Investigation of multi rotor small horizontal axis wind turbine at low wind speeds

ABSTRACT Generally, the environmental wind speeds in urban areas are relatively low due to clustered buildings. At low wind speeds, an aerodynamic stall occurs near the blade roots of a horizontal axis wind turbine (HAWT), leading to decay of the power coefficient. The research targets to design canards with optimal parameters for a small-scale HAWT system operated at variable rotational speeds. The design was to enhance the performance by delaying the aerodynamic stall near blade roots of the HAWT to be operated at low wind speeds. For the optimal design of canards, flow fields of the sample blades with and without canards were both simulated and compared with the experimental data. With the verification of our simulations, Taguchi analyses were performed to seek the optimum parameters of canards. This study revealed that the peak performance of the optimized canard system operated at 540 rpm might be improved by ∼35%.

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Basic Design and Blade Structural Analysis of a Small Horizontal-Axis Wind Turbine for Low Wind Speeds

ASME 2020 Power Conference ◽

10.1115/power2020-16554 ◽

2020 ◽

Author(s):

A. R. Krishnanunni ◽

N. Datta ◽

H. S. Chambhare ◽

D. Swaroop

Keyword(s):

Structural Analysis ◽

Wind Turbine ◽

Horizontal Axis ◽

Weather Data ◽

Power Coefficient ◽

Speed Ratio ◽

Basic Design ◽

Horizontal Axis Wind Turbine ◽

Wind Speeds ◽

Low Wind Speeds

Abstract The basic design and blade structural analysis of a 250 W rooftop-mounted horizontal-axis wind turbine for low wind speeds is presented. A simplified non-dimensional design is first undertaken to optimize the aerodynamic performance. The non-dimensional power curve vs. the design tip speed ratio is computed with the open-source wind turbine design software QBlade. SD7062 airfoil is chosen for the blade section; and its aerodynamic efficiency is obtained for various angles of attack using XFLR5. The design process also gives the optimal chord length and pitch distribution, leading to the blade geometry. The 22-month weather data at the site has been analyzed to obtain the best-fit Weibull distribution. The blade sizing is based on the maximum power coefficient before the stall regulation happens. An attempt is made to enhance the power capture by using a concentrator, whose aerodynamic efficacy is analyzed. The blades are fabricated from Glass Fiber Reinforced Plastic, which reduces both weight and cost. The configuration for the laminate is finalized after several bending and tensile tests of five distinct GFRP samples. This is followed by the structural analysis of the blade. The root stresses and tip deflection are analyzed for extreme-wind conditions, along with the free vibration frequencies.

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Optimal Design of Horizontal Axis Wind Turbine Blades

Volume 3: Design; Tribology; Education ◽

10.1115/esda2008-59204 ◽

2008 ◽

Cited By ~ 1

Author(s):

Ohad Gur ◽

Aviv Rosen

Keyword(s):

Wind Speed ◽

Wind Turbine ◽

Design Method ◽

Turbine Blades ◽

Horizontal Axis ◽

Optimization Strategy ◽

Wind Turbine Blades ◽

Horizontal Axis Wind Turbine ◽

Wind Speeds ◽

Design Variables

The optimal aerodynamic design of Horizontal Axis Wind Turbine (HAWT) is investigated. The Blade-element/Momentum model is used for the aerodynamic analysis. In the first part of the paper a simple design method is derived, where the turbine blade is optimized for operation at a specific wind speed. Results of this simple optimization are presented and discussed. Besides being optimized for operation at a specific wind speed, without considering operation at other wind speeds, the simple model is also limited in the choice of design goals (cost functions), design variables and constraints. In the second part of the paper a comprehensive design method that is based on a mixed numerical optimization strategy, is presented. This method can handle almost any combination of: design goal, design variables, and constraints. Results of this method are presented, compared with the results of the simple optimization, and discussed.

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Parametric study of a horizontal axis wind turbine with similar characteristics to those of the Villonaco wind power plant

Journal of Applied Research in Technology & Engineering ◽

10.4995/jarte.2021.15056 ◽

2021 ◽

Vol 2 (2) ◽

pp. 51

Author(s):

Santiago Sánchez ◽

Victor Hidalgo ◽

Martin Velasco ◽

Diana Puga ◽

P. Amparo López-Jiménez ◽

...

Keyword(s):

Wind Speed ◽

Wind Turbine ◽

Energy Production ◽

Electrical Energy ◽

Horizontal Axis ◽

Horizontal Axis Wind Turbine ◽

Wind Speeds ◽

Electrical Energy Production ◽

Python Programming ◽

Selection Of

<p class="JAREAbstract">The present paper focuses on the selection of parameters that maximize electrical energy production of a horizontal axis wind turbine using Python programming language. The study takes as reference turbines of Villonaco wind field in Ecuador. For this aim, the Blade Element Momentum (BEM) theory was implemented, to define rotor geometry and power curve. Furthermore, wind speeds were analyzed using the Weibull probability distribution and the most probable speed was 10.50 m/s. The results were compared with mean annual energy production of a Villonaco’s wind turbine to validate the model. Turbine height, rated wind speed and rotor radius were the selected parameters to determine the influence in generated energy. Individual increment in rotor radius and rated wind speed cause a significant increase in energy produced. While the increment in turbine’s height reduces energy generated by 0.88%.</p>

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Modeling and Performance Analysis of a Small Horizontal Axis Wind Turbine

Journal of Energy Resources Technology ◽

10.1115/1.4047972 ◽

2020 ◽

Vol 143 (3) ◽

Author(s):

Osarobo Ighodaro ◽

David Akhihiero

Keyword(s):

Wind Turbine ◽

Fossil Fuels ◽

Renewable Energy Sources ◽

Horizontal Axis ◽

Power Coefficient ◽

Computational Technique ◽

Horizontal Axis Wind Turbine ◽

Design And Optimization ◽

Wind Speeds ◽

Improved Design

Abstract Wind energy is increasingly becoming a major discussion amongst renewable energy sources due to its sustainability, reduced impact on the environment, and being significantly cheaper than conventional fossil fuels. Researchers have been particularly concerned with studying improved design and optimization using computational technique and experimentation. This research aims at designing blades for a small horizontal axis wind turbine for low Reynolds number using blade element momentum theory and using computational fluid dynamics (cfd) and experiment to analyze its performance. Two airfoils (SG6050 and SG6043) were selected for different regions of the blade span. Four turbulent models were used in predicting its performance. The performance was analyzed for wind speeds between 2 m/s and 7 m/s. Studies showed that the blade is capable of generating power up to 241 W with a power coefficient of 34.3% at a speed of 6 m/s. The computed power coefficient is in good agreement with experimental results of 33.7%.

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Computational Analysis of an Optimized Curved-Bladed Small-Scale Horizontal Axis Wind Turbine

Journal of Energy Resources Technology ◽

10.1115/1.4048531 ◽

2020 ◽

Vol 143 (6) ◽

Author(s):

Ali M. Abdelsalam ◽

W. A. El-Askary ◽

M. A. Kotb ◽

I. M. Sakr

Keyword(s):

Wind Turbine ◽

Flow Behavior ◽

Horizontal Axis ◽

Power Coefficient ◽

Peak Performance ◽

Small Scale ◽

Horizontal Axis Wind Turbine ◽

Axial Thrust ◽

Wind Speeds ◽

Linear Profiles

Abstract This article aims to study numerically the effect of curvature of linear blade profile on the performance of small-scale horizontal axis wind turbine (SSHAWT). Rotors with two curvature types, f forward angles 5 deg, 10 deg, 15 deg, 20 deg, 30 deg, and 45 deg and backward angles −5 deg, −10 deg, and −15 deg, are investigated. Furthermore, three curvature positions of r/R = 0.8, 0.9, and 0.95 are studied. The numerical simulations are performed on rotors of radius 0.5 m at different wind speeds. The results are compared with straight rotor of linear profiles of chord and twist, which is considered as base rotor. It is found that the rotor with forward curvature of 5 deg and r/R = 0.9 has the highest power coefficient compared with the other rotors. At the peak performance, the proposed rotor reduces the axial thrust by about 12.5% compared with the base rotor. The flow behavior represented by the streamlines contours is also discussed. In such case, the separation approximately disappeared for the tip speed ratios of 5 and 6, which is responsible for the performance peak.

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Aerodynamic Investigation of a Horizontal Axis Wind Turbine with Split Winglet Using Computational Fluid Dynamics

Energies ◽

10.3390/en13184983 ◽

2020 ◽

Vol 13 (18) ◽

pp. 4983 ◽

Cited By ~ 1

Author(s):

Miguel Sumait Sy ◽

Binoe Eugenio Abuan ◽

Louis Angelo Macapili Danao

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Renewable Energy ◽

Wind Turbine ◽

Renewable Energy Sources ◽

Horizontal Axis ◽

Horizontal Axis Wind Turbine ◽

Wind Speeds ◽

Blade Tip ◽

Nrel Phase Vi

Wind energy is one of the fastest growing renewable energy sources, and the most developed energy extraction device that harnesses this energy is the Horizontal Axis Wind Turbine (HAWT). Increasing the efficiency of HAWTs is one important topic in current research with multiple aspects to look at such as blade design and rotor array optimization. This study looked at the effect of wingtip devices, a split winglet, in particular, to reduce the drag induced by the wind vortices at the blade tip, hence increasing performance. Split winglet implementation was done using computational fluid dynamics (CFD) on the National Renewable Energy Lab (NREL) Phase VI sequence H. In total, there are four (4) blade configurations that are simulated, the base NREL Phase VI sequence H blade, an extended version of the previous blade to equalize length of the blades, the base blade with a winglet and the base blade with split winglet. Results at wind speeds of 7 m/s to 15 m/s show that adding a winglet increased the power generation, on an average, by 1.23%, whereas adding a split winglet increased it by 2.53% in comparison to the extended blade. The study also shows that the increase is achieved by reducing the drag at the blade tip and because of the fact that the winglet and split winglet generating lift themselves. This, however, comes at a cost, i.e., an increase in thrust of 0.83% and 2.05% for the blades with winglet and split winglet, respectively, in comparison to the extended blade.

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Observation of the Starting and Low Speed Behavior of Small Horizontal Axis Wind Turbine

Journal of Wind Energy ◽

10.1155/2014/527198 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Sikandar Khan ◽

Kamran Shah ◽

Izhar-Ul-Haq ◽

Hamid Khan ◽

Sajid Ali ◽

...

Keyword(s):

Wind Turbine ◽

Wind Turbines ◽

Horizontal Axis ◽

Horizontal Axis Wind Turbine ◽

Wind Speeds ◽

Starting Time ◽

Speed Range ◽

Horizontal Axis Wind Turbines ◽

Starting Torque ◽

High Angles Of Attack

This paper describes the starting behavior of small horizontal axis wind turbines at high angles of attack and low Reynolds number. The unfavorable relative wind direction during the starting time leads to low starting torque and more idling time. Wind turbine models of sizes less than 5 meters were simulated at wind speed range of 2 m/s to 5 m/s. Wind turbines were modeled in Pro/E and based on the optimized designs given by MATLAB codes. Wind turbine models were simulated in ADAMS for improving the starting behavior. The models with high starting torques and less idling times were selected. The starting behavior was successfully improved and the optimized wind turbine models were able to produce more starting torque even at wind speeds less than 5 m/s.

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Combining Computational Fluid Dynamics and Gradient Boosting Regressor for Predicting Force Distribution on Horizontal Axis Wind Turbine

Vibration ◽

10.3390/vibration4010017 ◽

2021 ◽

Vol 4 (1) ◽

pp. 248-262

Author(s):

Nikhil Bagalkot ◽

Arvind Keprate ◽

Rune Orderløkken

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Wind Turbine ◽

Structural Integrity ◽

Horizontal Axis ◽

Gradient Boosting ◽

Force Distribution ◽

Horizontal Axis Wind Turbine ◽

Suitable Alternative ◽

Wind Speeds

The blades of the horizontal axis wind turbine (HAWT) are generally subjected to significant forces resulting from the flow field around the blade. These forces are the main contributor of the flow-induced vibrations that pose structural integrity challenges to the blade. The study focuses on the application of the gradient boosting regressor (GBR) for predicting the wind turbine response to a combination of wind speed, angle of attack, and turbulence intensity when the air flows over the rotor blade. In the first step, computational fluid dynamics (CFD) simulations were carried out on a horizontal axis wind turbine to estimate the force distribution on the blade at various wind speeds and the blade’s attack angle. After that, data obtained for two different angles of attack (4° and 8°) from CFD acts as an input dataset for the GBR algorithm, which is trained and tested to obtain the force distribution. An estimated variance score of 0.933 and 0.917 is achieved for 4° and 8°, respectively, thus showing a good agreement with the force distribution obtained from CFD. High prediction accuracy and less time consumption make GBR a suitable alternative for CFD to predict force at various wind velocities for which CFD analysis has not been performed.

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Designing a Tapperless Blade with an S-4320 Airfoil on a Micro-Scale Horizontal Axis Wind Turbine (Case Studies at PT Lentera Bumi Nusantara)

MOTIVECTION : Journal of Mechanical, Electrical and Industrial Engineering ◽

10.46574/motivection.v3i1.81 ◽

2021 ◽

Vol 3 (1) ◽

pp. 27-34

Author(s):

Reza Simatupang ◽

Deddy Supriatna

Keyword(s):

Wind Turbine ◽

Quantitative Research ◽

Horizontal Axis ◽

Blade Design ◽

Horizontal Axis Wind Turbine ◽

Microsoft Excel ◽

Quantitative Research Methods ◽

Micro Scale ◽

Wind Speeds ◽

Horizontal Axis Wind Turbines

This article aims to design a taperless blade in a micro-scale wind turbine in medium wind speed, a case study at PT Lentera Bumi Nusantara. The methodology used in this research is quantitative research methods. Based on the test results in calculating the data using Microsoft Excel software and the blade airfoil design simulation using Qblade software, the use of the S-4320 airfoil in the application of the taperless blade design has research results that show that the airfoil design of the blade produces mechanical power at moderate wind speeds. It can be concluded that this blade design shows that the taperless blade with S-4320 airfoil can be applied to medium wind speeds in micro-scale horizontal axis wind turbines. Artikel ini bertujuan untuk merancang bilah jenis taperless pada turbin angin skala mikro dalam kecepatan angin sedang, studi kasus pada PT Lentera Bumi Nusantara. Metodologi yang digunakan dalam penelitian ini adalah dengan metode penelitian kuantitatif. Berdasarkan hasil pengujian dalam perhitungan data menggunakan software Microsoft Excel dan simulasi perancangan desain airfoil bilah menggunakan software Qblade, penggunaan airfoil S-4320 dalam pengaplikasian desain bilah jenis taperless memiliki hasil penelitian yang menunjukan bahwa desain airfoil bilah tersebut menghasilkan tenaga mekanik pada kecepatan angin sedang. Dapat disimpulkan dalam desain bilah ini menunjukan bahwa bilah jenis taperless dengan airfoil S-4320 dapat diterapkan pada kecepatan angin sedang pada turbin angin sumbu horizontal skala mikro.

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