基于HYSWMM的LID与传统模式下雨水管网对比

以深圳市光明新区光明北片区为研究区域,采用鸿业暴雨排水及低影响开发系统(HYSWMM)模型模拟不同降雨条件下低影响开发(LID)模式的雨水管网运行情况,从径流系数、管网排水能力、管道充满度、节点水深、径流峰值、峰现时间等方面分析LID对雨水管网运行状态的影响。结果表明,对于重现期≤10年的2 h短历时降雨,LID设施的加入对雨水径流具有削减作用,与传统开发模式相比,LID模式下区域径流系数由0.53~0.67降低至0.42~0.56,排水能力提升约10%,管网排放口总出流量峰值降低9.9%~15.9%,节点最大水深降低0.09~0.5 m,充满度最大降低0.22,峰现时间最大可延迟3 min;对于重现期为50年的24 h长历时降雨,LID模式下管网排放口总出流量峰值相比传统开发模式几乎无变化,LID模式在极端暴雨情况下对雨水管网运行状态的影响微弱。

Comparison of Stormwater Pipe Network between LID Mode and Traditional Mode Based on HYSWMM

Operation of stormwater pipe network in low impact development(LID)mode in northern area of Guangming District,Shenzhen at different rainfall conditions was simulated by using HYSWMM,and the influence of LID on the operation of stormwater pipe network was analyzed from the aspects of runoff coefficient,drainage capacity of pipe network,depth ratio,node water depth,runoff peak and peak time.For 2 hours short-duration rainfall with a return period less than 10 years,the addition of LID facilities could reduce stormwater runoff.Compared with traditional mode,regional runoff coefficient decreased from 0.53-0.67 to 0.42-0.56,drainage capacity increased by about 10%,the peak discharge of pipe network outlet decreased by 9.9%-15.9%,the maximum water depth of the node decreased by 0.09-0.5 m,the depth ratio decreased by 0.22 at most,and the peak time was prolonged by 3 minutes.For the 24 hours long-duration rainfall with a return period of 50 years,the peak discharge of pipe network outlet in LID mode was almost unchanged compared with that in the traditional mode,and the influence of LID mode on the operation of stormwater pipe network in extreme storm was weak.