洪水数值模拟的三维动态可视化方法

摘要

针对洪水淹没的灾害评估与应急决策管理等问题,本文结合GIS技术与Mike21软件,设计了基于Mike21计算数据的GIS洪水淹没三维动态可视化方法.基于GIS构建研究区段数字地形,建立Mike21二维洪水数学模型,确定糙率与边界条件;模拟典型工况下的来洪情况,计算洪水淹没范围、历时、水深、水位和流速等要素;通过可视化数据的提取与建筑物实体参数化建模,对研究区域三维场景融合,并采用空间数据库与属性数据库相互调用机制,实现淹没过程的动态模拟与实时信息查询.以依兰航电枢纽区段为例,设计开发了依兰航电枢纽区段洪水淹没三维动态可视化系统,能够较好地将Mike21数值模拟结果与GIS的数字地形模型进行耦合,实现洪水淹没三维可视化,为研究区段防洪决策提供数据参考.%To solve challenges such as risk assessments of flood disasters and the emergency decision -making man-agement, this paper combines the GIS technology and Mike 21 software to design GIS flood inundation three-dimen-sional dynamic visualization methods based on calculated data from Mike 21.The digital terrain was established based on the GIS, and a two-dimensional flood mathematical model was built using Mike 21.The roughness and boundary conditions were subsequently confirmed.Flood situations with typical working conditions were simulated , and factors such as flood inundated areas , duration, water depth, water levels, and velocity were calculated. Three-dimensional scenes were implemented by the integration of extracted visual data and a parametric modeling of the building.By adopting the interaction mechanism between spatial database and attribute database , a dynamic simulation of the inundation process and real-time information query were actualized.A three-dimensional dynamic visualization system for flood inundation in Yilan Navigation and Power Junction was designed and developed , which better integrates the Mike21 numerical results with the GIS digital terrain model.This can serve as reference data for the flood controlled decision-making policy in research.