Numerical simulation method of influence of PTFE-based membrane on aerodynamic characteristic of wind turbine blade

Patent metadata

Field	Value
Publication number	US-12406115-B2
Application number	US-202017640738-A
Country	US
Kind code	B2
Filing date	Dec 15, 2020
Priority date	Nov 5, 2020
Publication date	Sep 2, 2025
Grant date	Sep 2, 2025

Abstract

The disclosure discloses a numerical simulation method of an influence of a polytetrafluoroethylene (PTFE)-based membrane on an aerodynamic characteristic of a wind turbine blade, and relates to the technical field of polymer composites. The simulation method comprises the following steps: selecting a wind turbine generator, a blade airfoil and a PTFE-based nano functional membrane; setting a numerical simulation computation network and a computation area of a wind energy capture area; determining main computation parameters and a Reynolds number for aerodynamic characteristic computation; establishing a geometrical model whose airfoil boundary extends by 0.26 mm (membrane thickness) along a normal direction to obtain a new computational geometry; computing by using a hydrodynamic computation method and a finite volume method; and obtaining an influence number simulation computation result.

First claim

The invention claimed is:

1. A numerical simulation method of an influence of a polytetrafluoroethylene (PTFE)-based membrane on an aerodynamic characteristic of a wind turbine blade, wherein numerical simulation computation is performed on influences of a PTFE-based nano functional composite membrane on aerodynamic characteristics and entire aerodynamic performance of a blade airfoil after pasting and covering the surfaces of blades of a large horizontal axis wind turbine by using a hydrodynamic computation method, which comprises the following steps:
(1) selecting two blade airfoils;
(2) determining that wind energy capture areas of a blade are located in middle and tip areas of the blade, selecting chord length positions and angle of attack ranges of the two airfoils according to respective spreading position and chord length distribution direction, and meanwhile selecting Reynolds numbers for aerodynamic characteristic computation of the airfoils;
(3) selecting a PTFE-based nano functional composite membrane with a maximum thickness of 0.26 mm and a surface roughness of 0.18 μm;
(4) solving a two-dimension incompressible Navier-Stokes equation by using a finite volume method, wherein the computation state is a steady state, turbulence simulation adopts an SST k-ω model, the computation grid of the airfoil adopts a C-shaped structure grid, and the height of the first-layer grid of the surface of the blade satisfies y+≈1 (the first layer is a bottom layer, and y+ represents a thickness, and 1 represents a precision);
(5) geometrically modeling, and spreading the boundary of the airfoil along a normal direction by the same distance as a membrane thickness to obtain a new computational geometry;
(6) performing influence number simulation computation, wherein the action point of a moment is selected at the position of ¼ chord length of the airfoil, so that the rise moment of the airfoil is positive, and the bow moment of the airfoil is negative,
an airfoil lift coefficient is

C
L

=

L

1
2

⁢
ρ
⁢

V
∞
2

⁢
c

;

a drag coefficient is

C
D

=

D

1
2

⁢
ρ
⁢

V
∞
2

⁢
c

;

a pitching moment coefficient is

C
M

=

M

1
2

⁢
ρ
⁢

V
∞
2

⁢

c
2

;

and
(7) comparatively analyzing changes in aerodynamic coefficients of two wind turbine generator blade airfoils before and after being pasted and covered with the PTFE-based nano functional composite membrane to obtain influence number simulation computation results.

2. The numerical simulation method of the influence of the PTFE-based membrane on an aerodynamic characteristic of a wind turbine blade according to claim 1 , comprising the following steps:
(1) selecting four wind turbine generators with different capacities and models, including a China Southern Airlines NH1500 wind turbine, an American NRE5000 offshore wind turbine, a Goldwind GW103-2500 wind turbine and a Guodian United Power UP2000-96 wind turbine, and finally selecting two basic blade airfoils by integrating design data of four wind turbine generator blades, namely, DU91-W2-250 and NACA64-418;
(2) determining that the wind energy capture areas of the blade are located in the middle and tip areas of the blade, selecting chord length positions and angle of attack ranges of the two airfoils according to respective spreading position and chord length distribution direction, wherein the chord length positions are selected by referring to 60% R and 85% R positions of blades of a UP2000-96 wind turbine, R represents the chord length of each sectional airfoil of the blade in a radial direction, respectively being 1.65 m and 1.15 m; the angle of attack ranges are both [−4, 14], and meanwhile the Reynolds number for aerodynamic characteristic computation is selected as 3.0×106;
(3) selecting the PTFE-based nano functional composite membrane with a maximum thickness of 0.26 mm and a surface roughness of 0.18 μm;
(4) solving a two-dimension incompressible Navier-Stokes equation by using a finite volume method, wherein the computation state is a steady state, turbulence simulation adopts an SST k-ω model, the computation grid of the airfoil adopts a C-shaped structure grid, 400 grid points are present around the airfoil, the height of the first-layer grid of the blade surface is 9.0×10−6 m and satisfies y+≈1, and the total number of the grids is 300 thousand;
(5) geometrically modeling, and spreading the boundary of the airfoil along a normal direction by 0.26 mm to obtain a new computational geometry;
(6) performing influence number simulation computation, wherein the action point of a moment is selected at the position of ¼ chord length of the airfoil, so that the rise moment of the airfoil is positive, and the bow moment of the airfoil is negative,
an airfoil lift coefficient is

C
L

=

L

1
2

⁢
ρ
⁢

V
∞
2

⁢
c

;

a drag coefficient

C
D

=

D

1
2

⁢
ρ
⁢

V

Assignees

• China Three Gorges Corp
• China Three Gorges Renewables Group Co Ltd
• Nanjing Haohui Hi Tech Co Ltd

Inventors

• Liu Jianping
• Xiang Xin
• Wu Jianhua
• Sun Zhiyu
• Zhu Yawei
• Li Wenwei
• Li Yajing
• Wu Hong
• Zhao Jingxin
• Wu Jianping
• Min Hongwei

Classifications

• G06F30/17 Primary

  Mechanical parametric or variational design · CPC title

• G06F2111/10

  Numerical modelling · CPC title

• G06F2113/06

  Wind turbines or wind farms · CPC title

• G01M9/08 Primary

  Aerodynamic models · CPC title

• F03D1/0675

  of the blades · CPC title