Free Water Surface Oscillations in a Closed Rectangular Basin with Internal Barriers

Thee enclosed basin has certain natural frequencies of seiche, depending on the geometry of the water boundaries and the bathymetry of water depths. Therefore, the variation in the water surface at a point becomes irregular, as caused by the combination of several natural frequencies, which may be considered as the superposition of sinusoidal frequency components of different amplitude. This paper is mainly concerned with the motion of an incompressible irrotational fluid in a closed rectangular basin with internal impervious barriers. An analytical solution is presented for predicting the characteristic of generated waves in these types of basin. The equations of free water surface oscillations and its boundary conditions are reduced to a system of linear equations, which is solved by applying the small amplitude water wave theory. The flow potential, wave amplitude, flow patterns and the natural period of waves generated in the basin with impervious internal barriers are found, based on the basin geometry. It is shown that the natural period of the basin is strongly dependent on the location of the barriers and the size of the barrier opening.