10:25 AM - 10:40 AM
[14005-09-02] Validation of the numerical simulation method for bores propagating through a permeable resistance in open channel (Proceedings of Symposium on Applied Mechanics)
Keywords:Hydrodynamic force, Bore, Permeable resistance
In order to develop an appropriate numerical method for tsunamis run up in rivers, it is important to reproduce the hydrodynamic forces due to permeable resistance such as vegetation. In this study, two-dimensional calculation for the attenuation of a bore propagates through a vegetations was conducted using the evaluation method for hydrodynamic force that can consider nonuniform flow effects, and the method was validated by comparing it with experimental results. In a straight channel with a group of cylinders, bores were generated by the rapid opening of a gate installed upstream, and the temporal variation of wave height was measured. The conventional calculation using the drag coefficient overestimated the wave height. On the other hand, the calculation results, in which the additional force due to the pressure gradient was taken into account in addition to the drag coefficient, reproduced the energy fluxes of the reflected waves generated by the hydrodynamic force and the bores propagating downstream appropriately, resulting in a good reproduction of the temporal variation of wave height and the longitudinal distribution of maximum wave height.