Influence of Extension Ratio on the Performance of the Modified Savonius Hydrokinetic Turbine
Publication: Journal of Energy Engineering
Volume 149, Issue 6
Abstract
In the present investigation, a modified Savonius hydrokinetic turbine of 0.245 m turbine diameter (), 0.1 overlap ratio, 0.2 shape factor, and 0.002 m blade thickness () has been investigated numerically to study the influence of extension ratio on the performance of the turbine. The effect of vane end extension on the performance of the Savonius hydrokinetic turbine is investigated by numerical simulations. Two-dimensional transient simulations are done with a pressure-based solver by keeping the diameter of the turbine constant. The study is carried out in a finite-volume solver by using unsteady Reynolds Navier-Stokes equations with a shear stress transport turbulence model. The coefficient of torque is considered for the 12th revolution of the turbine for different extension ratios of 0, 0.041, 0.082, 0.122, 0.163, and 0.204. The maximum instantaneous coefficient of torque () is obtained for vane orientations of 100° to 130° and 280° to 310°. The maximum coefficient of power () of the turbine is 0.2441 for an extension ratio of 0.041, which is 15.5% higher than that of the turbine with a zero-extension ratio.
Get full access to this article
View all available purchase options and get full access to this article.
Data Availability Statement
All data and models used during the study appear in the published article.
Acknowledgments
Authors gratefully acknowledge Science and Engineering Research Board (SERB), Department of Science and Technology, Delhi, India for funding through core research grant for this study. The sanction order number is CRG/2020/005420.
References
Abdelaziz, K. R., M. A. A. Nawar, A. Ramadan, Y. A. Attai, and M. H. Mohamed. 2022a. “Performance improvement of a Savonius turbine by using auxiliary blades.” Energy 244 (Apr): 122575. https://doi.org/10.1016/j.energy.2021.122575.
Abdelaziz, K. R., M. A. A. Nawar, A. Ramadan, Y. A. Attai, and M. H. Mohamed. 2022b. “Performance investigation of a Savonius rotor by varying the blade arc angles.” Ocean Eng. 260 (Sep): 112054. https://doi.org/10.1016/j.oceaneng.2022.112054.
Benchikh Le Hocine, A. E., S. Poncet, and J. Lacey. 2020. “Numerical modeling of a Darrieus horizontal axis shallow-water turbine.” J. Energy Eng. 146 (5): 04020050. https://doi.org/10.1061/(ASCE)EY.1943-7897.0000700.
Chemengich, S. J., S. Z. Kassab, and E. R. Lotfy. 2022. “Effect of the variations of the gap flow guides geometry on the Savonius wind turbine performance: 2D and 3D studies.” J. Wind Eng. Ind. Aerodyn. 222 (Mar): 104920. https://doi.org/10.1016/j.jweia.2022.104920.
Chen, W., and X. Sun. 2023. “A comparative study of the influences of leading-edge suction and blowing on the aerodynamic performance of a horizontal-axis wind turbine.” J. Energy Eng. 149 (1): 04022051. https://doi.org/10.1061/JLEED9.EYENG-4583.
Driss, Z., O. Mlayeh, S. Driss, D. Driss, M. Maaloul, and M. S. Abid. 2015. “Study of the bucket design effect on the turbulent flow around unconventional Savonius wind rotors.” Energy 89 (Sep): 708–729. https://doi.org/10.1016/j.energy.2015.06.023.
Eshagh, M., H. Fatahian, and E. Fatahian. 2020. “Performance improvement of a Savonius vertical axis wind turbine using a porous deflector.” Energy Convers. Manage. 220 (Sep): 113062. https://doi.org/10.1016/j.enconman.2020.113062.
Golecha, K., T. I. Eldho, and S. V. Prabhu. 2011. “Influence of the deflector plate on the performance of modified Savonius water turbine.” Appl. Energy 88 (9): 3207–3217. https://doi.org/10.1016/j.apenergy.2011.03.025.
Jafari, M., A. Razavi, and M. Mirhosseini. 2018. “Effect of steady and quasi-unsteady wind on aerodynamic performance of H-rotor vertical axis wind turbines.” J. Energy Eng. 144 (6): 04018065. https://doi.org/10.1061/(ASCE)EY.1943-7897.0000578.
Jeon, K. S., J. I. Jeong, J.-K. Pan, and K.-W. Ryu. 2015. “Effects of end plates with various shapes and sizes on helical Savonius wind turbines.” Renewable Energy 79 (Jul): 167–176. https://doi.org/10.1016/j.renene.2014.11.035.
Kacprzak, K., G. Liskiewicz, and K. Sobczak. 2013. “Numerical investigation of conventional and modified Savonius wind turbines.” Renewable Energy 60 (Dec): 578–585. https://doi.org/10.1016/j.renene.2013.06.009.
Kailash, G., T. I. Eldho, and S. V. Prabhu. 2012. “Performance study of modified Savonius water turbine with two deflector plates.” Int. J. Rotating Mach. 2012 (May): 679247. https://doi.org/10.1155/2012/679247.
Kamoji, M. A., S. B. Kedare, and S. V. Prabhu. 2009. “Experimental investigations on single stage modified Savonius rotor.” Appl. Energy 86 (7–8): 1064–1073. https://doi.org/10.1016/j.apenergy.2008.09.019.
Kuang, L., H. Lei, D. Zhou, Z. Han, Y. Bao, and Y. Zhao. 2021. “Numerical investigation of effects of turbulence intensity on aerodynamic performance for straight-bladed vertical-axis wind turbines.” J. Energy Eng. 147 (1): 04020087. https://doi.org/10.1061/(ASCE)EY.1943-7897.0000740.
Ma, Y., Y. Zhu, A. Zhang, C. Hu, S. Liu, and Z. Li. 2022. “Hydrodynamic performance of vertical axis hydrokinetic turbine based on Taguchi method.” Renewable Energy 186 (Mar): 573–584. https://doi.org/10.1016/j.renene.2022.01.037.
Muratoglu, A., and M. I. Yuce. 2017. “Design of a river hydrokinetic turbine using optimization and CFD simulations.” J. Energy Eng. 143 (4): 04017009. https://doi.org/10.1061/(ASCE)EY.1943-7897.0000438.
Patel, R., and V. Patel. 2022a. “Performance analysis of Savonius hydrokinetic turbine using ‘C’ shaped deflector.” Energy Sources Part A 44 (3): 6618–6631. https://doi.org/10.1080/15567036.2022.2101718.
Patel, V., G. Bhat, T. I. Eldho, and S. V. Prabhu. 2017. “Influence of overlap ratio and aspect ratio on the performance of Savonius hydrokinetic turbine.” Int. J. Energy Res. 41 (6): 829–844. https://doi.org/10.1002/er.3670.
Patel, V., T. I. Eldho, and S. V. Prabhu. 2018. “Theoretical study on the prediction of the hydrodynamic performance of a Savonius turbine based on stagnation pressure and impulse momentum principle.” Energy Convers. Manage. 168 (Jul): 545–563. https://doi.org/10.1016/j.enconman.2018.04.065.
Patel, V., and R. Patel. 2021. “Free energy-extraction using Savonius hydrokinetic rotor with dual splitters.” Mater. Today Proc. 45 (Jan): 5354–5361. https://doi.org/10.1016/j.matpr.2021.01.928.
Patel, V. K., and R. S. Patel. 2022b. “Optimization of an angle between the deflector plates and its orientation to enhance the energy efficiency of Savonius hydrokinetic turbine for dual rotor configuration.” Int. J. Green Energy 19 (5): 476–489. https://doi.org/10.1080/15435075.2021.1947821.
Salleh, M. B., N. M. Kamaruddin, and Z. Mohamed-Kassim. 2022. “Experimental investigation on the effects of deflector angles on the power performance of a Savonius turbine for hydrokinetic applications in small rivers.” Energy 247 (May): 123432. https://doi.org/10.1016/j.energy.2022.123432.
Sarma, N. K., A. Biswas, and R. D. Misra. 2014. “Experimental and computational evaluation of Savonius hydrokinetic turbine for low velocity condition with comparison to Savonius wind turbine at the same input power.” Energy Convers. Manage. 83 (Jul): 88–98. https://doi.org/10.1016/j.enconman.2014.03.070.
Talukdar, P. K., A. Sardar, V. Kulkarni, and U. K. Saha. 2018. “Parametric analysis of model Savonius hydrokinetic turbines through experimental and computational investigations.” Energy Convers. Manage. 158 (Feb): 36–49. https://doi.org/10.1016/j.enconman.2017.12.011.
Thiyagaraj, J., I. Rahamathullah, G. Anbuchezhiyan, R. Barathiraja, and A. Ponshanmugakumar. 2021. “Influence of blade numbers, overlap ratio and modified blades on performance characteristics of the Savonius hydro-kinetic turbine.” Mater. Today Proc. 46 (Jan): 4047–4053. https://doi.org/10.1016/j.matpr.2021.02.568.
Tian, W., Z. Mao, B. Zhang, and Y. Li. 2018. “Shape optimization of a Savonius wind rotor with different convex and concave sides.” Renewable Energy 117 (Mar): 287–299. https://doi.org/10.1016/j.renene.2017.10.067.
Information & Authors
Information
Published In
Copyright
© 2023 American Society of Civil Engineers.
History
Received: Feb 22, 2023
Accepted: Jun 30, 2023
Published online: Aug 28, 2023
Published in print: Dec 1, 2023
Discussion open until: Jan 28, 2024
ASCE Technical Topics:
- Analysis (by type)
- Continuum mechanics
- Dynamics (solid mechanics)
- Engineering fundamentals
- Engineering mechanics
- Engines
- Equations (by type)
- Equipment and machinery
- Material mechanics
- Material properties
- Materials engineering
- Mathematics
- Models (by type)
- Navier-Stokes equations
- Numerical analysis
- Numerical models
- Shear stress
- Solid mechanics
- Stress (by type)
- Structural analysis
- Structural engineering
- Thickness
- Transient response
- Turbines
- Vanes
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.