Aerodynamic Blade Designs for Wind Turbines

Wind turbines align with the wind direction and adjust to speed by rotating their nacelle blades using electromechanical or hydraulic actuators. Due fact that rated capacity of is increasing actuators are reaching some size limits, current solution install several at each joint until required torque reached. The problem this approach that, despite can be selected from same type series, they typically have distinct parameters, resulting in different behaviours. synchronisation has still not been studied specialised literature. Therefore, a control for pitch proposed work. Two cases considered: outputs position angle. simulation results indicate effective synchronising actuators, either when placed together on blade separate while simultaneously following collective command.

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This study investigates the impacts of surging and pitching motions on power generation performance wake characteristics an IEA 15 MW offshore wind turbine under specific inflow conditions. The three-dimensional, unsteady continuity equation, momentum equations, SST k turbulence model are solved numerically using computational fluid dynamics software STAR-CCM+ (version 2206) to simulate aerodynamic flow field around rotor in its downstream region. Under condition speed 9 m/s at hub height a corresponding rotational 7.457 RPM, prescribed by sinusoidal functions with period 45 s amplitudes 2.75 m 5, respectively. analyzes quantifies output over duration 200 revolutions, considering stationary, surging, results indicate that cause reductions mean 2.18% 3.54%, respectively, compared stationary condition. also lead significant enhancement region, minimum spacing turbines is suggested.

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As the utilization of wind energy continues to expand as a prominent renewable source, application Darrieus Vertical Axis Wind Turbine (VAWT) technology has expanded significantly. Various passive modification methods have been developed enhance efficiency and optimize aerodynamic performance rotor through blade modifications. This study presents method utilizing KlineFogleman (KF) blades which incorporate step-like horizontal slats along trailing edge. Through Computational Fluid Dynamics (CFD) simulations, this evaluates ten distinct KF configurations, varying in step length depth, with steps positioned on inner side, outer both sides airfoil. The results indicate that shorter 20%c 2%c enhances average power coefficient (Cp) by 19% compared clean blade. However, when are incorporated blade, dimensions 50%c 5%c Cp decreases 33% reduction occurs across low high tip speed ratio (TSR) ranges. It observed presence high-pressure zone 200 Pa at edge disrupts is upwind region between azimuth angles 45 135.

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Rotor blades for wind turbines with high lift root profiles that have flat backs and optimized design for improved efficiency and energy yield. The profiles have thick airfoil sections near the root with moderate trailing edge thickness, curved suction sides, and maximum thickness located behind 30% chord length. This allows high inflow velocity for vortex generators, laminar flow, and delayed stall. It balances thick root profiles with reduced trailing edge height and pushed max thickness.

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Wind turbine blade design with offset flexible and stiff add-on elements to improve aerodynamics while facilitating handling. The blade has a mix of flexible and stiff add-on elements arranged offset in span and chord directions. The flexible elements are made of elastic materials like rubber to absorb impacts during handling. The stiff elements are made of stiffer materials. This allows protecting the flexible elements during blade handling without constraining their placement. The offset arrangement of flexible and stiff elements also improves blade aerodynamics by reducing drag and increasing lift compared to using all flexible or all stiff add-ons.

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This paper presents a numerical study of the optimization geometric parameters four-bladed Darrieus vertical-axis wind turbine (VAWT) with NACA 0021 aerodynamic profile. The aim was to increase efficiency by selecting optimal values rotor diameter and blade chord length. Taguchi method using an orthogonal array used as method, which reduced number necessary calculations from 77 20 while maintaining reliability analysis. CFD modelling performed in ANSYS 2022 R2 Fluent software environment based on two-dimensional non-stationary model, including full revolution analysis steady-state mode for twentieth cycle. As result analysis, were determined: D = 3 m length c 0.4 m. Additionally, selected configuration, model validated constructing dependence power coefficient Cp tip speed ratio range 0.2 2.8. maximum value 0.35 at 2.2, is ~64% compared least efficient rotation considered . obtained results allow us conclude that can be combination fast accurate low-power turbines.

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Introduction Swept blades can achieve effective load reduction, thereby improving the operational performance of wind turbines. To investigate impact hundred-meter-level swept on characteristics turbines, this paper takes IEA-15 MW turbine as subject. Methods Based free-wake lifting line theory model and geometrically exact beam model, straight under rated conditions are compared. Results discussion The results show that undergo greater torsional deflection, reducing angle attack achieving reduction. influence different sweep parameters is also discussed. study finds reduction effects starting point index similar, while effect displacement most significant, it becomes more pronounced increases. Additionally, yaw conditions, increases, gradually increasing deflection decreasing amplitude flapwise speed fluctuation lead to a downward trend in both mean attack.

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As the blade size of wind turbine ascends, potential flutter issue has become a crucial factor in safety design turbines. The high flexibility and strong nonlinearity result possibility for ultra-large horizontal axis blades even at low rotor speed. With IEA 15 MW as research object, dynamic model aeroelastic system was established. Research on response during rotational speeds multi-degree-of-freedom coupling characteristics therein conducted. results indicate that under operating conditions speed speed, can undergo coupled involving flapwise-edgewise-torsional coupling. Only edgewise-torsional are presented frequency domain. However, from energy perspective, it is found maintained by combined work aerodynamic forces all three degrees freedom. Different segments contribute differently, middle section tip make main contribution. There exists distinct phenomenon development instantaneous power each degree

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The design of the wind turbine blades has a significant impact on operation turbine. Therefore, cross-sectional structure airfoil needs to be simulated by specialized software evaluate performance turbine, especially in low speed region. This paper studies aerodynamic characteristics such as lift coefficient (CL), drag (CD) and ratio (CL/CD) attack angle ranges from -8 degrees 10 S4110 model under velocity (3 m/s) using QBLADE XFLR5 with Reynolds margin conditions 200000, Mach 0.3 Ncit 9. Evaluate ability analyze parameters. purpose study is verify accuracy two comparing simulation results experimental data Airfoiltool. showed that both achieve high at small angles (from -4.5 4 degrees), an error less than 5%. Besides, optimal determined value Ratio 80.02

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A wind turbine blade design with an access window that allows internal blade components to be accessed and replaced without disassembling the entire blade. The blade has a framed opening in the outer shell that aligns with an internal access window. A removable cover seals over the framed opening. This provides a controlled access point to the interior without needing to cut into the blade shell. The cover is attached separately to the blade and frame, allowing it to be opened at height. This enables maintenance tasks on internal components like spars without removing the blade. The blade segments are joined and sealed separately after accessing the components.

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When developing a system for power production it is of interest to be able optimize design features create the maximum electrical output. It expensive both physical models these systems and iterate upon them improve on aspects. Digital are useful in this case as they inexpensive run easily changed fly. Researchers at UNC Charlotte have developed model 100 kW rated wind turbine explore how rotor diameter gear ratio affect performance such system. The digital uses an input National Renewable Energy Lab (NREL) resource data over range 3 years between 2004 2006 with fixed blade pitch, air density. finds given that 20.6 17.86m optimal. This allows engineers estimate generation speed from database determine best parameters before construction begins. can further include economic factors levelized cost energy ensure feasibility standpoint.

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A method to manufacture wind turbine blades that improves alignment and bonding of shear webs between the inner shell surfaces. The method involves attaching the shear web to one shell half, then bringing the other half together while guiding the shear web over pairs of angled guide members on the inner surface of the second shell half. This prevents rotation and twisting during bonding. The guide members form a funnel shape that aligns the shear web as it's inserted into the other shell half. The guide members are removable spacers during assembly that are later removed. The guide members can be extruded or injection molded parts with hollow bodies and angled surfaces.

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Root assembly design for wind turbine blades that improves blade strength and fatigue life without increasing blade diameter. The root assembly has a staggered configuration of bolts and bushings in the blade root. The bushings are offset axially so adjacent bushings are spaced farther apart than just alternating them. This prevents high strain concentration between adjacent bolt cavities. The offset axial distance between centerlines of adjacent bushings is at least 2.5 times the bushing diameter. This balanced spacing reduces stress concentration and strain bias through the blade laminate.

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Wind turbine blade design to reduce aerodynamic noise without impacting power generation. The blades have a specific solidity distribution along the blade radius that allows lower tip speeds without reducing lift force. The blade geometry is optimized to reduce noise at high tip speeds, which are common in large wind turbines. The specific solidity at 70%, 80%, and 90% of the blade radius must meet certain thresholds to achieve the noise reduction. This allows lower tip speeds for less noise without reducing power output.

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This study explores a novel morphing blade design methodology to enhance the aerodynamic performance of NREL 1.5 MW wind turbine while addressing structural constraints. The proposed approach applies targeted leading and trailing edges sections, utilizing streamlined parameterization framework with four shape variables per airfoil: two deflection angles deformation starting points. process is modeled using an m-degree function optimized genetic algorithm maximize power generation minimizing displacement thrust forces. Turbine initially assessed Blade Element Momentum (BEM) theory validated through high-fidelity Computational Fluid Dynamics (CFD) simulations based on Reynolds-Averaged NavierStokes (RANS) equations k- turbulence model. Results demonstrate significant coefficient improvements up 23.8%, 10%, 7% at speeds 11.5 m/s, 8 4 respectively, compared baseline configuration. These findings highlight potential technologies improve energy efficiency in turbines adhering practical limitations.

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Jointed wind turbine blade design with modified spar cap configuration to improve structural integrity of the blade joints. The blade has segments connected by internal joint structure. The spar caps in one segment have center sections with constant width and flared wing sections with decreasing width. The center sections are made of higher rigidity material than the wings. This allows the wings to have lower rigidity, making the overall spar cap rigidity less than the center section. This reduces weight while maintaining strength at the joint connection point.

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The increasing size of wind turbine blades poses several challenges, including higher manufacturing costs, transportation difficulties, and exacerbated aeroelastic phenomena. Optimizing both the aerodynamic structural performance large-scale is essential for addressing these issues. Traditional computational fluid dynamics (CFD)-based optimization methods are hindered by low efficiency, necessitating development more efficient, high-fidelity approaches. In this study, a neural network (NN)-based approach proposed to tackle challenges. First, class function/shape function transformation method introduced, inspired conventional airfoil parameterization method. This applicable distribution blade chord length twist angle, reducing number variables 10 MW from 82 22, while enhancing smoothness sampled blades. Second, comprehensive method, integrating developed. framework comprises two primary components: optimization. Each component follows four-step: geometric sampling, CFD-based dataset generation, NN training prediction, Finally, effectiveness validated using as benchmark. Results show ... Read More

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A new wind turbine blade design that aims to improve efficiency, reduce costs, and simplify manufacturing compared to conventional wind turbine blades. The key feature is replacing the fixed blades with aerodynamic elements (ADEs) that can rotate independently around the turbine shaft. The ADEs are made up of segments connected by spokes and have curved shapes optimized for specific air flow speeds. This allows the ADEs to align better with the wind as they rotate, reducing air resistance and increasing energy capture. The spoke extensions beyond the ADE tips provide lightning protection. The modular design enables easier transportation and assembly compared to large fixed blades.

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A multi-blade wind turbine rotor that instantly adjusts blade pitch angles based on wind speed to optimize performance over a wide range of wind conditions. The blades can rotate in a range from 0 to 45 degrees relative to the fixed outer ring they are attached to. This allows the blades to automatically find the best lift-to-drag ratio for the current wind speed. In high winds, a braking mechanism engages to slow or stop the rotor to prevent overspeeding. The split design allows large diameter rotors to be assembled and disassembled for transport.

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Wind turbine blade design with flexible tips that change orientation as wind speed increases to improve efficiency and reduce loads. The blades have flexible tips that initially tilt towards the blade rotation direction at low speeds, preventing vortex formation. As wind speed increases, the tips gradually tilt away from the rotation direction, reducing aerodynamic loads. The flexible tips are made of materials that deform with airflow forces. The blades are used on wind turbines to capture more power at medium speeds and reduce loads at high speeds compared to rigid tips.

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