Savonius wind turbine

About: Savonius wind turbine is a research topic. Over the lifetime, 333 publications have been published within this topic receiving 6521 citations.

Experimental Study to Assess the Performance of Combined Savonius Darrieus Vertical Axis Wind Turbine at Different Arrangements

Abstract: Darrieus Vertical axis wind turbines (VAWT) have become one of the most worked on turbines in the 20th century, due to the various improvement regimes been carried out to improve their performance, especially the H-shaped Darrieus wind turbines. The Darrieus wind turbines are considered more aerodynamically efficient than the rest of VAWT, however they have been highly undesirable in areas with low wind velocities since these turbines have poor starting torque and are hence unable to self-start in weaker wind speeds. Combined Savonius Darrieus wind turbines have been pitched as the solution for improving turbine's torque characteristics and enable it to self-start. In this study, an experimentation has been carried out to test three possible arrangements of Darrieus and Savonius wind turbine; termed as arrangement 1, 2 & 3, under similar operating conditions to assess performance of each arrangement. It was observed from the arrangement 1; where Savonius rotor was attached at the middle of Darrieus wind turbine, had the highest coefficient of performance among all arrangements, achieving maximum COP of 20% at TSR of 0.86. Arrangement 2 and 3; Savonius rotor attached at the top of Darrieus rotor and Savonius attached at the bottom of Darrieus turbine had significantly lower COP than arrangement 1 - having COP of 10% at 0.56 TSR and 5% at 0.28 TSR, respectively. Henceforth, arrangement 1 is recommended if turbines are to be combined.

CFD Investigation of A New Elliptical-Bladed Multistage Savonius Rotors

Abstract: The Savonius -conventional wind turbine is a class of wind turbines designed with a vertical axis. It has a good starting capacity and an insensitivity to wind direction. It works relatively at low wind speed in an easy installation. Savonius wind turbine faces major drawbacks, including some of the low efficiency and high negative torque created by the returning blade. Many attempts have been undertaken to optimize the blade’s shape to increase the performance of these wind turbines. The vertical axis is still under development. The elliptical-blades with a cut angle equal 47.50° have recently shown enhanced performance. In this study, we investigate the effect of Elliptical-bladed multistage Savonius Rotors (rotor aspect ratio, stage aspect ratio) on the performance by means of numerical simulation. The results obtained by comparison of one, two, and three-stage rotors indicate that the maximum power coefficient increase with a number of the stages (for the rotors with similar RAR of 0.7). Moreover, for the rotors with similar SAR of 0.7, the two stages have the highest performance than others.

Numerical study of two and three bladed Savonius wind turbine

Abstract: The aim of this paper is to compare aerodynamic characteristics of two and three bladed Savonius rotor with different overlap ratios by numerical analysis. The models with 0%, 20%, and 30% overlap having the same blade diameter and height are used for the comparison. To ensure the simulation model was correct the results obtained from the CFD were compared with experimental results. The established simulation model was used to find the static torque coefficients and power coefficients to analyze the aerodynamic performance of the taken geometries. From the analysis it was found that rotor with less blade number produces higher torque. It was also found that the rotors with no overlap produces negative torque and the introduction of overlaps in the rotor eliminates the negative torque. Another finding from the analysis is the increase in Reynolds number increases the static torque in the rotor.

Design and Static Structural Analysis of a 2.5 kW Combined Darrieus-Savonius Wind Turbine

Abstract: Modeling and simulation of mechanical structures in development phase are fundamental to optimize and improve the stability and reliability of the final product as well as to reduce the cost of prototyping and testing Wind turbines are subject to critical loading to the centrifugal force due to wind speed and gravitational force The present study discusses three-dimensional numerical simulations of combined Darrieus-Savonius wind turbine D-SWT for applications in urban and isolated areas for lighting, pumping water, etc The Darrieus turbine is used to produce wind power and the Savonius rotor to start the system Finite Element Analysis (FEA) using SolidWorks 2015 is employed to generate the geometry of the structure and SolidWorks Simulation to investigate the stability and reliability static on the structure of the D-WST built by two types of material of the blade Galvanized Steel (GS) and Aluminum alloys 1060-H18 (ALU) Mechanical parameter of the structure are calculated for critical loading conditions, including the gravity and wind pressure loading due to the wind speed of 23m/s Simulations results indicate no structural failure is predicted for all components of the D-SWT for both materials used according to Von Mises criterion stresses and the factors of safety of the most fragile material are greater than (the unity) 1 The maximum displacements found (384 & 681mm), occurred at the tip blades (free ends levels) These displacements are accepted relatively to the structure size