Author(s): G. Vignoli; M. Toffolon; M. Tubino
Linked Author(s):
Keywords: Tide; Hydrodynamics; Non-linear; Friction; Estuary
Abstract: In this paper we tackle the problem of the role of non-linear terms on the propagation of the tidal wave in prismatic and convergent channels, through a onedimensional formulation of the shallow water momentum and continuity equations. The solution is obtained numerically applying the MacCormack explicit scheme. The above approach allows one to take into account non-linear effects and to compare different formulations for the frictional term. It is shown that a linearized approximation is not suitable to represent adequately the propagation of the tidal wave, in particular when sharp fronts occur. Moreover, the effect on the mean free surface slope of non-linear residual effects associated with the frictional term is investigated. They are related to the different values of flow depth occurring during the ebb and the flood phase. As a result the average water level tends to rise landward, due to the larger dissipation in the ebb phase.
Year: 2003