NUMERICAL ANALYSIS OF INUNDATION FLOW DUE TO HEAVY RAINFALL IN THE SHIRAKAWA RIVER ON JULY, 2012

Abstract

 In July, 2012, local heavy rainfall severe caused flooding in the Kyushu area, Kumamoto prefecture, mainly within Shirakawa River. This study looks into behavior through numerical simulations a runoff model and a 2-D inundation flow model is proposed. The surveys show that the flood was caused by the heavy rainfall in a short period. The mathematical model could express the inundation process. To calculate numerical simulation, the fine mesh ground date is modeled by using the LP data and the house map. The simulation results are show good agreement with the field survey data and some interviews. According to numerical analysis distributions of water depth, flow velocity and momentum flux was revealed.