A COMPARISON OF VELOCITY FIELD IN TSUNAMI INUNDATION OVER COASTAL URBAN CITY

Abstract

 In recent years, roughness coefficients and drag coefficients that take into account the geometry of structures have been proposed, but their accuracy has been validated using inundation depths and arrival times, and there have been few studies on detailed velocity fields. In this study, the accuracy of the individual Drag Force Model (iDFM), which treats the structures in the computational grid as drag forces, was verified through the idealized numerical experiments and the replication of tsunami inundation experiments. In both cases, the iDFM reproduced the inundation area well regardless of the resolution. The velocity field was not reproduced well in the areas where localized flow was dominant, such as roads and alleys, suggesting the need to improve the model.