移动降雨时空分布对坡面产流的影响

Investigation of hillslope runoff due to moving storms in flume-scale experiments

降雨的时空分布是影响坡面水文响应的重要因素之一。本文结合实测物理模型实验数据与基于物理概念的数值模型Intergrated Hydrology Model(InHM)研究降雨的时空分布对坡面产流的影响。利用收集到的实测物理模型数据对数值模拟结果进行参数率定、验证后,再分别对均匀与非均匀分布降雨条件下的坡面产流情况进行数值模拟,通过分析两者间的模拟结果的差异,可以定量化地研究降雨时空分布对坡面产流所产生的影响。研究结果表明:均匀空间分布与不均匀空间分布降雨引起的坡面产流存在相当大的差别,由降雨空间分布的不均匀性带来的产流峰值的变化差距可以超过40%;也验证了在降雨移动产生的时间变化下,产流峰值随着移动方向与坡面方向间角度的增大而逐渐减小。

The temporal and spatial distribution of rainfall strongly influences hillslope hydrology responses.In this study,a physical-based hydrologic-response model（known as the Integrated Hydrology Model,or InHM）was used with previous laboratory data to investigate hillslope runoff.The numerical results compared well with the laboratory data in both the calibration and validation phases.The model was then used to simulate the hillslope hydrology response for homogeneous and inhomogeneous rainfall distributions.The modeling results showed significant differences in the hillslope runoff for homogeneous and inhomogeneous rainfall distributions.Inhomogeneous rainfall can increase the peak runoff by more than 40% with the peak runoff decreasing as the angle between the moving storm and hillslope direction increased.