Development of a Numerical Modeling of the Flow in an Overtopping Device with Coupled Savonius Turbine

Year 2024, Volume: 4 Issue: 2, 37 - 47, 30.12.2024

Elizaldo Dos Santos , Vinicius Heitmann Avila , Rafael Gonçalves Jaifer Martins Emanuel Estrada Liércio Isoldi Luiz Rocha

Abstract

The study of wave energy conversion (WEC) technologies has been growing, with an emphasis on the overtopping device. Its operation is based on a ramp that directs wave water into an elevated reservoir. The accumulated water flows through a low-head tur-bine, generating electricity. This study proposes to develop a complete computational model to simulate a wave channel containing an overtopping device with a Savonius-type turbine inserted in the device's outlet duct. This study deals with the computa-tional modeling of a multiphase (air and water), turbulent, incompressible flow with constant thermo-physical properties, generated by the movement of numerical ocean waves. Verification/validation studies were conducted to guarantee the reliability of the separated models: i) flow in overtopping device without turbine, ii) flow over a free Savonius turbine. After this step, the two models are coupled and results showed that the coupling was successful, allowing the observation of the flow behavior in the complete model. Despite that, the computational model still needs adjustments to the turbine rotation and outlet channel geometry.

Keywords

Overtopping Device, Savonius Turbine, Sea Wave Energy, Numerical Simulation

Project Number

CNPq: 132159/2023-6, 309648/2021-1, 307791/2019-0, 308396/2021-9, 403408/2023-7; ANP: 2024/12385-9

Thanks

The author V. H. Avila thanks CNPq for the master's scholarship (Process: 132159/2023-6) and ANP for the post-doctoral scholarship (Process: 2024/12385-9). The authors L. A. Isoldi, L. A. O. Rocha and E. D. dos Santos thank CNPq for the re-search productivity grant (Processes: 309648/2021-1, 307791/2019-0, 308396/2021-9). The authors would like to thank CNPq for financial support under CNPq/MCTI Call No. 10/2023 - Universal (Process: 403408/2023-7).

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