This chapter describes the interaction between tsunami bore and cylindrical structure with physical experimental method and 3D – numerical simulations. Several cases were conducted to gain more understanding on the effect of the weir existence as the protective structure. Cylindrical weir with various dimension, e.g. diameter and height, was subjected to interact with various bore height.
Analytical equation, based on Fukui in 1963, was introduced to provides the time series of bore fluid velocities. The governing equations are continuity and momentum equations, with the use of VOF to track the air-water cell. Meanwhile, the experiment were performed on open channel flume with the division gate that separated the upper stream of deep water with down stream of calm shallow water. Tsunami was generated by instantly pulling the division gate, therefore the bore type tsunami wave can be propagate to the dike area.
Both numerical and experimental confirmed that the existence of cylindrical weir delay the arrival of tsunami inundation on the cylindrical structure. The velocity and wave pressure at the bottom sections reduced significantly as the wave loss its energy after hitting the dike. However, the weir attributes, i.e. diameter and height, and wave surface level played important role to determine the magnitude of wave velocity and pressures.
Book Title : Hydrodynamics – Theory and Model
DOI : 10.5772/37032
The manuscript can be download from http://www.intechopen.com/books/hydrodynamics-theory-and-model/study-on-the-interaction-between-tsunami-bore-and-cylindrical-structure-with-weir