Numerical simulation of tides, tidal currents and residual currents in the Yellow River estuary,

Abstract

A 3-D Finite-Volume Coastal Ocean Model was applied in the Bohai Sea, especially near the Yellow River estuary, to simulate the tides, tidal currents, residual currents and shear fronts, using unstructured triangular grids. In the case of an accurate simulation of the tides and tidal currents in the Bohai Sea, this article focuses on the Yellow River mouth. The type of tides is irregular semi-diurnal and the type of tidal currents is the reciprocating flow, mostly parallel to the coastline. The tide induced eulerian residual currents are a couple of eddies on each side of the river mouth, with the anticlockwise on the left side and clockwise on the other side, and both of the eddies are enhanced by the Yellow River runoff. Two patterns of shear fronts are identified at the conversion between the flood and ebb tidal phase. The results suggest that the shear fronts be generated in the shallow water because the tidal phase of the coastal area is ahead of the deeper seaward area, then moves seaward and finally disappears 1-2 hours later.