Numerical and experimental performance evaluation of an Eppler 420–based horizontal-axis hydrokinetic turbine for low-velocity river applications
DOI:
https://doi.org/10.58712/jerel.v5i1.202Keywords:
renewable energy, hydrokinetic turbine, Eppler 420, diffuser-augmentedAbstract
Small-scale hydrokinetic turbines offer a viable solution for harnessing renewable energy from low-velocity rivers and canals, particularly in developing countries such as the Philippines, where a large portion of hydropower potential remains untapped. However, limited studies have experimentally validated the performance of airfoil-based propeller hydrokinetic turbines optimized for shallow, low-speed water streams. This study addresses this gap by designing, simulating, fabricating, and experimentally evaluating a horizontal-axis propeller hydrokinetic turbine based on the Eppler 420 airfoil. A combined Computational Fluid Dynamics (CFD) and field-testing approach was employed to optimize blade geometry, tip speed ratio, and diffuser configuration for a turbine with a swept area of 0.18 m² operating at stream velocities of 0.7–1.3 m/s. CFD results indicate that the venturi-type diffuser increased the inlet water velocity by an average of 62%, resulting in a simulated shaft power increase from 56 W for the bare turbine to 70 W for the diffuser-augmented configuration. Field experiments conducted in a local river validated these trends, achieving a maximum measured shaft power of 65 W at 1.3 m/s with a corresponding power coefficient of approximately 0.30. The close agreement between simulated and experimental results confirms the suitability of the Eppler 420 airfoil for low-velocity hydrokinetic applications and demonstrates the effectiveness of diffuser augmentation. The findings provide practical design guidance and experimental validation for efficient small-scale hydrokinetic turbine deployment in shallow inland water streams.
Downloads
References
Aguilar, J., Rubio-Clemente, A., Velasquez, L., & Chica, E. (2019). Design and optimization of a multi-element hydrofoil for a horizontal-axis hydrokinetic turbine. Energies, 12(24). https://doi.org/10.3390/en12244679
Anyi, M., & Kirke, B. (2011). Hydrokinetic turbine blades: Design and local construction techniques for remote communities. Energy for Sustainable Development, 15(3). https://doi.org/10.1016/j.esd.2011.06.003
Brasil Junior, A. C. P., Mendes, R. C. F., Wirrig, T., Noguera, R., & Oliveira, T. F. (2019). On the design of propeller hydrokinetic turbines: the effect of the number of blades. Journal of the Brazilian Society of Mechanical Sciences and Engineering, 41(6). https://doi.org/10.1007/s40430-019-1753-4
Dincer, I., & Ezzat, M. F. (2018). 3.4 Renewable Energy Production. In Comprehensive Energy Systems (pp. 126–207). Elsevier. https://doi.org/10.1016/B978-0-12-809597-3.00310-2
Gilbert, B. L., & Foreman, K. M. (1982). Experiments With a Diffuser-Augmented Model Wind Turbine. American Society of Mechanical Engineers (Paper).
Hazim, S., El Ouatouati, A., Taha Janan, M., & Ghennioui, A. (2020). Performance of a hydrokinetic turbine using a theoretical approach. Energy Reports, 6. https://doi.org/10.1016/j.egyr.2019.08.062
Ibrahim, W. I., Mohamed, M. R., Ismail, R. M. T. R., Leung, P. K., Xing, W. W., & Shah, A. A. (2021). Hydrokinetic energy harnessing technologies: A review. Energy Reports, 7, 2021–2042. https://doi.org/10.1016/J.EGYR.2021.04.003
Ileberi, G. R., & Li, P. (2023). Integrating Hydrokinetic Energy into Hybrid Renewable Energy System: Optimal Design and Comparative Analysis. Energies, 16(8). https://doi.org/10.3390/en16083403
Karalekas, P., Kowalski, G. J., & Lovelace, E. (2013). Modeling hydrokinetic turbine performance in the Mississippi river. Marine Technology Society Journal, 47(4). https://doi.org/10.4031/MTSJ.47.4.21
Kelvin Edem Bassey. (2023). Hydrokinetic Energy Devices: Studying devices that generate power from flowing water without dams. Engineering Science & Technology Journal, 4(2). https://doi.org/10.51594/estj.v4i2.1285
Lamas Galdo, M. I., Rodríguez García, J. de D., Couce Casanova, A., Blanco Damota, J., Caccia, C. G., Rebollido Lorenzo, J. M., & Telmo Miranda, J. (2024). Enhanced Performance of a Hydrokinetic Turbine through a Biomimetic Design. Journal of Marine Science and Engineering, 12(8), 1312. https://doi.org/10.3390/jmse12081312
Ngcukayitobi, M. (2026). Comparative modelling of reaction and impulse turbines using ANN, ANFIS, and PSO-enhanced neural networks. Discover Applied Sciences, 8(1). https://doi.org/10.1007/s42452-025-08100-z
Puertas-Frías, C. M., Willson, C. S., & García-Salaberri, P. A. (2022). Design and economic analysis of a hydrokinetic turbine for household applications. Renewable Energy, 199. https://doi.org/10.1016/j.renene.2022.08.155
Riglin, J., Schleicher, W. C., & Oztekin, A. (2014). Diffuser optimization for a micro-hydrokinetic turbine. ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE), 7. https://doi.org/10.1115/IMECE2014-37304
Saini, G., & Saini, R. P. (2020). Study of installations of hydrokinetic turbines and their environmental effects. AIP Conference Proceedings, 2273. https://doi.org/10.1063/5.0024338
Torrefranca, I., Otadoy, R. E., & Tongco, A. (2022). Incorporating Landscape Dynamics in Small-Scale Hydropower Site Location Using a GIS and Spatial Analysis Tool: The Case of Bohol, Central Philippines. Energies, 15(3). https://doi.org/10.3390/en15031130
Velásquez, L., Rengifo, J., Saldarriaga, A., Rubio-Clemente, A., & Chica, E. (2025). Optimization of Vertical-Axis Hydrokinetic Turbines: Study of Various Geometric Configurations Using the Response Surface Methodology and Multi-Criteria Decision Matrices. Processes, 13(7). https://doi.org/10.3390/pr13071950
