Marine resources are outstanding among renewable energy for their wide occurrence and diverse possibilities of exploitation. The tidal resource can be harnessed by the use of both potential (sea level) and kinetic energy (tidal currents). Maranhão coast presents one of the largest tidal ranges and strongest currents on Brazilian coastline, providing a good source of renewable energy. A 3D hydrodynamic model is implemented to numerically simulate the tidal circulation in the Maranhão Gulf so as to examine the tidal behavior and associated energy distribution. Amplitudes and current speeds are substantially increased by the estuary’s geomorphology and the shallow bathymetry. M₂ tidal component presents the highest amplitudes among the tidal constituents, being the most energetic. Spring-neap cycle constitute an important factor in energy assessment due to their significant difference in power density and exchanged water volume between estuary and continental shelf. Maximum current velocities of 3 m s⁻¹ are found around Medo Island, where tidal range can reach nearly 5.5 m. Three potential regions are located within the São Marcos Estuarine Complex, presenting surface velocities ranging from 1 to 2.15 m s⁻¹ and power density as high as 5 kW m⁻². The estuary is long and presents significant variations of tidal phase that allows a geographical disposition of turbines in order to lower the downtime.

中文翻译：

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Maranhão海湾潮汐环流和功率密度分布的数值模拟

海洋资源是可再生能源中的佼佼者，因为其广泛存在且具有多种开发潜力。潮汐资源可以通过利用势能（海平面）和动能（潮流）来利用。Maranhão海岸是巴西海岸线上最大的潮汐范围和最强的洋流之一，提供了可再生能源的良好来源。实现了3D水动力模型，以数值模拟Maranhão海湾的潮汐环流，从而检查潮汐行为和相关的能量分布。入海口的地貌和浅测深法显着提高了振幅和电流速度。中号₂潮汐分量在潮汐分量中呈现出最高的振幅，是最活跃的。春季-春季周期是能量评估的重要因素，因为它们的功率密度和河口与大陆架之间交换的水量存在显着差异。在梅多岛周围发现了3 m s ^-1的最大流速，潮汐范围可以达到近5.5 m。三个潜在区域位于圣马科斯河口综合区内，呈现的速度范围为1至2.15 m s ^-1，功率密度高达5 kW m ^-2。河口很长，潮汐相位变化很大，可以在地理上布置涡轮机，以减少停机时间。