Abstract
A numerical prediction model of the flood-inundation flows with accuracy and high-speed calculation performance was developed. The governing equations applied the combined non-uniform flow equation under the river flows and linear inundation flows equation under the inundation flows in order to calculate rapidly. Inasmuch as high-speed calculation performance may decrease calculation accuracy, the optimized boundary conditions of the river flow were applied and numerical grids of the inundation flow were implemented topography-fitting grid as a new approximation method for the topography. The developed model reproduced most past floods quite accurately and can calculate very rapidly even by PC. Further more, the effects of flood-fighting activities such as levee protection activity were evaluated by the coupled the numerical model with GIS, the evaluation system can also support the levee protection activity.
