Numerical Simulation of Urban Flash Flood Experiments Using Adaptive Mesh Refinement and Cut Cell Method

Abstract

Two-dimensional shallow water model based on the cut cell and the adaptive mesh refinement techniques is presented in this paper. These two mesh generation methods are combined to facilitate modeling of complex geometries. By using dynamically adaptive mesh, the model can achieve high resolution efficiently at the interface where flow changes rapidly. The HLLC Reimann solver and the MUSCL method are employed to calculate advection fluxes with numerical stability and precision. The model was applied to simulate the extreme urban flooding experiments performed by the IMPACT (Investigation of Extreme Flood Processes and Uncertainty) project. Simulation results were in good agreement with observed data, and transient flows as well as the impact of building structures on flood waves were calculated with accuracy. The cut cell method eased the model sensitivity to refinement. It can be concluded that the model is applicable to the urban flood simulation in case the effects of sewer and stormwater drainage system on flooding are relatively small like the dam brake.

Urban Flood Simulations with Modified Digital Elevation Model

“…x-and y-directions, i , j S is the source term, and i , j Sc is a term added to balance the second-order scheme. A detailed discussion of the numerical scheme is provided in (An and Yu 2011;An et al 2018).…”

Applicability Evaluation of Flood Inundation Analysis using Quadtree Grid-based Model

“…. Kim(2003) (An and Yu, 2011). Liang et al (2004)은 HLLC(Harten-Lax-van Leer Contact; Fraccarollo and Toro, 1995;Billett and Toro, 1997) (1)…”