NUMERICAL ANALYSIS ON INUNDATION DUE TO THE SHIN RIVER BREACH CAUSED BY TOKAI HEAVY RAIN

Abstract

The mathematical model which can simulate inundation process in the urban areas due to heavy rain has been developed. The problems of model are to devise the configuration of the grid and to consider buildings, sewage system, streams etc. In this study, the numerical simulation was conducted to reconstruct the Shin-river breach caused by Tokai heavy rain in September 2000. This model employed the ground elevation as the initial condition and the overflow discharge at breach point as the boundary condition. Governing equations are 2-D continuity and momentum equations to simulate urban overland inundation. The result of the numerical simulation was represented by GIS and compared with the field data obtained by the questionnaire. These results indicate the accuracy of this inundation simulation and are helpful in flood management in the future.