Dynamic Analysis of the Optimized Savonius Vertical Axis Wind Turbine Composite Blades

2021 ◽  
pp. 1-7
Author(s):  
Sobhy Ghoneam ◽  
Ahmed Hamada ◽  
Taha S. Sherif
Keyword(s):  
Wind Speed ◽  
Wind Turbine ◽  
Dynamic Characteristics ◽  
Dynamic Performance ◽  
Vertical Axis ◽  
Mode Shapes ◽  
Speed Ratio ◽  
Damping Factor ◽  
Vertical Axis Wind Turbine ◽  
Composite Blades

Abstract This paper presents a comprehensive study of the dynamic behavior of small vertical axis wind turbines (VAWTs) based on local fabricated Savonius VAWTs, which is suitable for countries that have moderate wind speed. The merits of this design are cleanliness, silent, start-up under low wind speed, independent wind directions, adaptability and ease of manufacturing. Also, this paper presents an experimental validation study for the optimized Savonius VAWT. Four verification test configurations of the optimized VAWT composite blades are designed, simulated and fabricated of Glass – Polyester with different stacking sequence layout for each. Modified mechanical parameters are introduced to improve the scalability, reliability, and accuracy of the developed models. Based on wind energy conversion system basics, aerodynamic characteristics (tip speed ratio (λ) and coefficient of power (Cp)), dynamic characteristics (natural frequencies and mode shapes) of Savonius-rotor models are presented and simulated within SOLIDWORKS Simulation 2020 software. The dynamic characteristics such as frequency, mode shape and damping factor are extensively investigated using Fast Fourier Transformer (FFT) analyzer. The results show that the role of composite material blades in improving the dynamic performance of a wind turbine is significant.

Design and performance evaluation of vertical axis wind turbine for wind energy harvesting at railway

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Hashwini Lalchand Thadani ◽  
Fadia Dyni Zaaba ◽  
Muhammad Raimi Mohammad Shahrizal ◽  
Arjun Singh Jaj A. Jaspal Singh Jaj ◽  
Yun Ii Go
Keyword(s):  
Wind Speed ◽  
Energy Harvesting ◽  
Wind Energy ◽  
Wind Turbine ◽  
High Speed ◽  
Vertical Axis ◽  
Speed Ratio ◽  
Vertical Axis Wind Turbine ◽  
Modeling Tools ◽  
Content Type

PurposeThis paper aims to design an optimum vertical axis wind turbine (VAWT) and assess its techno-economic performance for wind energy harvesting at high-speed railway in Malaysia.Design/methodology/approachThis project adopted AutoCAD and ANSYS modeling tools to design and optimize the blade of the turbine. The site selected has a railway of 30 km with six stops. The vertical turbines are placed 1 m apart from each other considering the optimum tip speed ratio. The power produced and net present value had been analyzed to evaluate its techno-economic viability.FindingsComputational fluid dynamics (CFD) analysis of National Advisory Committee for Aeronautics (NACA) 0020 blade has been carried out. For a turbine with wind speed of 50 m/s and swept area of 8 m2, the power generated is 245 kW. For eight trains that operate for 19 h/day with an interval of 30 min in nonpeak hours and 15 min in peak hours, total energy generated is 66 MWh/day. The average cost saved by the train stations is RM 16.7 mil/year with battery charging capacity of 12 h/day.Originality/valueWind energy harvesting is not commonly used in Malaysia due to its low wind speed ranging from 1.5 to 4.5 m/s. Conventional wind turbine requires a minimum cut-in wind speed of 11 m/s to overcome the inertia and starts generating power. Hence, this paper proposes an optimum design of VAWT to harvest an unconventional untapped wind sources from railway. The research finding complements the alternate energy harvesting technologies which can serve as reference for countries which experienced similar geographic constraints.

Experimental Study of Vertical Axis Wind Turbine with Wind Speed Self-Adapting

2012 ◽  
Vol 215-216 ◽  
pp. 1323-1326
Author(s):  
Ming Wei Xu ◽  
Jian Jun Qu ◽  
Han Zhang
Keyword(s):  
Wind Speed ◽  
Wind Turbine ◽  
Wind Velocity ◽  
Vertical Axis ◽  
Maximum Power ◽  
The Self ◽  
Power Coefficient ◽  
Speed Ratio ◽  
Vertical Axis Wind Turbine ◽  
Opening And Closing

A small vertical axis wind turbine with wind speed self-adapting was designed. The diameter and height of the turbine were both 0.7m. It featured that the blades were composed of movable and fixed blades, and the opening and closing of the movable blades realized the wind speed self-adapting. Aerodynamic performance of this new kind turbine was tested in a simple wind tunnel. Then the self-starting and power coefficient of the turbine were studied. The turbine with load could reliably self-start and operate stably even when the wind velocity was only 3.6 m/s. When the wind velocity was 8 m/s and the load torque was 0.1Nm, the movable blades no longer opened and the wind turbine realized the conversion from drag mode to lift mode. With the increase of wind speed, the maximum power coefficient of the turbine also improves gradually. Under 8 m/s wind speed, the maximum power coefficient of the turbine reaches to 12.26%. The experimental results showed that the new turbine not only improved the self-starting ability of the lift-style turbine, but also had a higher power coefficient in low tip speed ratio.

Numerical Investigation on Vertical Axis Wind Turbine in Search for an Efficient Design

2015 ◽  
Author(s):  
Mosfequr Rahman ◽  
Mohammad Bashar ◽  
Gustavo Molina ◽  
Valentin Soloiu ◽  
Travis Salyers
Keyword(s):  
Wind Speed ◽  
Wind Turbine ◽  
Lift Coefficient ◽  
Vertical Axis ◽  
Speed Ratio ◽  
Technological Advancement ◽  
Vertical Axis Wind Turbine ◽  
Horizontal Axis Wind Turbine ◽  
The World ◽  
Alternative Sources

The continuous improvement of this world is based on technological advancement. And the technological advancement is directly related to the utilization of energy. The demand of energy is creeping up every day due to increase of population, industrial and agricultural advancement. But the conventional energy sources are becoming limited which is ultimately making them more expensive. In addition to this, everyone is concerned about global climate change. This whole scenario is pushing the world to find the alternative sources of energy. Alternative sources involve natural phenomena such as sunlight, wind, tides, plant growth, and geothermal heat. Solar and Wind power are the most popular among the various sources of renewable energy. Wind alone can fulfill most of the energy requirement of the world by its efficient conversion in to energy. Though Horizontal Axis Wind Turbine (HAWT) is more popular but needs high wind speed to extract energy from the wind. On the Other hand Vertical Axis Wind Turbine (VAWT) can run at low wind speed, independent of wind direction and can be installed anywhere with cheapest cost. The main objective of this research is to improve the design and performance of VAWT to make it more attractive, efficient, durable and sustainable. For a VAWT, the blades perform the main role to extract energy from the wind. Airfoil is considered as the blade for this new design of VAWT. Airfoil has some good aerodynamic characteristics, matches with the characteristics of Savonious type VAWT, such as good stall characteristics and little roughness affect, relatively high drag and low lift coefficient. Three dimensional CAD models of various simple airfoils have been designed in Solidworks. Using these airfoils CFD simulation has been performed for five different VAWT designed models. Moving mesh and fluid flow simulation have been performed using CFD software FLUENT. The findings of these numerical simulations provided pressure contour, velocity contour, drag coefficient, lift coefficient, torque coefficient and power coefficient for all these models. From the results it can be concluded that NACA7510 airfoil VAWT model gives the better performance at higher Tip Speed Ratio (λ) than other models.

scholarly journals Performance of a Small-sized Savonious Blade with Wind Concentrator

2018 ◽  
Vol 10 (3) ◽  
pp. 1227
Author(s):  
Dygku. Asmanissa Awg. Osman ◽  
Norzanah Rosmin ◽  
Aede Hatib Mustaamal ◽  
Siti Maherah Hussin ◽  
Md Pauzi Abdullah
Keyword(s):  
Wind Speed ◽  
Wind Turbine ◽  
Experimental Testing ◽  
Electrical Power ◽  
Vertical Axis ◽  
Angular Speed ◽  
Speed Ratio ◽  
Vertical Axis Wind Turbine ◽  
Air Compressor ◽  
Tip Speed Ratio

<span>This paper presents the performance of a fabricated small-sized Savonious wind turbine with two blades. The design of Savonius vertical axis wind turbine (VAWT) was based on Malaysia wind speed condition. Meanwhile, the design of wind concentrator was based on the dimensions and the constant airflow of an air compressor. From the experimental testing in a laboratory, it was found that the proposed Savonious turbine has best performance when tested using wind concentrator. To conclude, airflow from air compressor can be increased when the proposed wind concentrator is used and hence increasing the proposed VAWT performance in terms of its angular speed (ω), tip speed ratio (TSR) and the generated electrical power (PE).</span>

scholarly journals Experimental Study of Wind Booster Addition for Savonius Vertical Wind Turbine of Two Blades Variations Using Low Wind Speed

2019 ◽  
Vol 125 ◽  
pp. 14003
Author(s):  
Eflita Yohana ◽  
MSK. Tony Suryo U ◽  
Binawan Luhung ◽  
Mohamad Julian Reza ◽  
M Badruz Zaman
Keyword(s):  
Wind Speed ◽  
Wind Energy ◽  
Wind Turbine ◽  
Vertical Axis ◽  
Vertical Wind ◽  
Speed Ratio ◽  
Vertical Axis Wind Turbine ◽  
Tip Speed Ratio ◽  
Average Value ◽  
Low Wind Speed

The Wind turbine is a tool used in Wind Energy Conversion System (WECS). The wind turbine produces electricity by converting wind energy into kinetic energy and spinning to produce electricity. Vertical Axis Wind Turbine (VAWT) is designed to produce electricity from winds at low speeds. Vertical wind turbines have 2 types, they are wind turbine Savonius and Darrieus. This research is to know the effect of addition wind booster to Savonius vertical wind turbine with the variation 2 blades and 3 blades. Calculation the power generated by wind turbine using energy analysis method using the concept of the first law of thermodynamics. The result obtained is the highest value of blade power in Savonius wind turbine without wind booster (16.5 ± 1.9) W at wind speed 7 m/s with a tip speed ratio of 1.00 ± 0.01. While wind turbine Savonius with wind booster has the highest power (26.3 ± 1.6) W when the wind speed of 7 m/s with a tip speed ratio of 1.26 ± 0.01. The average value of vertical wind turbine power increases Savonius after wind booster use of 56%.

A Numerical Study on the Effects of Unsteady Wind on Vertical Axis Wind Turbine Performance

2013 ◽  
Author(s):  
Louis Angelo Danao ◽  
Jonathan Edwards ◽  
Okeoghene Eboibi ◽  
Robert Howell
Keyword(s):  
Wind Speed ◽  
Wind Turbine ◽  
Numerical Study ◽  
Angle Of Attack ◽  
Vertical Axis ◽  
Power Coefficient ◽  
Peak Performance ◽  
Speed Ratio ◽  
Vertical Axis Wind Turbine ◽  
Tip Speed Ratio

Numerical simulations using RANS–based CFD have been utilised to carry out investigations on the effects of unsteady wind in the performance of a wind tunnel vertical axis wind turbine. Using a validated CFD model, unsteady wind simulations revealed a fundamental relationship between instantaneous VAWT CP and wind speed. CFD data shows a CP variation in unsteady wind that cuts across the steady CP curve as wind speed fluctuates. A reference case with mean wind speed of 7m/s, wind speed amplitude of ±12%, fluctuating frequency of 0.5Hz and mean tip speed ratio of 4.4 has shown a wind cycle mean power coefficient of 0.33 that equals the steady wind maximum. Increasing wind speed causes the instantaneous tip speed ratio to fall which leads to higher effective angle of attack and deeper stalling on the blades. Stalled flow and rapid changes in angle of attack of the blade induce hysteresis loops in both lift and drag. Decreasing wind speeds limit the perceived angle of attack seen by the blades to near static stall thus reducing the positive effect of dynamic stall on lift generation. Three mean tip speed ratio cases were tested to study the effects of varying conditions of VAWT operation on the overall performance. As the mean tip speed ratio increases, the peak performance also increases.

Design and Performance Analysis of Distributed Equal Angle Spiral Vertical Axis Wind Turbine

2020 ◽  
Vol 14 (1) ◽  
pp. 120-132
Author(s):  
Li Zheng ◽  
Zhang Wenda ◽  
Han Ruihua ◽  
Tian Yongsheng
Keyword(s):  
Wind Speed ◽  
Wind Energy ◽  
Wind Turbine ◽  
Wind Turbines ◽  
Vertical Axis ◽  
Energy Utilization ◽  
Normal Operation ◽  
Utilization Rate ◽  
Speed Ratio ◽  
Vertical Axis Wind Turbine

Background: The wind turbine is divided into a horizontal axis and a vertical axis depending on the relative positions of the rotating shaft and the ground. The advantage of the choke wind turbine is that the starting torque is large and the starting performance is good. The disadvantage is that the rotation resistance is large, the rotation speed is low, the asymmetric flow occurs when the wind wheel rotates, the lateral thrust is generated, and the wind energy utilization rate is lowered. How to improve the wind energy utilization rate of the resistance wind turbine is an important issue to be solved by the wind power technology. Objective: The nautilus isometric spiral wind turbines studied in this paper have been introduced and analyzed in detail, preparing for the further flow analysis and layout of wind turbines, improving the wind energy utilization rate of wind turbines, introducing patents of other structures and output characteristics of its generator set. Methods: Combined with the flow field analysis of ANSYS CFX software, the numerical simulation of the new wind turbine was carried out, and the aerodynamic performance of the new vertical axis wind turbine was analyzed. The mathematical model and control model of the generator were established by the maximum power control method, and the accuracy of the simulation results was verified by the measured data. Results: The basic parameters of the new wind turbine tip speed ratio, torque coefficient and wind energy utilization coefficient are analyzed. Changes in wind speed, pressure and eddy viscosity were investigated. Three-dimensional distribution results of wake parameters such as wind speed and pressure are obtained. By simulating the natural wind speed, the speed and output current of the generator during normal operation are obtained. Conclusion: By analyzing the wind performance and power generation characteristics of the new wind turbine, the feasibility of the new wind turbine is determined, which provides reference and reference for the optimal design and development of the wind turbine structure.

An improved LB method for predicting dynamic characteristics of Vertical Axis Wind Turbine airfoils

2022 ◽  
pp. 0309524X2110671
Author(s):  
Shoutu Li ◽  
Qing Wang ◽  
Congxin Yang
Keyword(s):  
Wind Turbine ◽  
Dynamic Characteristic ◽  
Dynamic Characteristics ◽  
Lift Coefficient ◽  
Vertical Axis ◽  
Accurate Method ◽  
Operating Conditions ◽  
Speed Ratio ◽  
Vertical Axis Wind Turbine ◽  
Tip Speed Ratio

One of the important challenges for Vertical Axis Wind Turbine (VAWT) is to fully understand its dynamic characteristics in different operating conditions. Meanwhile, it is necessary to seek a fast and accurate method to evaluate the dynamic characteristic of VAWT. In this study, we improve the LB model by considering the operating principle of VAWT to study the dynamic characteristics of the dedicated and commonly used VAWT airfoils in different operating conditions. The results show that the improved LB model is suitable for simulating the dynamic characteristic of VAWT with a thick airfoil. Although the asymmetric airfoil shows the higher lift coefficient, their dynamic characteristic appears huge fluctuation as the increases of tip speed ratio. Moreover, at a low tip speed ratio, the advantages of the asymmetric airfoil are not obvious. While the dynamic characteristic of the symmetric airfoil is relatively stable with the variation of tip speed ratio.

Influence of Load Level on Performance of Standalone Vertical Axis Wind Turbine System

2009 ◽  
Vol 33 (3) ◽  
pp. 213-235 ◽  
Author(s):  
Tetsuya Wakui ◽  
Ryohei Yokoyama ◽  
Hiroyuki Arase
Keyword(s):  
Power Generation ◽  
Wind Speed ◽  
Wind Turbine ◽  
Vertical Axis ◽  
Load Level ◽  
Speed Ratio ◽  
Vertical Axis Wind Turbine ◽  
Wind Turbine System ◽  
Low Load ◽  
Mean Wind Speed

The influence of load level on the performance of a stand-alone, straight-wing, vertical axis wind turbine system in terms of its power generation capability and output fluctuation during operation is numerically investigated using a dynamic simulation model. The system is mainly operated at a constant tip-speed ratio, i.e., at a maximum power coefficient point, by load control in proportion to the square of rotational speed. Thus, the steady-state performance and dynamic behavior of the system under four load levels are analyzed. Then, the dynamic system performance under different load levels is discussed. This work shows that, under high mean wind speed conditions, a low load level is undesirable because it would cause an increase in the output fluctuation. However, under low mean wind speed conditions, a low load level could be effective in improving the power generation capability, with only a slight increase in the output fluctuation.

A Suitable Load Control Method for Constant Tip Speed Ratio Operation of Stand-Alone Wind Turbine-Generator Systems

2008 ◽  
Vol 32 (2) ◽  
pp. 143-161 ◽  
Author(s):  
Tetsuya Wakui ◽  
Ryohei Yokoyama
Keyword(s):  
Measurement Error ◽  
Wind Speed ◽  
Wind Turbine ◽  
Rotational Speed ◽  
Control Method ◽  
Vertical Axis ◽  
Load Control ◽  
Speed Ratio ◽  
Vertical Axis Wind Turbine ◽  
Tip Speed Ratio

A suitable load control method for constant tip speed ratio operation of a stand-alone system using a vertical axis wind turbine with self-starting capability is discussed. The system with a straight-wing-type turbine is mainly operated at a constant tip speed ratio. Two types of load control methods are considered: Method-1, where the load torque is controlled in proportion to the square of the rotational speed, and Method-2, which adopts feedback control of the rotational speed in response to the measured wind speed. In this second report on a suitable load control method, the influence of the measurement error of the inflow wind speed is particularly focused on. The computational results obtained using the dynamic simulation model show that Method-1, which is not affected by the measurement error and has a fine smoothing effect of the output fluctuation, is the more suitable load control method.

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