# How Tiny Bumps on Wind Turbine Blades Reduce Noise > This patent describes how small, specially shaped bumps or grooves on a wind turbine blade's underside can reduce noise by controlling airflow and preventing turbulence. - **Patent:** US 10400744 - **Original title:** Wind turbine blade with noise reducing micro boundary layer energizers - **Owner:** General Electric - **Granted:** 2019 - **Status:** Active - **Times cited:** 5 - **Field:** energy, mechanical, aerospace ## What it does This patent covers a wind turbine blade assembly that includes small features called "micro boundary layer energizers" on its pressure side. These energizers, which can be vanes, grooves, dents, or dimples (Claim 1), are placed in a specific "outboard area" of the blade, between 0% and 50% of the blade's length from the tip (Claim 1). Their job is to create small swirls of air, called "longitudinal vortices," that mix the air near the blade's surface (Claim 1, Claim 2). This mixing helps the airflow stick to the blade longer, delaying "separation of a boundary layer" at low angles of attack (Claim 1). By doing this, the energizers reduce unwanted noise generated by the blade. For example, a wind turbine blade might have a series of 1-15mm high wedge-shaped bumps (Claim 6, Claim 10) positioned 20-55% of the way back from the leading edge (Claim 1) to smooth the airflow. ## What it does NOT cover - It does not cover micro boundary layer energizers placed on the suction side of the rotor blade. - It does not cover energizers positioned in the inboard portion of the blade, only the outboard area between 0%-50% from the blade tip (Claim 1). - It does not cover energizers placed downstream from the start of a "separation bubble" (Claim 1). - It does not cover energizers that are not specifically shaped and positioned to delay boundary layer separation at a low angle of attack (Claim 1). - It does not cover energizers with x/c ratios outside the 20-55% range (Claim 1). ## The clever bit The novelty lies in precisely shaping and positioning these tiny "micro boundary layer energizers" on the *pressure side* of the blade to specifically generate longitudinal vortices. This targeted approach delays airflow separation at low angles of attack, which directly reduces aerodynamic noise without significantly impacting performance. ## Real-world examples 1. Modern large-scale wind turbine blades 2. GE Renewable Energy wind turbines 3. Aerodynamic noise reduction features on aircraft wings ## Why it matters Wind turbines are a key part of renewable energy, but noise can be a significant issue for nearby communities. This patent offers a way to make wind turbines quieter by improving how air flows over the blades. Reducing noise allows wind farms to be located closer to populated areas or to operate more efficiently without causing disturbances, potentially increasing the adoption of wind power. ## Frequently asked questions ### What does How Tiny Bumps on Wind Turbine Blades Reduce Noise cover? This patent describes how small, specially shaped bumps or grooves on a wind turbine blade's underside can reduce noise by controlling airflow and preventing turbulence. ### Who owns patent US 10400744? General Electric owns this patent, granted in 2019. ### When does this patent expire? This patent is expected to expire on April 28, 2036, when the invention enters the public domain. ### What is patent US 10400744 cited by? This patent has been cited by 5 later patents that build on its ideas. ### What problem does this patent solve? Wind turbines are a key part of renewable energy, but noise can be a significant issue for nearby communities. This patent offers a way to make wind turbines quieter by improving how air flows over the blades. Reducing noise allows wind farms to be located closer to populated areas or to operate more efficiently without causing disturbances, potentially increasing the adoption of wind power. ### What does this patent NOT cover? It does not cover micro boundary layer energizers placed on the suction side of the rotor blade. **Full plain-English explainer:** https://patentbrief.org/patent/us/10400744/wind-turbine-blade-with-noise-reducing-micro-boundary-layer-energizers **Original patent:** https://patents.google.com/patent/US10400744 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [How Wind Turbine Blades Reduce Noise with Small Fins](https://patentbrief.org/patent/us/7927078/wind-turbine-blade-tip-vortex-breakers) — This patent describes how small, flat fins attached to the tips of wind turbine blades can reduce noise and improve efficiency by managing swirling air, called vortices. - [Wind Turbine Blades with Noise-Reducing Serrated Edges](https://patentbrief.org/patent/us/8932024/wind-turbine-blade-and-wind-power-generator-using-the-same) — This patent describes a wind turbine blade design that reduces noise by attaching a special serrated plate to its trailing edge, integrated directly into one of the blade's outer surfaces. - [How Wind Turbine Blades Get More Lift with Extra Parts](https://patentbrief.org/patent/us/8303250/method-and-apparatus-for-increasing-lift-on-wind-turbine-blade) — This patent describes adding special front and back parts to a wind turbine blade to create specific air channels, making the blade generate more power from the wind. - [Wind Turbine Blades with a Deeply Curved Front Surface](https://patentbrief.org/patent/us/7614852/wind-turbine-blade-and-assembly) — This patent describes a wind turbine blade designed with a deeply curved, concave front surface and a high camber ratio to potentially capture more wind energy. - [How a Wind Turbine Shroud Can Adjust Its Blades to Control Power](https://patentbrief.org/patent/us/20140030059/fluid-turbine-with-variable-pitch-shroud-segments) — This patent describes a wind turbine design where a ring-shaped casing around the main rotor has small, adjustable blades that can change their angle to control how much wind hits the rotor and how much power is generated.