Mapping the residual tidal ellipse from Vung Tau–Bac Lieu, Viet Nam by using a numerical model in curvilinear coordinate

Abstract

Tidal currents are often the dominant source of current variability and play an important role in shaping coastal bottom topography. In this paper, the authors applied a hydraulic model in curvilinear coordinates to calculate 4 main tidal constituents, namely K1, O1, M2 and S2 in a region from Vung Tau-Bac Lieu, Viet Nam. The hydraulic model with the two-dimensional orthogonal curvilinear grid has the advantage of increasing the accuracy of the results at the domain boundary. The numerical method of this model derives from the solution of the Reynolds system of equations averaged over depths in the curvilinear coordinate systems. The model verification is implemented based on the equilibrium of the tidal currents of energy. The result of this model is used to map ellipse constituents and help understand more about the tidal deposition from Vung Tau to Bac Lieu, Viet Nam. The results recorded that the residual tidal ellipse M2 from Vung Tau-Bac Lieu, the greatest ellipses are M2, followed by the tidal constituents K1, O1 and S2. This rotation of the ellipse is almost the same with clockwise.

Integration of a numerical model in curvilinear coordinates with sand mining component for bottom morphology simulation

“…The equations that govern the system in curvilinear coordinates are derived from the Reynolds equation, which was originally formulated in Cartesian coordinate [10], as represented by equation (1).…”

“…The bed load continuity equation in the curvilinear coordinate system is described as equation (10).…”

The barotropic simulation of coastal current in Soc Trang derived from a hydraulic model in curvilinear coordinates

“…A calculating grid was constructed using an orthogonal curved grid format, comprising 130×155 cells. The grid size varied between 150 meters and 300 meters, with dx and dy representing the cell dimensions (Figure 1) [31].…”

“…The governing equations in the curvilinear coordinates (HyCCM Model) are constructed based on the Reynolds equation depth-integrated 2D in Cartesian coordinates [31]. In the 2D model, the vertical velocity component is so small that it is ignored, and the pressure is approximated as the hydrostatic pressure distribution.…”

“…This study utilized a numerical model to simulate the coastal current in the Soc Trang area, considering the influential factors of wind and tides on waves. The model employed in this study was developed by [31] and is based on the depth-integrated 2D Reynolds equation in Cartesian coordinates. This model serves as a fundamental tool for assessing and managing coastal protection and risk reduction measures in the region.…”