Excessive flow energy can lead to erosion, necessitating structures designed to dissipate this energy and prevent degradation. This was the primary focus of this research; however, due to the depletion of fossil fuels and the pressing need for sustainable energy solutions, the direction shifted toward mitigating erosion while simultaneously generating electricity rather than merely dissipating energy. Renewable sources such as marine energy have garnered increasing interest. Wave energy, in particular, offers a predictable and environmentally friendly alternative with dual benefits: power generation and coastal protection. This thesis first investigates the hydrodynamics of Multi Horizontal Submerged Jets (MHSJ), their submergence level's impact on energy dissipation, and the resulting bed and side shear stress that contributes to erosion, as presented in Chapter 2. The results indicate that increasing jet submergence increases the Reynolds shear stress and vorticity magnitudes. Furthermore, it was found that greater submergence leads to a 2.2% reduction in maximum bed (floor) shear stress and a 7.2% decrease in side-wall shear stress.
Subsequently, it explores the potential of Wave Energy Converters (WECs) through three distinct studies, detailed in Chapters 3, 4, and 5, addressing both the technical and environmental impacts of wave energy on coastal zones in the Mediterranean and Caspian Seas as well as the energy output of the Wave Dragon WEC. In Chapter 3, the study focuses on the Palm Beach-Azur coastline near Algiers in the Mediterranean Sea, aiming to harness wave energy and reduce coastal erosion. Using historical data and numerical modeling, WECs were assessed for their impact on wave height reduction and sediment deposition. Results show a decrease in wave height by 0.3 meters and an increase in sediment deposition by 0.8 meters with WECs installed, demonstrating that WECs can mitigate coastal erosion while supporting sediment accumulation. This dual functionality of WECs in energy production and coastal protection illustrates their potential environmental and economic advantages in coastal management.
Chapter 4 expands on this by exploring WEC deployment at Astara Port in the Caspian Sea. Using the MIKE21 software, the study evaluates various configurations of WECs, considering factors such as device number, placement, structural arrangement, and orientation relative to wave direction. The configurations examined include two device counts (11 and 13), three placement options (north, front, and south of the port), linear and staggered arrangements, and two orientations (facing northeast and southeast). Findings show that 13 staggered WECs facing the dominant wave direction (northeast) achieve the highest wave height reduction, lowering significant wave height (Hs) by 23–25% under typical conditions and up to 36.26% during storm events. A linear arrangement proved most effective in coastal defense, providing 47.88% boundary protection during storms. Sediment management analysis revealed that a 13-device, linear configuration facing northeast induced the highest sediment accumulation at 0.1231 m over one year, while a staggered 11-device southeast configuration showed minimal sediment buildup at 0.0358 m, underscoring the role of strategic WEC placement in reducing sedimentation near harbor entrances.
Chapter 5 investigates the Wave Dragon as a floating overtopping WEC device for its energy output and structural resilience under various wave conditions using Flow3D modeling. Based on year-long real-time wave data from a buoy, the Wave Dragon’s performance was analyzed across four-wave height scenarios (1.5, 2.5, 3.5, and 4.5 meters). Results demonstrate a significant increase in energy output with wave height, yielding 16.03, 25.52, 31.45, and 56.5 MWh per month, respectively. Additionally, increased wave height resulted in higher pressure on the WEC, with Flow3D simulations indicating that pressure load rose from 2.97 × 10⁵ N at 1.5m to 1.95 × 10⁶ N at 4.5m, approximately a 6.5-fold increase. These findings highlight the scalability of energy output and the structural demands on WECs in high-wave conditions.
These studies, presented in Chapters 3, 4, and 5, underscore the viability of WECs in sustainable energy production and coastal defense. Through comprehensive modeling and scenario analysis, this thesis confirms WECs as a promising sustainable energy and environmental preservation solution in marine contexts.
| Date | 7 Jul 2025 |
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| Original language | American English |
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| Awarding Institution | - École de technologie supérieure
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| Supervisor | Adrian Ilinca (Supervisor) |
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