Hydrodynamic study of the Ilha Grande and Sepetiba Bays
Name: Thiago Zamprogno Mordente
Type: MSc dissertation
Publication date: 12/06/2020
Advisor:
Name![]() |
Role |
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Julio Tomás Aquije Chacaltana | Advisor * |
Examining board:
Name![]() |
Role |
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Diogo Costa Buarque | Internal Examiner * |
Julio Tomás Aquije Chacaltana | Advisor * |
Marcos Nicolás Gallo | External Examiner * |
Summary: Hydrodynamics is extremely important for several activities that take place in an
estuary. Additionally, the application of computational fluid dynamics for a better
understanding of the circulation is a recurring practice today. In this context, the
present work aims to use the shallow water equations, resulting from applying the
concept of long wave in the Navier-Stokes equations, with the purpose of evaluating
the hydrodynamics of the estuarine complex of the Ilha Grande and Sepetiba bays, on
the influence of the forcing astronomical tide and wind. In order to identify the
contribution of the wind to the hydrodynamics, 2 scenarios were considered: Scenario
1 using only the astronomical tide as a forcing, and Scenario 2, which used the
astronomical tide and the wind. In the calibration of the simulated results, three
parameters were adjusted: time step, background roughness and wave continuity. For
each scenario, statistical parameters were calculated that indicated Scenario 2 as the
best that fits the measured data. In the results validation of scenario 2, the values of
the statistical parameters found were 0.09m for the Mean Absolute Error (MAE), 0.12m
for the Root Mean Square Error (RMSE) and 0.96 for the Willmotts Index (d). The
results point to a greater sensitivity of the model to wind forcing, mainly in Sepetiba
Bay. Additionally, it was possible to observe that the shape of Sepetiba Bay is capable
of affecting the circulation pattern in its interior. However, it was not possible to observe
the existing cyclonic effect near Ilha Grande. Therefore, modeling considering the tide
and wind as forcing in the two-dimensional model of ADCIRC was not able to represent
the hydrodynamics of the region in a satisfactory way.