Author(s): Yexuan Sun; Peng Hu
Linked Author(s):
Keywords: Rainfall-flooding simulation 1D-2D model coupling GPU acceleration The LTS method
Abstract: Urban flood prediction and risk assessment require advanced modeling techniques to efficiently simulate surface runoff and drainage processes. This study introduces a 1D-2D coupled hydrodynamic model for urban flood simulation, characterized by bidirectional coupling between surface and network modules. A GPU-accelerated and LTS-based (LTS: local time step) finite volume shallow water model is adopted for rainfall-runoff simulations. The drainage network model utilizes a 1D TPA pipe model and an innovative two-dimensional junction calculation method. An important innovation is the implementation of a local-time-stepping (LTS) method, which enhances computational efficiency by allowing cell-specific time step updates, outperforming traditional global minimum time step approaches. Validated through five typical examples, a satisfactory agreement is obtained between simulation results and the available measured data for experimental scenarios, indicating that the model can well simulate flood processes. Implementing the LTS method brings considerable additional improvements over the GPU-acceleration. The quantification of its acceleration efficiency will be detailed in subsequent work.
Year: 2025