Wind Turbine Blade Designs for Noise Reduction

Bionic wind turbine blade design that reduces noise without sacrificing aerodynamic performance. The blade has a non-smooth leading edge and a curved sawtooth trailing edge, especially at the middle to end sections of the blade. This bionic shape inspired by owl wings and feathers aims to significantly reduce aerodynamic noise generated by wind turbine blades while maintaining aerodynamic efficiency. The non-smooth leading edge and curved serrated trailing edge are applied to the noise source areas near the blade mid-span.

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Optimizing wind turbine blades for low air density sites to improve power generation without changing blade geometry. The technique involves adding sound protection features near the blade tip that increase induction factor at low air densities. The features are serrations with spikes along the blade edge. By upsizing the spikes, installing them at an angle, and adjusting their shape, the blade's effective trailing edge is altered to boost blade performance in low density conditions. This compensates for reduced lift and power from the lower air density without modifying the blade shape.

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Wind turbine blade noise reduction device that significantly reduces wind turbine blade noise compared to conventional noise reduction methods. The device has a wind turbine blade noise reduction body with a first noise reduction component on one side and a second noise reduction component on the other side. The first component has an inner blade, an air knife, an upper flow hole, and a lower flow hole. The air knife is fixed to the inner blade. The upper flow hole is at the top of the air knife and the lower flow hole is at the bottom. This disperses the airflow around the inner blade to reduce noise. The second component has a damping component attached to the end to further reduce vibrations and noise.

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Reducing noise from wind turbines by adding a dorsal fin-like structure at the blade tips. The fin extends vertically from the blade tip and has a curved shape that follows the blade profile. The fin reduces noise by breaking up the vortex shedding that occurs at the blade tips. This vortex shedding is a major source of noise from wind turbines. The fin disrupts the vortex shedding pattern, which reduces the noise emitted by the turbine. The curved shape of the fin matches the blade profile to maintain aerodynamic efficiency while still reducing noise.

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Low-noise wind turbine blade design that improves aerodynamic efficiency while reducing noise. The blade has an adjustable flap at the trailing edge made of acoustic metamaterial. The flap angle can be changed to increase lift at low wind speeds. The flap is also made of materials that absorb noise. By optimizing blade shape and adding noise-reducing flaps, the blade efficiency is increased while noise is reduced compared to traditional blades.

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Wind turbine blade design to reduce noise at the trailing edge. The blade has a noise reducing portion near the trailing edge with multiple acoustic resonators. Each resonator has an opening in the blade surface and a cavity with a length between the opening and bottom. The resonators absorb sound waves and mitigate trailing edge noise. The cavity length can be optimized for different frequencies. The resonators can have partition walls to divide the cavity into multiple parts. Some resonators can be covered with permeable layers. The resonators can be curved or slanted. The blade can have serrations with resonators.

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Low-noise wind turbine blade with adjustable flaps at the trailing edge that can be moved to change the blade shape and improve lift and efficiency at low wind speeds. The flaps have sound-absorbing acoustic metamaterials to reduce noise radiation compared to fixed blades. The flaps can be moved using a drive mechanism to adjust the blade angle of attack. This allows optimizing blade shape for low wind starts and reducing noise pollution.

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Wind turbine blade design with a noise reducer to mitigate trailing edge noise. The noise reducer comprises aligned spine members on the blade trailing edge. Each spine has a stiff first section and a flexible second section. Adjacent spines are connected at the stiff sections but not at the flexible sections. This creates a rigid structure followed by flexible sections. The stiff sections provide stability while the flexible sections allow deformation to reduce noise.

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Wind turbine blade design with internal damping elements to reduce noise and vibration during operation. The blades have cushioning elements extending from the interior surface to absorb impacts and vibrations. This prevents debris falling inside the blade from striking the interior surface and generating noise. The cushioning elements also reduce structural damage from internal debris impacts. The blades can further have acoustic dampening elements to absorb noise propagation through the blade interior.

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A low-speed, low-noise wind turbine blade design for urban areas with low rotor speeds to mitigate noise and vibration issues. The blade has a maximum tip speed of 100 km/h or less, regardless of wind speed. The blade shape has a covered metal suction panel on one side, rather than fully occupying the side. This reduces drag and noise compared to fully enclosed blades. The covered metal structure allows fossil fragments inside to reduce noise further. The reduced tip speed and unique blade shape enable low-noise, low-speed urban wind power generation.

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Retrofit system for a wind turbine blade that reduces noise generated by wind turbine blades. The system includes a trailing edge, a mounting structure, and at least one serrated portion extending at least partially along the mounting structure.

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Noise reduction structure for wind turbine blades that reduces blade noise without sacrificing strength. The structure has a series of teeth along the blade trailing edge. The teeth are connected by a reinforcement portion. The teeth length increases from root to tip. This shape changes the blade trailing edge profile to avoid shedding vortices that cause noise. The reinforcement divides the teeth into sections. The triangular tooth edge enhances noise reduction. The teeth structure reduces broadband scattered noise compared to sharp edges.

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Noise reduction device for wind turbine generators to mitigate the high noise levels produced during operation. The device uses an optimized blade shape, internal sound insulation, and heat dissipation to reduce noise. The blade tips have triangular structures with grooves that concentrate air flow and reduce noise compared to plain tips. Inside the generator, upper and lower insulation layers surround the components. An embedded fan draws heat. The generator housing has a vertical hole for sound entry. An inclined plate and angled hole direct sound into the stator. This concentrates noise into the stator core instead of radiating externally. The vertical plate with sound entry hole further reduces noise. The optimized blade tips, internal insulation, heat dissipation, and sound entry/directing features all work together to significantly reduce wind turbine generator noise.

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A wind turbine blade design with integrated noise reduction that addresses the limitations of prior art noise reducers. The blade has a noise reducer attached near the trailing edge. The noise reducer has a base plate with openings. The noise reduction devices extend from the base line and are arranged symmetrically on opposite sides of the base line. This allows accurate and efficient positioning of the noise reduction devices on the blade without additional mounting hardware. The blade itself defines the blade angle axis.

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Wind turbine blade design with a porous media on the trailing edge to reduce noise without sacrificing aerodynamic performance. The porous media allows internal flow circulation and increases boundary layer thickness compared to a solid trailing edge. This reduces noise sources and pressure pulsations in the trailing edge area. The porous media can be metallic or non-metallic. The porous section length is limited to avoid excessive aerodynamic losses. The porous media increases surface roughness and flow complexity, but only at the trailing edge.

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Blade design for wind turbines that reduces noise levels compared to conventional blades. The blade has serrated teeth on the trailing edge near the tip. The teeth are angled towards the blade tip direction. This configuration reduces aerodynamic noise by breaking up the airflow and preventing large pressure differences that can cause noise. The angled teeth align with the flow direction at that location. This optimizes noise reduction compared to parallel serrations.

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A wind turbine blade design to reduce noise generated by wind turbines. The blade has a noise reduction mechanism at the rear tip. It consists of an extension joint, flap, and noise reduction tooth. The flap and tooth decompose the boundary layer of airflow to reduce noise. The flap connects to the extension joint at the blade tip. The tooth extends from the flap. This design reduces trailing edge noise of the blade.

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Noise reduction structure for wind power blades that reduces blade trailing edge noise without compromising blade strength. The structure has a spoiler connected to the blade by a transition piece. The spoiler disturbs the airflow at the trailing edge to break up boundary layers and reduce turbulence. The transition piece allows the spoiler to bend with the blade without stress concentrations. The spoiler thickness gradually reduces away from the transition. This matches blade bending and enhances turbulence.

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Reducing tonality in wind turbine blades to improve noise performance by strategically thickening the blade near the trailing edge. This involves creating a local maximum in thickness at the blade tip end to mask tonal frequencies. The thickening is done on the suction or pressure side or both, and extends between 20-50% of the blade depth. This masking effect makes tonal frequencies less noticeable by blending them into the broader noise spectrum.

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Environmentally friendly low-noise wind power generator that reduces noise during operation compared to conventional wind turbines. The noise reduction is achieved by modifying the wind wheel design to prevent periodic low-frequency sounds and sealing the generator and gearbox to reduce noise transmission. The wind wheel has a deflector with blades and grooves that prevent periodic airflow patterns. The blades have preformed grooves with limit rods and movable panels that prevent airflow stall. The movable panels have countersunk grooves with buffer pads to absorb impacts. The generator and gearbox are sealed inside the unit housing to prevent noise transmission. This reduces low-frequency noise propagating outward during operation, making the wind turbines quieter and more suitable for closer placement near people.

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