Experiments on Inundation in Urban Area by a River Water Flooding and Their Analyses

Abstract

Hydraulic physical model experiments concerning the inundation by river water in Kyoto City are carried out to clarify the characteristics of the behavior of flooding water on a complicated city area. The physical model scale is 1/100 and it is a non-distorted model. The model can make allowance for the intrusion of flooding water into underground space. Flooding processes were simulated by using a numerical model that incorporated the finite volume method and unstructured meshes. The flooded area and depth of water in case of no intrusion of flooded water into underground space were reasonably well evaluated by this method, while in case of intrusion of water into underground space calculated results were not well evaluated. The reason is that the drop flow equation was used to estimate the discharge into underground space and that the entrances into underground space were not taken into account reasonably.The suitable equation for evaluating the discharge into underground space must be developed and also the unstructured mesh of entrances must be constituted reasonably.Key Words: flood disaster in urban cities, inundation due to river flood, hydraulic physical model experiment, inundation in underground space, numerical simulation, Kyoto City