Multi-layered coarse grid modelling in 2D urban flood simulations
Multi-layered coarse grid modelling in 2D urban flood simulations
复制标题
DOI：
10.1016/j.jhydrol.2012.06.022
复制
发表时间：
2012-11-12
影响因子：
6.4
通讯作者：
Savic, Dragan A.
中科院分区：
文献类型：
--
作者：
Chen, Albert S.;Evans, Barry;Savic, Dragan A.
规则网格通常用于二维洪水建模，因为地形模型的广泛可用性和输入准备所需的预处理较低。尽管计算软件和硬件都取得了进步，但在时间和资源有限的情况下，当应用于大范围的研究区域时，高分辨率洪水模型的计算要求仍然很高。传统的网格粗化方法不仅降低了计算量，而且由于丢失了详细信息而降低了结果的准确性。为了保留影响粗网格内流动传播的关键特征，本文提出并测试的方法在洪水建模中采用多层来反映粗网格单元内由建筑物分隔的单个流道。每一层的单元都有自己的参数（海拔、粗糙度、建筑覆盖率和运输减少因子）来描述自身以及与相邻单元的边界条件。综合案例研究和实际城市区域的测试结果表明，该方法在不增加计算成本的情况下大大提高了粗网格建模的精度。以高分辨率结果为基准，结合UIM模型对所提出的方法进行了测试。将所提出的多层方法应用于任何基于规则网格的二维模型都是简单明了的。爱思唯尔B.V.版权所有
Regular grids are commonly used in 2D flood modelling due to wide availability of terrain models and low pre-processing required for input preparation. Despite advances in both computing software and hardware, high resolution flood modelling remains computationally demanding when applied to a large study area when the available time and resources are limited. Traditional grid coarsening approach may reduce not only the computing demands, but also the accuracy of results due to the loss of detailed information. To keep key features that affect flow propagation within coarse grid, the approach proposed and tested in this paper adopts multiple layers in flood modelling to reflect individual flow paths separated by buildings within a coarse grid cell. The cell in each layer has its own parameters (elevation, roughness, building coverage ratio, and conveyance reduction factors) to describe itself and the conditions at boundaries with neighbourhood cells. Results of tests on the synthetic case study and the real world urban area show that the proposed multi-layered approach greatly improves the accuracy of coarse grid modelling with an insignificant additional computing cost. The proposed approach has been tested in conjunction with the UIM model by taking the high resolution results as the benchmark. The implementation of the proposed multi-layered methodology to any regular grid based 2D model would be straightforward. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.