基于城市排水过程的内涝高效模拟方法

Simulation of high efficiency urban flood inundation in the drainage process

从实际城市排水过程的角度出发,提出了基于汇水单元概念的城市内涝高效模拟方法.该方法以雨篦子作为出水口来划分汇水单元,进而计算城市地表产汇流、积水深度及分布.同时,引入了当量宽度的概念,实现了明渠与有压流2种状态下管道流量和水位计算方法的统一.基于水量平衡原理,利用雨篦子耦合城市地表与地下管网,并结合孔口耦合管道与河道,构建了地表-管道-河道一体化的求解矩阵.本文将所提出的模拟方法植入成熟的太湖流域模型,并应用常州市城市产汇流与内涝试验基地的监测数据,对该方法的有效性和模型的可靠性进行了评估,以期为城市内涝模拟提供新思路.

The frequent occurrence of extreme rainfall events in recent years has increasingly become a significant issue affecting the economic and social development of China.In this paper we start from the perspective of actual urban drainage processes and propose an efficient simulation method for urban flood inundation based on the concept of catchment units.This method utilizes grate inlets as outlets to delineate catchment units,thereby calculating urban surface runoff,flood inundation depth,and distribution.The concept of equivalent width is introduced to unify the calculation methods for flow rate and water level in open channels and pressurized pipe flow conditions.Based on the principle of water balance,grate inlets are used to couple urban surfaces with underground pipelines,and orifices are used to couple pipes with rivers,thereby constructing an integrated solving matrix for surface-pipe-river systems.This proposed simulation method was incorporated into the mature Taihu Basin Model and applied to monitoring data from the urban runoff and flood inundation experimental site in Changzhou to evaluate the effectiveness of this method and the reliability of this model,aiming to provide new insights for urban flood inundation simulation.