US 12,276,250 B2
Noise reducing wind turbine blade
Andreas Herrig, Salzbergen (DE); Trevor Howard Wood, Schenectady, NY (US); and Guannan Wang, Salzbergen (DE)
Assigned to LM WINDPOWER A/S, Kolding (DK)
Appl. No. 18/286,886
Filed by LM WIND POWER A/S, Kolding (DK)
PCT Filed May 3, 2022, PCT No. PCT/EP2022/061761
§ 371(c)(1), (2) Date Oct. 13, 2023,
PCT Pub. No. WO2022/233815, PCT Pub. Date Nov. 10, 2022.
Claims priority of application No. 21172504 (EP), filed on May 6, 2021.
Prior Publication US 2024/0384700 A1, Nov. 21, 2024
Int. Cl. F03D 1/06 (2006.01)
CPC F03D 1/06495 (2023.08) [F03D 1/0675 (2013.01); F05B 2240/3042 (2020.08); F05B 2260/96 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A wind turbine blade having a profiled contour and comprising a pressure side and a suction side, a leading edge and a trailing edge, a chord having a chord length extending between the leading edge and the trailing edge, the blade extending in a spanwise direction between a root end and a tip end and having a longitudinal axis,
wherein at least a portion of the blade located in a trailing edge region at or adjacent to the trailing edge is a noise reducing portion defining an exposed surface and comprising a plurality of sound reducing or sound absorbing acoustic resonators, each of the resonators comprising an opening in the exposed surface and a cavity having a length between the opening and a bottom of a bottom wall of the cavity opposite the opening, the opening to the cavity having an opening cross-sectional shape defining an opening cross-sectional area and the cavity having a cavity cross-sectional shape defining a cavity cross-sectional area,
wherein the cavity of at least one resonator of the plurality of resonators is slanted in span wise direction relative to the local chord, and/or
wherein at least one of the plurality of resonators is curved and comprises a cavity having a cavity axis being curved for obtaining a desired length of the cavity.