Wind Turbine Acoustic Control

A multi-axis wind turbine with integrated noise reduction that can capture and convert wind power while also significantly reducing the noise produced. The turbine has interconnected vertical blades that rotate around a central shaft. Above the blades is a chamber with sound absorption materials. When the blades spin, they transport noise into the chamber where it is absorbed. This allows the turbine to continue operating and generating power even when there is no wind, as it can release stored electrical energy. The interconnected blades allow for multi-axis rotation and wind capture compared to conventional horizontal axis turbines. The noise reduction chamber provides systematic noise management and reduction compared to traditional sound barriers.

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Modifying the sound emitted by wind turbines to reduce tonal noises that can be annoying to nearby residents. The method involves adjusting the fan rotational speeds to create fan sounds that mask the generator tone. This is done by setting fan speeds so the fan frequencies deviate from the generator frequencies by a small amount. The fan speeds are also chosen to avoid harmonics of the generator frequencies. This active masking prevents tonal superposition and makes the overall sound less objectionable.

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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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A wind farm noise and vibration reduction system that uses active noise control and passive noise control techniques to effectively reduce wind turbine blade noise and vibration. The system involves installing secondary sound sources on the wind turbine blades, collecting blade noise signals, and using adaptive filtering algorithms to generate control signals that drive the secondary sources to emit offsetting sound waves. Passive mufflers are also used to control mid- and high-frequency noise. This allows real-time adaptation to blade noise changes, improving noise reduction and energy savings without increasing blade resistance or impacting performance.

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Noise reduction device for wind turbine towers to mitigate the noise generated by the rotating blades as they pass the tower. The device changes the airflow direction around the tower to reduce impact and friction. It consists of rotating components mounted on the tower that affect the blade-driven airflow. The rotating components have noise-absorbing components inside. The device also has sliding plates that allow the rotating components to move together with the blades. This changes the blade-generated airflow to avoid direct impact on the tower.

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A noise reduction device at the bottom of a wind turbine tower that uses polyester fiber sound-absorbing panels to improve environmental protection and reduce noise without producing dust pollution compared to traditional resin glass wool. The device has soundproof walls installed around the air-cooled radiator at the base of the tower to dampen noise from the fan. The polyester fiber panels provide effective noise reduction without generating dust like glass wool.

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A wind turbine blade with rapid noise reduction by using internal and external noise reduction components attached to the blade. The blade has a mounting plate on one side connected to the fan and a hub on the other side. Inside the blade near the hub is a fixed tooth-shaped component with an air guide groove in its outer surface. The tooth component has a base layer fixed to the blade outer surface and a sound-absorbing layer on the base layer outer surface. A smooth layer covers the sound-absorbing layer outer surface. Near the hub, there is also a fixed mounting block with a threaded fixing groove. Inside the hub, there is a threaded mounting hole and bolts to connect the mounting block and hub. This internal noise reduction component reduces blade vibration noise. Externally, the blade has a tooth-shaped component with an air guide groove on its outer surface. This external component reduces wind

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Masking tonal noise from wind turbines by directing the masking noise away from the turbine axis to mitigate the tonal noise that is perceived by humans. The method involves generating directional masking noise from a turbine component like a noise generator, and aiming the masking noise in a direction that points away from the turbine's rotor axis. This allows the masking noise to partially cancel out the tonal noise while avoiding masking the beneficial low frequency noise that helps people perceive the turbine's presence. The masking noise direction can be adjusted as the turbine yaws.

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Controlling airborne tonal noise generated by wind turbine components like gearboxes by optimizing vibration control systems. The method involves selectively activating vibration control actuators based on wind turbine operating conditions to reduce component vibrations and tonal noise. This prevents unnecessary actuator usage and energy consumption for vibrations that don't lead to tonal noise. It also avoids situations where actuator oscillations reduce vibrations but increase tonal noise. The actuator selection and amplitude are adjusted based on machine learning or manual calibration to find the optimal trade-off between vibration reduction and tonal noise suppression.

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A multi-axis wind turbine with built-in sound absorption and power generation capabilities to reduce noise pollution from infrastructure projects like highways. The turbine has blades that interlock and rotate in response to wind force. The blades connect to a lower rotating mechanism and an upper sound chamber. The chamber has a sound-absorbing section and a sound-insulating section. The blades capture wind energy to turn the rotating mechanism and generate electricity. Wind-driven blade rotation transports noise into the upper chamber where it is absorbed and insulated. This reduces overall noise compared to just blocking sounds with barriers. The turbine provides continuous power and noise reduction.

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A noise reduction device for wind turbines that can be easily installed inside the nacelle to significantly reduce the noise generated by the generator. The device wraps around part of the generator to absorb and shield noise. It consists of interconnected support frames that fix to the generator inside the nacelle, with spaced damping units between the frames and generator. These cover and surround the generator to reduce noise through interference and absorption.

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Controlling wind turbine noise levels without sacrificing power output by optimizing add-on device usage. The method involves setting a target noise level and controlling the turbine's add-on aerodynamic devices to stay below that level while maximizing power generation. It limits the number of devices allowed to extend at once based on the noise requirements. This prevents reducing turbine speed or output power to lower noise.

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Active noise control for wind turbines to reduce noise levels near residential areas without shutting down the turbines. The method involves monitoring the noise levels in the surrounding sensitive areas and selectively adjusting the wind turbine operation to mitigate the noise. This is done by comparing the sensitive area noise levels to a background level and choosing a noise reduction control scheme based on that difference. The chosen scheme, like varying generator speed, is then implemented to reduce the wind turbine noise. The goal is to effectively reduce wind turbine noise without resorting to shutdowns or other measures that impact power generation.

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A wind turbine noise suppression system to mitigate wind turbine noise impact without affecting power generation. The system uses a positioning device, environmental noise sensor, sounding device, and controller in the turbine. The controller has a database with noise pollution avoidance zones around the turbine. The steps are: position the turbine to avoid noise zones, measure external noise, play a sound to match it, and adjust turbine operation if needed.

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Wind turbine blade noise reduction device that reduces blade noise while maintaining blade efficiency. The device uses noise reducing components that can move and reset when the blades rotate. The components include boards with holes and sponges that absorb noise when blown by the wind. Centrifugal force throws them out, but springs pull them back to protect the blades when stationary. This increases the blade area exposed to wind, improving efficiency.

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Noise reduction system for wind turbine blades that combines passive serrations with active sensors and actuators to significantly reduce trailing edge noise. The system uses sensors near the jagged edges to detect turbulent flow conditions. An actuator is controlled based on the sensor output to generate an anti-noise signal that cancels out some of the blade noise. This active noise cancellation complements the passive serrations to provide improved overall noise reduction compared to just using the serrations alone.

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Reducing noise and vibrations generated by wind turbines to mitigate their impact on nearby residents and wildlife. This involves improving the soundproofing of the tower to reduce harmful low frequency sounds and vibrations like infrasound. By reducing the propagation of these frequencies through the tower, it can help minimize the disturbance to people and animals in the surrounding area.

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Reducing noise from vertical axis wind turbines in built environments. The invention involves a sound attenuation arrangement for vertical axis wind turbines installed in urban areas. The arrangement includes fixed stator elements around the turbine rotor. These elements have sound absorbing material to dampen noise. The turbine, with its fixed stator elements, is installed in a structure like a building. This provides additional sound attenuation from the turbine. It aims to significantly reduce noise from vertical axis wind turbines in built environments.

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Active noise reduction for wind turbines that uses sensors and actuators on the blades and tower to cancel trailing edge noise. The system has unsteady pressure sensors on the blades to detect turbulent flow conditions. Noise sensors on the tower or nacelle measure blade noise. An adaptive filter controlled by a unit on the blades generates an anti-noise signal based on the sensor outputs. Actuators like speakers emit the anti-noise to counter blade noise. The filter adjusts based on blade orientation to optimize cancellation when the blade is downward.

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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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