Author(s): Alok Kumar; Gourabananda Pahar

Linked Author(s):

Keywords: SWE; Urban flood; Dynamic and Local variants

Abstract: Depth-average modelling of flood inundation in urban regions is a computationally exhaustive task due to the fine length-scale involved in various parameters such as building spacing, street networks, etc. In recent years, macroscopic modelling of inundation through porous Shallow Water Equations (SWEs) has gained traction. Fluid flow through porous media experiences additional resistance due to the presence of solid skeletal structures. A similar analogy may be used to model urban flood through resistance exerted by buildings along with water storage, preferential paths to alleviate the computational power requirement. A novel single set of depth-integrated conservation laws has been employed to simulate the flow within and outside porous media (i. e., buildings). Three major variants of depth-averaged formulations (dynamic, local, and diffusive wave models) are generally utilized to model inundation through pure SWEs based on different components of acceleration. The first two variants are hyperbolic in nature, and in the present study, these models have been evaluated in urban flood inundation. These systems are resolved through an explicit augmented approximate Riemann solver with a regular finite volume method under variable topography and transition of wet/ dry zones. A few representative test-cases have been simulated to showcase multiple facets of the developed frameworks in urban flooding scenarios. The results obtained from the Local Inertia Model show potential applicability to real-life scenarios with suitable modifications due to minimal convective acceleration present in urban flood dynamics.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p0354-cd

Year: 2023