水科学与水工程2008，Vol.1Issue(4)：14-21,8.DOI:10.3882/j.issn.1674-2370.2008.04.002
Numerical algorithm of distributed TOPKAPI model and its application
Numerical algorithm of distributed TOPKAPI model and its application
摘要
Abstract
The TOPKAPI (TOPographic Kinematic APproximation and Integration) model is a physically based rainfall-runoff model derived from the integration in space of the kinematic wave model. In the TOPKAPI model, rainfall-runoff and runoff routing processes are described by three nonlinear reservoir differential equations that are structurally similar and describe different hydrological and hydraulic processes. Equations are integrated over grid cells that describe the geometry of the catchment, leading to a cascade of nonlinear reservoir equations. For the sake of improving the model's computation precision, this paper provides the general form of these equations and describes the solution by means of a numerical algorithm, the variable-step fourth-order Runge-Kutta algorithm. For the purpose of assessing the quality of the comprehensive numerical algorithm, this paper presents a case study application to the Buliu River Basin, which has an area of 3 310 km2, using a DEM (digital elevation model) grid with a resolution of 1 km. The results show that the variable-step fourth-order Runge-Kutta algorithm for nonlinear reservoir equations is a good approximation of subsurface flow in the soil matrix, overland flow over the slopes, and surface flow in the channel network, allowing us to retain the physical properties of the original equations at scales ranging from a few meters to 1 km.关键词
TOPKAPI model/Runge-Kutta algorithm/Buliu River Basin/flood simulationKey words
TOPKAPI model/Runge-Kutta algorithm/Buliu River Basin/flood simulation引用本文复制引用
Deng Peng,Li Zhijia,Liu Zhiyu..Numerical algorithm of distributed TOPKAPI model and its application[J].水科学与水工程,2008,1(4):14-21,8.基金项目
This work was supported by the National Natural Science Foundation of China (Grant No. 50479017) and the Program for Changjiang Scholars and Innovative Research Teams in Universities (Grant No. IRT071). （Grant No. 50479017）
