Abstract
There are many flows with submersible large roughness elements in nature. In order to understand these flows, it is important to clarify resistance of the large roughness elements and flow around them. For this purpose, a numerical model together with physical model tests, which can estimate the resistance and the flow, is necessary. In this paper, drag forces acting on submersible large roughness elements were measured directly through experiments. A numerical computation method using a two-dimensional shallow water model which employs the general curvilinear coordinate system is developed and made possible to evaluate the resistance of submersible large roughness elements. The model is applied to simulate flows with a group of submersible large roughness elements and in an urban district, where submersible and non- submersible houses are arbitrarily arranged.
