Urban Stormwater Modeling with Local Inertial Approximation Form of Shallow Water Equations: A Comparative Study
浅水方程局部惯性近似形式的城市雨水建模：一个比较研究
浅水方程式の局所慣性近似形式による都市雨水モデリング：比較研究
얕은 물 방정식의 국부 관성 근사 형태를 사용한 도시 우수 모델링: 비교 연구
Modelado de aguas pluviales urbanas con forma de aproximación inercial local de ecuaciones de aguas poco profundas: un estudio comparativo
Modélisation des eaux pluviales urbaines avec approximation inertielle locale des équations des eaux peu profondes : une étude comparative
Моделирование городских ливневых стоков с помощью локальной инерционной аппроксимационной формы уравнений мелкой воды: сравнительное исследование
¹ School of Civil Engineering and Transportation, South China University of Technology, Guangzhou, 510640, China
中国 广州 华南理工大学土木与交通学院
² State Key Laboratory of Subtropical Building Science, School of Civil Engineering and Transportation, South China University of Technology, Guangzhou, 510640, China
中国 广州 华南理工大学土木与交通学院 亚热带建筑科学国家重点实验室
³ Guangdong Engineering Technology Research Center of Safety and Greenization for Water Conservancy Project, Guangzhou, 510640, China
中国 广州 广东省水运工程设计与绿色施工工程技术研究中心
International Journal of Disaster Risk Science, 18 October 2021
Abstract
This study focused on the performance and limitations of the local inertial approximation form model (LIM) of the shallow water equations (SWEs) when applied in urban flood modeling. A numerical scheme of the LIM equations was created using finite volume method with a first-order spatiotemporal Roe Riemann solver. A simplified urban stormwater model (SUSM) considering surface and underground dual drainage system was constructed based on LIM and the US Environmental Protection Agency Storm Water Management Model.
Moreover, a complete urban stormwater model (USM) based on the SWEs with the same solution algorithm was used as the evaluation benchmark. Numerical results of the SUSM and USM in a highly urbanized area under four rainfall return periods were analyzed and compared.
The results reveal that the performance of the SUSM is highly consistent with that of the USM but with an improvement in computational efficiency of approximately 140%. In terms of the accuracy of the model, the SUSM slightly underestimates the water depth and velocity and is less accurate when dealing with supercritical flow in urban stormwater flood modeling. Overall, the SUSM can produce comparable results to USM with higher computational efficiency, which provides a simplified and alternative method for urban flood modeling.
