NUMERICAL STUDY OF OIL SPILL IN THE PATOS LAGOON UNDER FLOOD AND EBB CONDITIONS
Bruno Vasconcellos Lopes1; Phelype Haron Oleinik1; Caroline Barbosa Monteiro1; Douglas Vieira da Silva1; Wiliam Correa Marques1; Ricardo Cardoso Guimarães1; Thaísa Beloti Trombetta1
1 Universidade Federal do Rio Grande
doi:10.20906/CPS/CILAMCE2017-0900
Resumo
Facing the impossibility to completely eradicate the environmental hazards caused by oil spills, mainly in areas where there are periodic oil shipments in tankers, it is crucial the establishment of action protocols against such accidents. In this context, given the potential risks involving the Southern Brazilian Shelf, the focus of this study is the harbor region of Rio Grande, Rio Grande do Sul. The ECOS (Easy Coupling Oil System) model was used to simulate oil spills under different environmental conditions simulated by the hydrodynamic model TELEMAC3D. The oil spill model ECOS uses a Lagrangian approach to simulate the behavior of oil particles subject to the three-dimensional hydrodynamics. This work sought to identify the main forces controlling the movement of the oil slicks and the simulated period consisted of an year of averaged hydrodynamic conditions from 2003 to 2015. The computational domain comprises the Patos Lagoon, the harbor area of Rio Grande and the Southern Brazilian Shelf. For the oil spill simulation eight distinct events were defined considering both flood and ebb conditions in the estuarine region of the Patos Lagoon. The starting point of the oil spills is the Transpetro harbor terminal and due to the averaging of the hydrodynamic conditions from 2003 to 2015, an attenuation of the variability of the currents and winds was observed. Also, due to the river discharge and dominance of north quadrant winds, the most common is the ebb scenario. The oil spill simulations showed that in ebb conditions, the oil slick movement is mainly ruled by the currents, moving towards the outflow. After a few hours the wind action makes the slick move towards the margins of the waterway. The flood conditions, on the other hand, show that the oil slick drifts to the interior of the estuary, following the dominant currents and the local winds.
Palavras-chave: Numerical simulation ; Hydrodynamics ; Oil spill ; Patos Lagoon ; Estuarine region