Performance Of Horizontal Axis Wind Turbine Research Articles

Impact Tip Speed Ratio in Performance Analysis for Horizontal Axis Wind Turbine (HAWT) with Optimal Twist and Tapered (OPT) Blade Shape

Performance for Horizontal Axial Wind Turbine (HAWT) is influenced by the difference in tip speed ratio (TSR) and mesh distribution. The objective of this article is to study the optimal performance of wind turbines when subjected to different mesh resolution, TSR and wind speed velocity.Therefore, it is important to study the effects of different mesh resolutions in terms of wind turbine performance. To achieve that, a 0.65m optimal twist and tapered (OPT) blade is used with various inlet velocities and TSR. This study uses the k-ꞷ shear-stress transport (SST) based Reynold-Average Navier Stokes (RANS) approach in commercial ANSYS Fluent CFD software. This simulation was performed using the Moving Ratio Frame (MRF) method. To find the optimum grid resolution, a Grid Independence Test (GIT) was conducted comparing the coefficient of power (Cp). From the RESULT, TSR 6 shows the best HAWT performance when Cp for inlet velocity 8 m/s is 0.2608.

Current Trends and Innovations in Enhancing the Aerodynamic Performance of Small-Scale, Horizontal Axis Wind Turbines: A Review

Abstract Wind energy has proven to be one of the most promising resources to meet the challenges of rising clean energy demand and mitigate environmental pollution. The global new installation of wind turbines in 2022 was 77.6 GW, bringing the total installed capacity to 906 GW, documenting an astounding 9% growth in just one year (Lee and Zhao, 2023, Global Wind Report, GWEC. Global Wind Energy Council). Sizeable research continues to focus on improving wind energy conversion, safety, and capacity. However, funding allocations and research have not matched this sustained market growth observed over the last few decades. This is particularly the case for small-size wind turbines. We define small-scale wind turbines as those with an output power of 40 kW or less that can nonetheless be interconnected to provide larger power output. Thus, the paper focuses on small-scale horizontal-axis wind turbines (HAWT) with emphasis on current technology trends including data gathering, aerodynamic performance analysis of airfoils and rotors, as well as computational approaches. The paper also highlights the challenges associated with small-scale HAWTs thereby conjecturing about future research directions on the subject. The literature review suggests that small-scale HAWT wind turbines are suitable for harnessing energy in communities with limited resources where grid-supplied power is out of reach. The power coefficient of these turbines ranges from 0.2 to 0.45 which shows that it could greatly benefit from research, built on targeting these modest performance scales by using efficient airfoils, mixed airfoils, optimizing the blade geometry, shrouding the wind turbine rotor, using maximum power tracking control, etc. This review paper is an attempt to prioritize and layout strategies toward evaluating and enhancing the aerodynamic performance of small-scale HAWTs.

Assessment of Correction Methods Applied to BEMT for Predicting Performance of Horizontal-Axis Wind Turbines

Blade Element Momentum Theory (BEMT) is the most used method to design horizontal-axis wind turbines worldwide. This is because BEMT has a low computational cost and easy numerical implementation. Additionally, it is demonstrated in the literature that the prediction of output power using BEMT agrees well with experimental data. Another important feature of the BEMT is its applicability to small, medium, and large-sized turbines. However, BEMT models are usually implemented and adjusted for a specific power range turbine, and they are not applied in a more general form. Thus, this article presents an analysis of additional correction methods for tip and root losses, high values of the axial induction factor, and high angle of attack to better represent horizontal-axis turbines in terms of numerical stability. The approach has the intention of combining several complementary correction methods strategically inserted in the BEMT in order to compile an algorithm that is more general, stable, and workable for any turbine size. The main contribution of this work is to propose a stable BEMT numerical algorithm through the assessment of the combination of the correction methods available in the literature, i.e., classical and modern ones. The algorithm ensures applicability for small, medium, and large-sized wind turbines, as well as being fast and easy to implement in any computer and extendable even to turbines with a diffuser. This approach is validated by comparing the results with experimental data from four turbines of different power ranges (1.9 kW to 7.3 MW). The results show the best approximations for performance power curves against the measured values of all turbines. Moreover, it is effective, less complex, and quick in analyzing the performance of those turbines. Furthermore, the need for high-performance computers to analyze the performance of horizontal-axis turbines is avoided.

Optimum design of morphing flaps for improving horizontal axis wind turbine performance

AbstractThis study presents a conceptual design of optimum deformable blades as a function of wind speed. In this design, at any speed of wind flow, the blade sections have their optimal shape. Accordingly, the wind turbine performance will increase at different speeds. The WindPACT 1.5‐MW wind turbine is used as the base turbine, which has three different sections at the root, middle, and tip of the blade. The proposed deformation method, due to its simplicity, is suitable for the use of actuators. Different deflection angles are obtained at various wind speeds for each section through a controllable flap deformation method. The blade element momentum theory is used to calculate the performance of the morphing flaps. The results of this design are then validated by computational fluid dynamics (CFD) simulations using three‐dimensional Reynolds averaged Navier–Stokes equations together with the k–w turbulence model. The CFD results show that using optimum flap angles between 2° and 8° in the root, middle, and tip parts of the blade leads to a promising power increase of about 1.2%, 3.7%, and 13.5% at wind speeds of 4, 8, and 11.5 m/s.

Optimization of horizontal axis wind turbine performance with the dimpled blades by using CNN and MLP models

In this study, four NNs models are designed by three types of data: CFD data of original (no-dimpled), dimpled blades, and experimental data. These data are used to estimate torque and thrust. Models of the designed networks are Multilayer Perceptron (MLP) and the Convolutional Neural Network (CNN) so that the input of MLP is a vector and the input of CNN is a matrix. The networks are trained with the data ten times. Each training process obtains estimated torque and thrust with small errors. According to the MLP, the average error of MSE for estimating the torque test data is 4.64e-3 ±5e-4, and this error for estimating the thrust test data is 1.34e-3 ±5e-4, while these errors for CNN are 1.4e-3 ±5e-4, and 1.2e-3 ±5e-4 respectively. As a result, CNN models have better performance in comparison to MLP. Finally, the optimal point for the two networks that estimated the torque is obtained using a Maxnet network. The MLP network correctly finds the optimal point five times out of ten, and the CNN correctly finds the optimal point eight times out of ten, which is consistent with the CFD data. MLP and CNN estimate the torque and thrust with high accuracy, and the optimum point of the turbine is correctly recognized. Therefore, these models can be implemented to reduce the computational costs of CFD simulation.

A Comparative Study of the Influences of Leading-Edge Suction and Blowing on the Aerodynamic Performance of a Horizontal-Axis Wind Turbine

The aerodynamic performance of a National Renewable Energy Laboratory Phase VI horizontal-axis wind turbine (HAWT) equipped with blades characterized by leading-edge suction and blowing was analyzed numerically in three dimensions using computational fluid dynamics. The effects of leading-edge suction and blowing flow control methods on the flow field and aerodynamic characteristics of the HAWT and its performance were compared. The results suggest that leading-edge suction is superior to leading-edge blowing in suppressing the flow separation on the suction side of the turbine blade and improving the turbine aerodynamic characteristics. However, compared with the baseline turbine, the bending moment acting on the rotating blade of the HAWT to which suction or blowing is applied increased. This increment was greater for turbines with leading-edge blowing flow control blades. The effects of different arrangements of suction slots on the performance of the HAWT were analyzed. The results showed that the net wind power coefficient of the HAWT after deducting the energy consumption of the suction control was 45% higher than that of conventional turbines, indicating great potential for practical applications.

Study the effect of wind speed on the dynamic stall behavior of horizontal axis wind turbine performance characteristics during yaw misalignment using analytical approach

Study the effect of wind speed on the dynamic stall behavior of horizontal axis wind turbine performance characteristics during yaw misalignment using analytical approach

Aerodynamic Performance of a Horizontal Axis Wind Turbine Operating with Dust—A Computational Study

The main purpose of this study is to develop an understanding of the aerodynamic performance of a horizontal axis wind turbine (HAWT) operating in a dusty environment, with various concentration of dust in the flow domain. The computational analysis was accomplished by the commercial computational fluid dynamics (CFD) code ANSYS Fluent 16.0. Initially, a user-friendly developed application was utilized for the optimum blade geometry special characteristics calculation. The design of the HAWT rotor and meshing of the computational domain follows. The moving reference frame (MRF) model was applied for the rotary motion of the blades, the dust was added in the computational domain by the discrete phase model (DPM) and SST k–ω turbulence model was enabled. The power output of the studied HAWT, operating in several dusty environments, was estimated and compared with the power output of a particular HAWT in clean air. The flow field around the HAWT rotor, including the contours of pressure, particles dissipation rate and erosion rate on both blade sides, are shown. In general, it is concluded that the operation of a HAWT in a dusty environment results in degraded performance, due to the particles deposition on the blades.

Site-specific considerations for aerodynamic design upgrade of a wind turbine operating in a saharan environment

Sand erosion and dust deposition may induce surface irregularities of the blades of a wind turbine deployed in the Sahara, causing performance deterioration. In the current work a multi-objective optimization algorithm is developed to upgrade the aerodynamic blade profile of wind turbines operating in a Saharan environment. As a case study, the rotor of the Nordtank 300 kW horizontal axis wind turbine operating in Hurghada, Egypt is customized for lower sensitivity to surface roughness. The goal is to achieve a high lift-to-drag ratio while simultaneously maintain high resistance to dust deposition and sand erosion. The optimization algorithm is developed in MATLAB using C-language and coupled via ANSYS-ICEM to ANSYS-FLUENT computational fluid dynamics software for a particle-laden flow simulation until the optimization objectives are iteratively met. The optimization process yields a blade with lower sensitivity to surface roughness issues not only offsetting the 10.58% loss in Annual Energy Production (AEP) using the original profile, but actually boosting the AEP by 10.87% for the optimized blade. It is believed that this research may draw attention to the need for site-specific blade design to avoid environmental surface degradation as a result of dust deposition and sand erosion that may be unavoidable in the Saharan environment of countries in the MENA region.

The aerodynamic effects of blade pitch angle on small horizontal axis wind turbines

PurposeThe purpose of this paper is to thoroughly investigate the aerodynamic effects of blade pitch angle on small scaled horizontal axis wind turbines (HAWTs) using computational fluid dynamics (CFD) method to find out the sophisticated effects on the flow phenomena and power performance.Design/methodology/approachA small HAWT is used as a reference to validate the model and examine the aerodynamic effects. The blade pitch angle was varied between +2 and −6 degrees, angles which are critical for the reference wind turbine in terms of performance, and the CFD simulations were performed at different tip speed ratio values, λ = 2, 3, 4, 5, 6, 7, 9 and 10.5 to cover the effects in various conditions. Results are examined in two different aspects, namely, general performance and the flow physics.FindingsThe power performance varies significantly according to the tip speed ratio; the power coefficient increases up to a certain pitch angle at the design tip speed ratio (λ = 6); however, between λ = 2 and 4, the more the blade is pitched downwards, the larger is the power coefficient, the smaller is the thrust coefficient. Similarly, for tip speed ratios higher than λ = 8, the positive effect of the low pitch angles on the power coefficient at λ = 6 reverses. The flow separation location moves close to the leading edge at low tip speed ratios when the blade is pitched upwards and the also tip vortices become more intense. In conclusion, the pitch control can significantly contribute to the performance of small HAWTs depending on different conditions.Originality/valueIn the literature, only very little attention has been paid to the aerodynamic effects of pitch angle on HAWTs, and no such study is available about the effects on small HAWTs. The change of blade pitch angle was maintained at only one degree each time to capture even the smallest aerodynamic effects, and the results are presented in terms of the power performance and flow physics.

Study the effect of trailing edge flap deflection on horizontal axis wind turbine performance using computational investigation

Study the effect of trailing edge flap deflection on horizontal axis wind turbine performance using computational investigation

CFD Comparative Study on Bended and 2D Airfoils on HAWT Performance

The design of a conventional horizontal axis wind turbine (HAWT) is based on the aerodynamic characteristics of a two-dimensional (2D) airfoil. The rotational motion and the consequent aerodynamic effects, of HAWT’s rotor, do not guarantee an optimal design point that matches the 2D airfoil characteristics. The present work studies the diversion of the flow due to the spanwise velocity component in a rotating reference frame. It suggests that a slight deviation in the flow away from the chordwise direction could alternate the characteristics of the airfoil profile. A bended profile with a circular arc was extracted from a baseline rotating blade, flattened, and modelled against the 2D S826 airfoil. The results show a substantial discrepancy in the airfoil characteristics which could influence the turbine efficiency. Therefore, it suggests using a pre-bended airfoil (3D) while modeling the blade, so the circular section will match the correct airfoil coordinates. The proposed bended-profile version was modeled against the baseline blade. This novel blade shows an augmentation in the power coefficient up to 5.4% starting from the design point to high tip speed ratios (TSR) and low wind speeds.

Quantitative impact of a micro-cylinder as a passive flow control on a horizontal axis wind turbine performance

Adding micro-cylinder as a passive flow control is a new trend to enhance the power output of wind turbines. The impact of adding micro-cylinder, with different configurations, around horizontal axis wind turbine blade (HAWT) is examined using 3-dimensional simulations. The conventional turbine National Renewable Energy Laboratory (NREL Phase II) straight-bladed wind turbine is selected to validate the present numerical arrangements, where it hasn't been tested before with adding micro-cylinder. The Reynolds Average Navier-Stokes (RANS) equations for steady-state incompressible flow combined with Shear Stress Transport (k-ω SST) turbulence model are employed for the current numerical analysis. In this study, a parametric study is conducted for different diameters and locations of micro-cylinder. In total, seven cases are examined. The influence of micro-cylinder size is examined by changing the cylinder diameter (three different diameters, diameter/chord = 0.0131, 0.0175, 0.022). It has been found that the output power increases with decreasing the micro-cylinder diameter. The effect of micro-cylinder locations is investigated by introducing four different cases (four different locations around the leading edge). The power output increases for all cases. Additionally, it has been found that locating the micro-cylinder on the pressure side has less effect on the power output comparing to locating it on front of the blade leading edge.

Aeroelastic performance analysis of horizontal axis wind turbine (HAWT) swept blades

Over the past decades, the capacity of commercial wind turbines has risen from 50 kW with 10 to 15 m rotor diameter to 5 MW with more than 120 m rotor diameter. Conversely, increase in the rotor blade length causes substantial blade deflection in torsional, lead-lag and flap-wise directions which leads to unsteady aerodynamic load distributions. The structural safety and stability of the wind turbine will also be affected by the undesirable aerodynamic performance. It is important to analyze the aeroelastic performance of wind turbines under yaw conditions for large scale wind turbine design. Swept blade is a recent innovation to increase the power production of wind turbines while reducing the blade loads. There are insufficient studies in which the effect of yaw error on aeroelastic performance of Horizontal Axis Wind Turbine (HAWT) swept blade has been analysed yet. In this study, aeroelastic performance analysis was performed to investigate the effect of yaw angle on the aeroelastic performance of HAWT with swept blades. The same analysis was performed on HAWT unswept blade, so as to compare the results with that of HAWT swept blade. CFD analysis in ANSYS Fluent was chosen for aerodynamic analysis whereas FEA in ANSYS Static Structural was chosen for structural dynamic analysis. The aeroelastic performance analysis of wind-swept blades under yaw angles of 0°, 10°, 30° and 60° at wind speed of 10 m/s was performed. The results show that yaw error has negative effect on the aeroelastic performance of swept blade as well as unswept blade. It can be proven that swept blades have a better aeroelastic performance in terms of higher rotor power and lower deformation than unswept blades, i.e. higher stability of swept blades under yaw condition compared to unswept blades.

Konfigurasi Bilah NACA 3612 Terhadap Performa Turbin Angin Sumbu Horizontal (TASH)

To improve electrical energy better, the design and optimization of micro scale wind turbines has become a very important element in research. The aims are improving the ability to capture power and maximize energy production properly. The object of this study was horizontal axis wind turbine performance testing with the configuration of types and numbers of NACA 3612 blade variation in terms of output power (W), efficiency (η) and tip speed ratio (TSR). The tests carried out in the laboratory using a wind tunnel. There are 8 variations of wind speed, 1.41 m/s, 1.76 m/s, 2.51 m/s, 3.74 m/s, 4.81 m/s, 5.50 m/s, 5.71 m/s and 6.11 m/s. The results showed that the best power value was a taperless type with 2 blades of 0.846 watts with a maximum rotating speed of 876.3 rpm at 6.11 m/s wind speed. For the best efficiency value obtained at 3.74 m/s wind speed on the type of taper with a number of 4 blades of 2.9% at TSR 4.778. While the maximum TSR occurs in the type of taper with a number of 3 blades of 6.256 at 3.74 m/s wind speed by testing without using a prony brake.

Horizontal axis wind turbine modelling and data analysis by multilinear regression

Abstract. The modelling of each horizontal axis wind turbine (HAWT) differs due to variation in operating conditions, dynamic parameters, and components. Thus, the choice of profiles also varies for specific applications. So for the better choice of profiles, the wind turbine performance is analysed for different parameters and working conditions. The efficiency of HAWTs mainly depends on the blade, which in turn is related to the profile of the blade, blade orientation, and tip size. Hence, the main aim of the present work is to evaluate the performance of HAWTs for three different blade tip sizes and six different blade twist angles for three major NACA (National Advisory Committee for Aeronautics) airfoils. A statistical analysis is also carried out to find the influence of different performance parameters such as drag, lift, vorticity, and normal force. The static design parameters are considered based on the available literature. A three-bladed offshore HAWT is adopted as the research object in the study. Data visualization using star glyphs and sunray plots is performed, along with multilinear regression analysis. From the multilinear regression analysis and reliable empirical correlations, it is known that drag coefficient and lift coefficient parameters have less significance in contrast to the other parameters which have more significance in the regression model. The different results obtained in terms of parametric coefficients provide an effective way to generate appropriate airfoil profiles for given HAWTs. Thus, the study helps to achieve better turbine performance, and it serves as a benchmark for future studies on HAWTs.

Effect of Air-Ducted Blade Design on Horizontal Axis Wind Turbine Performance

Wind turbines without pitch control are more preferable from economical point of view but aerodynamic stall affects them more and after a critical wind speed local boundary layer separation occurs. Consequently, their power production is relatively low. In this study, air ducts added on the blade and using the airflow from them the kinetic energy of the low-momentum fluid behind the surface was increased and delay of separation of the boundary layer from the surface was examined The Response Surface Optimization method was utilized in order to get the best possible design under the constraints and targets arranged for the parameters termed the diameter, slope, number and angle of attack of the air ducts. By using computational fluid dynamics analysis, optimum parameter values were obtained and air-ducted and air-duct free blade designs were compared. An improvement in power coefficient between 3.4–4.4% depending on wind speed was achieved with the new design. Due to increase in viscous forces, more power from the rotor obtained by opening air ducts up to a critical number. However, the results showed that after the critical number of air duct addition of more duct on the blade reduced the power coefficient.

Effect of winglet geometry on horizontal axis wind turbine performance

Winglets (WLs) have recently been used to improve the performance of horizontal axis wind turbine (HAWT). The WL geometry is a key parameter for diverging blade tip vortices away from turbine blades and reducing induced drag. The present study focuses on the effect of winglet height (H) and toe angle (αw) on the turbine performance. The performance of a three‐bladed rotor of 1 m diameter with SD8000 aerofoil is numerically investigated using ANSYS 17.2 CFD on a polyhedral mesh. The model is hence validated by comparing results for power coefficient (Cpw) with experimental values available in the literature. Four different values of H are considered while keeping αw constant at 0°. H of 0.8%R is proved to be the best height for performance enhancement. It increases Cpw by 2.4% at tip speed ratio λ = 7. The toe angle effect is studied for upwind and downwind WLs. The results show that Cpw increases as αw increases up to αw = +20° at all values of λ. Cpw increases by 6% at λ = 7. Downwind WL always reduces Cpw. The present results are well explained by the resulting vectors map near the blade tip. Using WL with the optimum H and αw, causes 6% increase in Cpw as compared to rotor without WL.

Efficient contribution of partially tip cascaded horizontal-axis wind turbine

This article introduces novel blade tip geometric modification to improve the aerodynamic performance of horizontal-axis wind turbine by adding auxiliary cascading blades toward the tip region. This study focuses on the new turbine shape and how it enhances the turbine performance in comparison with the classical turbine. This study is performed numerically for National Renewable Energy Laboratory Phase II (non-optimized wind turbine) taking into consideration the effect of adding different cascade configurations on the turbine performance using ANSYS FLUENT program. The analysis of single-auxiliary and double-auxiliary cascade blades has shown an impact on increasing the turbine power of 28% and 76%, respectively, at 72 r/min and 12.85 m/s of wind speed. Knowing that the performance of cascaded wind turbine depends on the geometry, solidity and operating conditions of the original blade; therefore, these results are not authorized for other cases.

Investigation of a small Horizontal–Axis wind turbine performance with and without winglet

The objective of this study is to demonstrate computationally the effect of winglet length and cant angle on the performance of a small horizontal-axis wind turbine. The computational study was done using the ANSYS Fluent 15 software for a steady-state flow. Different designs of winglet with different lengths and cant angles were numerically studied and optimized using Artificial Neural Network (ANN). The winglet length was changed from 1% to 7% of the wind turbine rotor radius with cant angles from 150 to 900. The parameters of the wind turbine performance, which are power coefficient and thrust force coefficient were investigated for different winglet configurations. This was carried out from cut-in wind speed (3.12 m/s) to wind speed (12 m/s). It demonstrated that, there were noticeable enhancements in power and thrust coefficients in the presence of winglet. The best improvement in the performance was achieved when winglet length was 6.32% and cant angle 48.30. At this case, the percentage increase in power coefficient equals to the percentage increase in thrust coefficient which was 8.787%.