Search

US-20260125152-A1 - ROTOR AND ROTORCRAFT

US20260125152A1US 20260125152 A1US20260125152 A1US 20260125152A1US-20260125152-A1

Abstract

A rotor includes a blade, a plurality of protruding structures protrude from the surface of the blade, the plurality of protruding structures are sequentially arranged at intervals in the spanwise direction of the blade, and a height difference is formed between every two adjacent protruding structures.

Inventors

  • Longzhi ZHAO
  • Lijun Xu
  • Yifei Zhang
  • Tianming Zhao

Assignees

  • BEIJING SANKUAI ONLINE TECHNOLOGY CO., LTD.

Dates

Publication Date
20260507
Application Date
20230711
Priority Date
20221226

Claims (20)

  1. 1 . A rotary wing, comprising a blade, wherein a plurality of protruding structures are arranged on a surface of the blade, the plurality of protruding structures are sequentially arranged at intervals in a spanwise direction of the blade, and a height difference is provided between adjacent protruding structures.
  2. 2 . The rotary wing according to claim 1 , wherein a height of the plurality of protruding structures is sequentially reduced in the spanwise direction of the blade to form a stepped distribution.
  3. 3 . The rotary wing according to claim 2 , wherein a height difference between a protruding structure closest to a rotation center of the blade and a protruding structure farthest from the rotation center is 0.1 mm.
  4. 4 . The rotary wing according to claim 1 , wherein the protruding structures are polygonal bosses.
  5. 5 . The rotary wing according to claim 4 , wherein each polygonal boss comprises a front portion, wherein the front portion has a triangular cross section.
  6. 6 . The rotary wing according to claim 5 , wherein an inner angle closest to a leading edge of the blade in a triangle is greater than or equal to 30° and less than or equal to 90°.
  7. 7 . The rotary wing according to claim 1 , wherein a height of the protruding structures satisfies: t = k ⁢ c Re 0.2 , wherein t is the height of the protruding structures; and k is a proportionality coefficient, and k ranges from 0.01 to 0.2; c is a local chord length; and Re is a local Reynolds number.
  8. 8 . The rotary wing according to claim 7 , wherein the local Reynolds number satisfies the following requirement: Re = ρω ⁢ rc μ , wherein ρ is an air density; ω is a rotational angular velocity of the blade; r is a local spanwise position; and μ is aerodynamic viscosity.
  9. 9 . The rotary wing according to claim 8 , wherein the local Reynolds number is greater than or equal to 10000, and less than or equal to 500000.
  10. 10 . The rotary wing according to claim 1 , wherein the protruding structures have a chordwise length greater than or equal to 0.05c and less than or equal to 0.2c, wherein c is a local chord length.
  11. 11 . The rotary wing according to claim 1 , wherein a ratio of a spanwise width of the protruding structures to a chordwise length of the protruding structures is greater than 0.01 and less than 0.2.
  12. 12 . The rotary wing according to claim 1 , wherein a ratio of spacing between adjacent protruding structures to a spanwise width of the protruding structures is greater than 0.1 and less than 2.
  13. 13 . The rotary wing according to claim 1 , wherein spacing between the protruding structures and a leading edge of the blade is greater than or equal to 0.05c and less than or equal to 0.5c, wherein c is a local chord length.
  14. 14 . A rotary wing aircraft, comprising a rotary wing, wherein the rotary wing comprises a blade, a plurality of protruding structures are arranged on a surface of the blade, the plurality of protruding structures are sequentially arranged at intervals in a spanwise direction of the blade, and a height difference is provided between adjacent protruding structures.
  15. 15 . The rotary wing aircraft according to claim 14 , wherein a height of the plurality of protruding structures is sequentially reduced in the spanwise direction of the blade to form a stepped distribution.
  16. 16 . The rotary wing aircraft according to claim 15 , wherein a height difference between a protruding structure closest to a rotation center of the blade and a protruding structure farthest from the rotation center is 0.1 mm.
  17. 17 . The rotary wing aircraft according to claim 14 , wherein the protruding structures are polygonal bosses.
  18. 18 . The rotary wing aircraft according to claim 17 , wherein each polygonal boss comprises a front portion, wherein the front portion has a triangular cross section.
  19. 19 . The rotary wing aircraft according to claim 18 , wherein an inner angle closest to a leading edge of the blade in a triangle is greater than or equal to 30° and less than or equal to 90°.
  20. 20 . The rotary wing aircraft according to claim 14 , wherein a height of the protruding structures satisfies: t = kc Re 0.2 , wherein t is the height of the protruding structures; and k is a proportionality coefficient, and k ranges from 0.01 to 0.2; c is a local chord length; and Re is a local Reynolds number.

Description

The disclosure claims the priority to Chinese Patent Application No. 202211679092.1, filed on Dec. 26, 2022 and entitled “rotary wing and rotary wing aircraft”, which is incorporated in its entirety herein by reference. TECHNICAL FIELD The disclosure relates to the technical field of aircrafts, and in particular to a rotary wing and a rotary wing aircraft. BACKGROUND A rotary wing aircraft is capable of vertical take-off and landing and low-altitude flight. With particular flight advantages, it has been widely applied to military and civilian fields, and will function as a dominant vehicle of urban air traffic in future. SUMMARY An objective of the invention is to provide a rotary wing and a rotary wing aircraft, so as to solve the technical problem in the related art and improve a noise reduction effect of the rotary wing. In a first aspect, the disclosure provides a rotary wing. The rotary wing includes a blade, where a plurality of protruding structures are arranged on a surface of the blade in a protruding manner, the plurality of protruding structures are sequentially arranged at intervals in a spanwise direction of the blade, and a height difference is provided between adjacent protruding structures. As described in the above rotary wing, a height of the plurality of protruding structures is sequentially reduced in the spanwise direction of the blade to form a stepped distribution. As described in the above rotary wing, a height difference between a protruding structure closest to a rotation center of the blade and a protruding structure farthest from the rotation center is 0.1 mm. As described in the above rotary wing, the protruding structures are polygonal bosses. As described in the above rotary wing, each polygonal boss includes a front portion, where the front portion has a triangular cross section. As described in the above rotary wing, an inner angle closest to a leading edge of the blade in a triangle is greater than or equal to 30° and less than or equal to 90°. As described in the above rotary wing, a height of the protruding structures satisfies: t=kcRe0.2,wheret is the height of the protruding structures; andk is a proportionality coefficient, and k ranges from 0.01 to 0.2;c is a local chord length; andRe is a local Reynolds number. As described in the above rotary wing, where the local Reynolds number satisfies the following requirement: Re=ρω⁢rcμ, where ρ is an air density;ω is a rotational angular velocity of the blade; andr is a local spanwise position; andμ is aerodynamic viscosity. As described in the above rotary wing, the local Reynolds number is greater than or equal to 10000, and less than or equal to 500000. As described in the above rotary wing, the protruding structures have a chordwise length greater than or equal to 0.05c and less than or equal to 0.2c, where c is a local chord length. As described in the above rotary wing, a ratio of a spanwise width of the protruding structures to a chordwise length of the protruding structures is greater than 0.01 and less than 0.2. As described in the above rotary wing, a ratio of spacing between adjacent protruding structures to a spanwise width of the protruding structures is greater than 0.1 and less than 2. As described in the above rotary wing, spacing between the protruding structures and a leading edge of the blade is greater than or equal to 0.05c and less than or equal to 0.5c, where c is a local chord length. In a second aspect, the disclosure further provides a rotary wing aircraft. The rotary wing aircraft includes the above rotary wing. Compared with the related art, in the disclosure, the plurality of protruding structures are sequentially arranged at intervals in the spanwise direction of the blade, and a contact region with air is increased by means of the plurality of protruding structures having the height difference to achieve forced turbulence transition on a laminar separation bubble of the blade, such that an air flow is more closely attached to the surface of the blade, and a thickness of a boundary layer of a trailing edge is reduced. Thus, an occurrence region of noise is reduced, and the purpose of reducing the noise is achieved. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an overall structure of a rotary wing according to an embodiment of the disclosure; FIG. 2 is a front view of an overall structure of a rotary wing according to an embodiment of the disclosure; FIG. 3 is a schematic structural diagram of a local position of a rotary wing according to an embodiment of the disclosure; and FIG. 4 is a perspective view of a protruding structure of a rotary wing according to an embodiment of the disclosure. Description of reference numerals: 1—blade, 2—protruding structure, 3—main blade, 4—blade tip, 5—leading edge, 6—trailing edge, 7—front portion, and 8—recess. DETAILED DESCRIPTION OF THE EMBODIMENTS The embodiments described below with reference to the accompanying drawings are exemplary a