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.
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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.
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Information & Authors
Information
Published In
Journal of Energy Engineering
Volume 149 • Issue 6 • December 2023
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
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