, the analysis of the pressure field shows that when the infiltration event occurs, the high-pressure gradient area is concentrated in a small spherical area, the radius of the spherical area is about 25 mm for an orifice diameter of 10 mm, and increasing the inlet pressure does not change the range of the high-pressure gradient area, while the pressure field away from the orifice is close to ellipsoidal shape. Also, the flow line analysis shows that the travel route of water flow under the influence of porous media will expand to the surrounding of the pipe. Finally, the analytical expression of the infiltration volume is analyzed using the numerical simulation results and it's found that the head loss at the orifice can be neglected when the permeability of the soil is small.
作者
焦童
郭帅
成浩科
张烨
Jiao Tong;Guo Shuai;Cheng Haoke;Zhang Ye(College of Civil Engineering,Hefei University of Technology,Hefei 230009,China;Yangtze Ecology and Environment Co.Ltd.,Wuhan 430062,China)
出处
《水动力学研究与进展（A辑）》
CSCD
北大核心
2023年第5期747-754,共8页
Chinese Journal of Hydrodynamics
关键词
地下水
排水管道
入渗
数值模拟
破损口
Groundwater
Sewer pipe
Infiltration
Numerical simulation
Orifice
