基于水气两相流理论的降雨入渗强度调控方法研究  

Research on Regulation Method of Rainfall Infiltration Intensity Based on Water Gas Two-phase Flow Theory

作　　者：蔡文婧 童富果 薛松[1,2] 李华翔 CAI Wen-jing;TONG Fu-guo;XUE Song;LI Hua-xiang(Hubei Key Laboratory of Hydropower Engineering Construction and Management,China Three Gorges University,Yichang 443002,China;College of Water Hydraulic and Environmental Engineering,China Three Gorges University,Yichang 443002,China)

机构地区：[1]三峡大学湖北省水电工程施工与管理重点实验室,湖北宜昌443002 [2]三峡大学水利与环境学院,湖北宜昌443002

出　　处：《水电能源科学》2024年第2期30-33,98,共5页Water Resources and Power

基　　金：国家自然科学基金项目(51939004);国家自然科学基金青年基金项目(52209135)。

摘　　要：降雨入渗强度是海绵城市建设中的关键指标,入渗强度受土体渗透性和驱动力的联合控制,但以往多关注前者,而较少研究驱动力的调控方法。因此,结合土柱降雨入渗模型试验和数值模拟,探究孔隙气对雨水入渗的驱动效应。通过对试验模型底部进行抽气、注气调控土体内部气压力,发现雨水入渗强度对孔隙气压力具有显著依赖性;底部注气增压时,气压力梯度与入渗方向相反,阻滞雨水入渗;而抽气减压时,其与入渗方向相同,驱动雨水入渗。通过模拟底边界不同气压条件的入渗过程,发现在抽气减压条件下入渗强度与底边界气压力呈线性关系。因此,改变孔隙气压力能调控雨水入渗,特别是在抽气减压条件下降雨入渗强度明显增大,为海绵城市的建设及城市内涝的治理提供了一种新思路。Rainfall infiltration intensity is a key index in the construction of a sponge city,which is jointly controlled by soil permeability and driving force.In the past,more attention has been paid to the former,but less research has been done on the control method of driving force.In this paper,combined with soil column rainfall infiltration model test and numerical simulation,the driving effect of pore air on rainwater infiltration was explored.By pumping and injecting gas at the bottom of the model to control the internal gas pressure of soil,it is found that the infiltration intensity of rainwater has a significant dependence on the pore gas pressure.When the bottom gas injection is pressurized,the gas pressure gradient is opposite to the infiltration direction,which blocks the infiltration of rainwater.When pumping air and reducing pressure,it is the same direction as the infiltration,driving rainwater infiltration.Furthermore,by simulating the infiltration process under different pressure conditions at the bottom boundary,the relationship between the infiltration intensity and the gas pressure at the bottom boundary is linear.Therefore,changing the pore gas pressure can regulate rainwater infiltration,especially the rainfall infiltration intensity increases significantly under pumping conditions,which provides a new idea for the construction of sponge cities and urban waterlogging control.

关 键 词：孔隙气压力 入渗强度 孔隙气压力梯度 模型试验 数值模拟 

分 类 号：TV139.14[水利工程—水力学及河流动力学] TV223.6