Numerical analysis of the one-stage and two-stage helical Savonius vertical axis wind turbine (original) (raw)
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Simulation Study on the Performance of Vertical Axis Wind Turbine
Applied Mechanics and Materials, 2013
The present study considered the design improvement of Savonius rotor, in order to increase the efficiency of output power. An investigation was conducted to study the effect of geometrical configuration on the performance of the rotor in terms of coefficient of torque, coefficient of power and power output. Modification of conventional geometry has been designed by combining the effect of number of blades and shielding method. CFD simulation was conducted to analyze the flow characteristic and calculate the torque coefficient of all the rotor configurations. The continuity and Reynolds Averaged Navier-Stokes (RANS) equations and realizable k-ε epsilon turbulence model are numerically solved by commercial software Ansys-Fluent 14.0. The results obtained by transient and steady method for the conventional two bladed Savonius rotor are in agreement with those obtained experimentally by other authors and this indicates that the methods can be successfully applied for such analysis. The...
E3S Web of Conferences, 2021
In this study, the researcher applied an experimental method to examine the performance of theSavonius-type turbine, in which variations in the blade angle were 85°, 95°, 105°, 110°, 115°, and 125°, variations in wind speed were 3 and 4.1 m/s, and variations in balancing force were 0.4 and 0.9 kg. The results showed that, of the five examined variations of the blade angle, the 125° blade produced the highest rotation (n) compared to the others. It generated 115.3 rpm but without a balanced force. Furthermore, the turbine performance at a wind speed (V) of 4.1 m/s, a balancing force (F) of 0.9 kg, and a blade angle of 125° produced the rotational speed (n) of 69.6 rpm, the turbine power (Pt) of 6.43 watts, the torque (T) of 1.765 N.m, the tip-speed ratio (λ) of 0.355, and the turbine efficiency 66.22%. Meanwhile, at a wind speed of 3 m/s, a balancing force (F) of 0.9 kg, and a blade angle of 125°, it generated the rotational speed (n) of 28.6 rpm, the turbine power (Pt) of 2.64 watts...
Design, simulation and performance evaluation of vertical axis helical wind turbine
2019
This report is all about the design, simulation, fabrication, and performance evaluation of the VAHWT. The experimental data obtained via testing and data from CFD approach are used for performance evaluation. From the data obtained experimentally, the VAHWT so fabricated has been found to operate at the low cutin speed of 3.18 m/s and maximum power output has been found to be 2.656 watts at the wind speed of 8 m/s. The maximum rpm of the rotor blade is recorded to be 722.2 rpm at the velocity of 11.53 m/s signifying its potentiality of wind power production. Besides, the data so obtained from both the process when analyzed through graph plots, has shown the similar nature slope wise. This simply signifies the generation of satisfactory data via experiment. In addition, the mechanical losses has shown difference between the experimental and data obtained via CFD approach. At the end, when applying CFD approach for evaluation of maximum efficient turbine varying the aspect ratio, has shown the turbine with aspect ratio of 0.6531 to be the most efficient with performance coefficient of 36.396%. However due to limitation in RPM and Test rig, the rotor blade with aspect ratio of 0.6956 was fabricated and used for evaluation experimentally. The data so obtained from both the process were concluded to be relevant to each other. Thus, the detail study on this project has led to the need and opportunity of VAHWT to be further researched and can be developed as a good source of energy producing system. It can also be economical method of power extraction from wind in the countries like Nepal with growing urbanization.
Energies
Small-scale vertical-axis wind power generation technologies such as Savonius wind turbines are gaining popularity in suburban and urban settings. Although vertical-axis wind turbines (VAWTs) may not be as efficient as their horizontal-axis counterparts, they often present better opportunities for integration within building structures. The main issue stems from the suboptimal aerodynamic design of Savonius turbine blades, resulting in lower efficiency and power output. To address this, modern turbine designs focus on optimizing various geometric aspects of the turbine to improve aerodynamic performance, efficiency, and overall effectiveness. This study developed a unique optimization method, incorporating a new blade geometry with guide gap flow for Savonius wind turbine blade design. The aerodynamic characteristics of the Savonius wind turbine blade were extensively analyzed using 3D ANSYS CFX software. The optimization process emphasized the power coefficient as the objective fun...
CFD Letters
Small-scale wind turbines are considered recently as an attractive source of renewable energy, especially at remote area with respect to city centre. The design and characterization of a small vertical wind turbine are introduced through this work. A CFD analysis has been used as a first step in design to simulate the flow around the vertical blades of the small wind turbine. Different parameters have been taken into account in this work such as blades number, shape, and existence of stator blades deflector. Three different versions depend on blade profile have been examined. The turbulence model with sliding mesh in CFD have been performed. In this paper, a performance of small-scale of vertical wind turbine represented by CFD results of power coefficient, and optimal freestream velocity of this model are presented. The results showed that using 8 blades of VAWT instead of 4 blades with the same profile of blade has enhanced VAWT performance up to 64%. Also, increasing the concave ...
2019
Vertical axis wind turbines (VAWT) are omnidirectional in nature. Lift type work on the conditions of lift produced on blades. Drag type harness power from wind by the effect of drag force. VAWTs require no yaw mechanism to continuously orient towards the wind direction. This work deals with the review study of vertical axis lift and drag type rotors and identifying various performance parameters to increase the power performance. It is observed that helical rotor has self starting capacity at low wind speeds. The egg beater shape has better stress bearing capacity as compared to other shapes, but generated insufficient torque for self starting nature. Number of blades for optimal performance for tip speed ratios between three to five were adequate when taken as three. Whereas for tip speed ratios less than three, four blades are optimal. For drag type rotors, it has been concluded that helical blades are more inclined towards self starting nature than conventional bucket type shape...
DESIGN & DEVELOPMENT OF VERTICAL AXIS WIND TURBINE
Increasing demand for energy in recent years has seen a rise in development of alternative energy sources. Wind being one of the most abundant and easily available sources is an excellent alternative to conventional energy sources.
Design and Analysis of Savonius Vertical Axis Wind Turbine
In recent era, research and development activities in the field of renewable energy, especially wind and solar, have been considerably increased, due to the worldwide energy crisis and high global emission. The horizontal axis wind turbine cannot be used for household purpose. So, Savonius vertical axis wind turbine can be better option as it operate in low wind condition also. The choice for this model is to showcase its efficiency in varying wind conditions as compared to the traditional horizontal axis wind turbine and contribute to its steady growing popularity for the purpose of mass utilization in the near future as a reliable source of power generation..
IRJET, 2021
We all know the harm that CO2 emissions of thermal power plant has done to life on earth; so we have to search for a more sustainable alternative like wind energy for energy production. Study of India's wind potential was carried out by the prof. Jami Hoossain of TERI Delhi and proposed that India has more than 200GW capacity. The best way to achieve this goal of 200GW is to use VAWT, which can be operated at very low wind speed and not like HAWT. Here we are designing the small actual prototype of VAWT for OFF grid connections. We have tried to achieve the benefit of combining the Savonius and Darrieus VAWT, such that assembly will start at low speed and will produce the high power at high speed and more power than that of standalone Savonius or Darrieus turbines. In this paper we have used S1210 aero foil to design wings and its effect is analyzed with ANSYS FLUENT. We have checked the usefulness of helical shape for both VAWT rotors. In this paper we have performed analysis on rotors assembly with ANSYS FLUENT. Here we have used FDM rapid prototyping technology and studied its usefulness for future applications. In this paper we are listing some materials for wing design.
Investigating a Modified Vertical Axis Wind Turbine
ERJ. Engineering Research Journal
This investigation aims to analyze experimentally and numerically the performance of the Savonius wind turbine with a modified blade shape/profile. The wind turbine rotor introduced consists of two hook-shaped buckets connected by a Batch/arm with different bucket orientations. Blades of the cross-section with different thicknesses are considered. The simulations are carried out using the three-dimensional incompressible unsteady Reynolds-Average Navier Stokes (RANS) equations along with the RNG k-ε turbulence model. The results indicate that the RNG k-ε turbulence model achieves a good prediction of the rotor performance, in comparison with the literature and the current measurements. Six rotor models are investigated to explore the effect of rotor shape along with blade thickness on the wind turbine performance. It is revealed that the rotor model with a blade thickness of 2 mm and bucket orientation with a parallel armbucket, Model 4, has the best performance among the tested rotors. The static torque shows positive values for all rotor angles with a maximum static torque coefficient of 0.45, which reveals the high starting ability of the present rotor.