CN114278494A

CN114278494A - Whale tail fin-imitated lift-increasing noise-reducing wind turbine blade structure

Info

Publication number: CN114278494A
Application number: CN202111448445.2A
Authority: CN
Inventors: 胡佳密; 叶学民; 李春曦; 刘成治; 苏顺龙
Original assignee: North China Electric Power University
Current assignee: North China Electric Power University
Priority date: 2021-11-25
Filing date: 2021-11-25
Publication date: 2022-04-05

Abstract

The invention discloses a whale tail fin imitated high-lift noise reduction wind turbine blade structure which comprises a basic airfoil type NACA0012 blade main body 1 and a whale tail fin imitated wing flap 4. The whale-like tail fin flaps are positioned at the tail edges of the basic airfoil blades and symmetrically distributed on two sides of the suction surface 2 and the pressure surface 3 of the blades. The overall height of the tail fin flap of the whale is 3.57 percent of the local chord length of the blade, and the unfolding angle of the tail fin flap is 116 degrees. The invention can realize effective control of flow separation, can obviously reduce pressure pulsation at the tail edge of the blade, improve the flow structure of the wake flow of the blade, improve the lift coefficient of the blade, reduce the resistance coefficient and effectively reduce aerodynamic noise.

Description

Whale tail fin-imitated lift-increasing noise-reducing wind turbine blade structure

Technical Field

The invention relates to the technical field of wind power generation, in particular to a bionic trailing edge wind power generator blade structure modification design.

Background

In 2020, the proposal of the double carbon target of '30 and 60' puts forward new requirements on the power industry, requires the vigorous development of renewable energy sources, and comprehensively promotes the development and high-quality development of wind power and solar power generation. Wind energy is a clean renewable energy source, the most main form of wind energy utilization is wind power generation at present, and the development of wind power generation has very important significance for adjusting energy structure, lightening environmental pollution, solving energy crisis and realizing 2030 'carbon peak reaching'. In addition, wind turbines generate significant noise during operation, which has a significant impact on the physical and mental health of nearby residents and on the migration of birds.

The wind turbine airfoil profile is the key for ensuring good dynamic performance of the wind turbine, the excellent wind turbine airfoil profile can effectively improve the aerodynamic performance of the blade and improve the energy obtaining efficiency of the wind turbine, so that the wind energy utilization rate is improved, the type and parameters of the wind turbine are reasonably selected, the wind turbine airfoil profile structure is optimized, and the wind turbine airfoil profile has positive effects of increasing the airfoil profile lift coefficient, reducing the resistance coefficient, controlling flow separation and reducing noise. Therefore, the design of the novel blade with the functions of increasing lift, reducing drag and reducing noise has important practical application value.

Disclosure of Invention

Based on the analysis and the actual demand, the application aims to provide a whale tail fin-imitated wind turbine blade with the functions of increasing lift and reducing noise, the whale tail fin-imitated wind turbine blade structure with the functions of increasing lift and reducing noise can effectively control flow separation of a boundary layer, improve a vortex structure of a wake area of the blade and weaken noise of a trailing edge of a turbulent flow boundary layer generated when the turbulent flow boundary layer flows over the trailing edge of the blade, so that the flap structure of the tail fin can improve lift-drag ratio of the blade, improve aerodynamic performance of the blade and effectively reduce noise.

The purpose of the application is mainly realized by the following technical scheme:

the application provides a high lift wind turbine blade structure of making an uproar falls in imitative whale tail fin, bionical blade structure include basic airfoil blade main part, its characterized in that basic airfoil blade main part trailing edge department is provided with whale tail fin wing flap structure.

Further, whale tail fin-shaped flaps are arranged at the tail edges of the basic wing-shaped blades, and the positions of the flaps can be adjusted according to the positions of the separation points.

Furthermore, whale tail fin flaps are symmetrically distributed on two sides of the suction surface and the pressure surface of the blade.

Further, the overall height H of the whale tail fin flap is 3.57% of the local chord length.

Further, the whale tail fin flap unfolding angle theta is 116 degrees.

Further, the contour line of a typical whale tail fin is obtained through image processing of the whale tail fin flap, specific structural contour parameters are shown in table 1, and scaling is performed according to the proportion, so that a tail fin-shaped flap structure based on bionics is obtained. The whale tail fin-shaped flap can effectively improve the tail vortex flow which originally slides down from the suction surface and the pressure surface and is converged at the tail edge to interact, thereby weakening the aerodynamic noise of the tail edge area, and simultaneously, the whale tail fin-flap structure improves the lift-drag ratio of the blade.

Compared with the prior art, the application can realize the following beneficial effects:

(a) the flow separation on the surface of the wing profile is effectively controlled through the whale-shaped flap, the aerodynamic characteristics of the wing profile are improved, and the lift-drag ratio of the wing profile is improved;

(b) the interaction of trailing edge vortexes of the suction surface and the pressure surface is controlled, so that the vortex structure of the trailing edge area of the blade is improved, and aerodynamic noise is reduced;

(c) simple structure, low manufacturing cost and strong practicability.

Drawings

FIG. 1 is a two-dimensional schematic view of a whale tail fin imitated wind turbine blade structure for increasing lift and reducing noise;

FIG. 2 is a schematic view of an embodiment of a whale tail fin flap in the whale tail fin imitated wind turbine blade structure for increasing lift and reducing noise;

FIG. 3 is a schematic diagram of the structure of the tail fin of the whale of the present invention.

Reference numerals:

1-a base airfoil blade body; 2-suction surface of the blade; 3-blade pressure surface; 4-whale tail fin lift-increasing noise-reducing and noise-reducing component structure; h-the overall height of the whale tail fin flap is mm; theta-whale tail fin spread angle, degree.

Detailed Description

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

The invention designs a high-lift noise-reducing and noise-reducing blade structure as shown in fig. 1 and 2, the main body of the high-lift noise-reducing wind turbine blade structure is a basic airfoil NACA0012 blade, whale tail fin-shaped flaps are arranged at the tail edge of the airfoil, and the whale tail fin-shaped flaps are arranged at the tail edge of the basic airfoil and symmetrically distributed on two sides of a pressure surface and a suction surface of the blade. The shape of the whale tail fin flap obtains the external outline of the tail fin through image processing of a whale tail fin picture. The overall height of the flap is 3.57 percent of the local chord length. The flap spread angle theta is 116 degrees, namely the included angle between the single-side flap and the chord line of the airfoil is 58 degrees. The whale tail fin structure and the base wing profile are not on the same horizontal plane and are determined by local incoming flow characteristics.

The above-mentioned embodiments are merely preferred embodiments of the present invention, and the scope of the present invention is not limited thereto, so that variations based on the shape and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A high-lift noise-reduction wind turbine blade structure imitating a whale tail fin mainly comprises a basic airfoil blade main body (1) and a whale tail fin flap (4). The bionic tail fin wing flaps are characterized in that bionic tail fin wing flaps (4) which are scaled in proportion according to whale tail fin prototypes are arranged at the tail edge of the basic blade main body (1), and the bionic tail fin wing flaps are symmetrically distributed on two sides of a suction surface 2 and a pressure surface 3 of the tail edge of the blade and form a certain angle with an airfoil chord line.

2. A whale tail fin imitated wind turbine blade structure with high lift and noise reduction function according to claim 1, characterized in that the overall height of a whale tail fin flap (4) is 3.57% of the local chord length of the blade.

3. The whale tail fin imitated wind turbine blade structure with the lift increasing and the noise reducing functions as claimed in claim 2, wherein the expansion angle of the whale tail fin is 116 degrees.

4. The whale tail fin imitated wind turbine blade structure with the lift and the noise reduction function is characterized in that the whale tail fin flap can effectively improve the direct interaction of vortexes with different pressures of a suction surface and a pressure surface at the tail edge to generate tail edge noise and instability of aerodynamic characteristics, so that the structure can effectively improve the aerodynamic characteristics of an airfoil profile, improve the lift-drag ratio of the airfoil profile and achieve an obvious noise reduction effect.