CN104819106A - Wind turbine blade wing section group - Google Patents
Wind turbine blade wing section group Download PDFInfo
- Publication number
- CN104819106A CN104819106A CN201510215113.8A CN201510215113A CN104819106A CN 104819106 A CN104819106 A CN 104819106A CN 201510215113 A CN201510215113 A CN 201510215113A CN 104819106 A CN104819106 A CN 104819106A
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- China
- Prior art keywords
- aerofoil profile
- wing section
- wing
- wind turbine
- turbine blade
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
- F05B2240/00—Components
- F05B2240/20—Rotors
- F05B2240/21—Rotors for wind turbines
Abstract
The invention discloses a wind turbine blade wing section group which comprises a first wing section, a second wing section and a third wing section. The outlines of the first wing section, the second wing section and the third wing section are formed by smoothly connecting non-dimensional two-dimensional coordinates, the non-dimensional two-dimensional coordinates are obtained by using horizontal coordinates and longitudinal coordinates of all points on the pressure faces and suction force faces of the first wing section, the second wing section and the third wing section to divide the chord lengths of the wing sections. The relative thicknesses of the first wing section, the second wing section and the third wing section are respectively 23%, 27% and 32%, and the maximum camber positions are respectively located at the positions of the chord lengths of 67.6%, 74.1% and 64.4% of the front edges of the wing sections. The demands for thick wing sections of large wind turbine blades applied to a low-wind-speed wind field are met, the aerodynamic characteristics of the thick wing sections are effectively improved, the maximum lift coefficient and maximum lift-drag ratio of the thick wing sections are improved, and front edge roughness sensibility of the wing sections is reduced. Compared with existing thick wing sections, the structural performance of the blades is obviously improved, and static load under the limiting condition is reduced, so that the blades are lengthened, wind diffusion area is increased, and more wind energy is captured.
Description
Technical field
The invention belongs to pneumatic equipment blades made technical field, particularly relate to a kind of wind turbine blade airfoil family.
Background technique
It is low wind speed resource-area that the current whole nation can utilize wind energy resources district over half, for the wind energy conversion system of these area designs all presents the feature that tower cylinder is high, rotor diameter is large, compared with the wind energy conversion system of the little runner diameter of equal-wattage, in structural strength, often need other design.In order to the production capacity necessary lengthened blades identical with high wind speed can be reached, need to reduce the load that blade chord length carrys out limit blade simultaneously.In order to ensure identical exerting oneself, unique approach improves wing section lift coefficient, and thus the structural behaviour of aerofoil profile and aerodynamic performance, especially maximum lift coefficient, be the key for the success or failure of low wind speed wind field vane design of wind turbines.The development and utilization of high-lift wind mill airfoil race to China's low wind speed wind field resource is extremely important.
For the wind mill airfoil at linear leaf, need large relative thickness to improve the structural rigidity of blade; Consider the environmental conditions of wind energy conversion system, the maximum lift coefficient of aerofoil profile is insensitive to front edge roughness; Simultaneously because assembling and the factor of manufacture, aerofoil profile needs certain leading-edge radius and trailing edge thickness.These restrictive conditions are all the obstacles improving aerofoil profile maximum lift coefficient.If current wind mill airfoil is for the wind energy conversion system of linear leaf, there is the shortcomings such as thick wing type is responsive to front edge roughness, stalling characteristics are not good, maximum lift coefficient is lower.
Summary of the invention
The problem to be solved in the present invention is to provide a kind of wind turbine blade airfoil family, this family of aerofoil sections improves thick wing type to factors such as front edge roughness sensitivity, stalling characteristics, maximum lift coefficients, can meet wind energy conversion system for low wind speed and wind resource to the demand of aerofoil profile.
A kind of wind turbine blade airfoil family disclosed by the invention, comprises first, second and third aerofoil profile;
First, second and third aerofoil profile described includes leading edge, trailing edge, suction surface and pressure side, and thickness, camber and chord length;
Described each profile thickness is the ultimate range between suction surface and pressure side, each aerofoil profile chord length is the distance between each aerofoil profile leading edge and trailing edge, each camber is the ultimate range that mean camber line leaves the geometry string of a musical instrument, wherein, geometry string is the line of front and rear edge, and mean camber line is the mid point line of suction surface and pressure side;
The profile of first, second and third aerofoil profile described is formed by the smooth connection of dimensionless two-dimensional coordinate, and dimensionless two-dimensional coordinate is obtained by the abscissa of each point on the pressure side of first, second and third aerofoil profile and suction surface and the y coordinate chord length divided by this aerofoil profile respectively.
As the further improvement of technique scheme, the maximum camber position of first, second and third aerofoil profile described is respectively apart from each aerofoil profile leading edge 67.6%, 74.1% and 64.4% chord length place.Because camber is rearmounted, slow down the adverse pressure gradient near leading edge, make the maximum lift coefficient of each aerofoil profile in this family of aerofoil sections comparatively condition of equivalent thickness aerofoil profile can improve 5%-10%.
Another kind as technique scheme improves, and first, second and third aerofoil profile described comprises relative thickness, and described relative thickness is the ratio of each aerofoil profile maximum ga(u)ge and chord length; The relative thickness of first, second and third aerofoil profile described is different.
As the further improvement of technique scheme, the relative thickness of first, second and third aerofoil profile described is respectively 23%, 27% and 32%.
Another kind as technique scheme improves, and the position of the maximum ga(u)ge of described each aerofoil profile is apart from each aerofoil profile leading edge 30.2%, 30.4% and 24.5% chord length place.By retraining the position of maximum ga(u)ge and maximum ga(u)ge, ensure geometry and pneumatic compatibility between each aerofoil profile of family of aerofoil sections of the present invention.
Another kind as technique scheme improves, and the trailing edge thickness of described each aerofoil profile is 0.6%, 0.8% and 1.0% of chord length from the leading edge to trailing edge.
Another kind as technique scheme improves, and the pressure side rear portion of described each aerofoil profile is load mode after S type.
Most important two performance requirements of wind mill airfoil are stall performances insensitive and good to front edge roughness.Reduce the sensitivity to front edge roughness, profile of fan often needs the thickness reducing aerofoil profile upper half part compared with aviation aerofoil profile, in order to produce the lift identical with former aerofoil profile, so the rear portion of pressure side presents S type realize rear load mode.
Wind turbine blade airfoil family geometrical construction feature of the present invention meet be applied to low wind speed wind field large scale wind power machine blade to the demand of thick wing type, effectively improve the aerodynamic characteristic of thick wing type, aerofoil profile maximum lift coefficient is improve while meeting structural characteristics, maximum lift-drag ratio, reduces aerofoil profile to front edge roughness receptance.Compare with the thick wing type existed at present, under identical condition of exerting oneself, obviously can improve the structural behaviour of blade, reduce blade area thus static load under reducing limited conditions, thus wind sweeping area can be increased, more capturing wind energy by lengthened blades.
Accompanying drawing explanation
Fig. 1 is wind turbine blade airfoil family structural representation of the present invention;
Fig. 2 is the first airfoil geometry shape figure;
Fig. 3 is the second airfoil geometry shape figure;
Fig. 4 is the 3rd aerofoil profile geometrical shape figure;
When Fig. 5 is reynolds' number=6000000, the first aerofoil profile rises resistance curve figure;
The polar figure of the first aerofoil profile when Fig. 6 is reynolds' number=6000000;
When Fig. 7 is reynolds' number=6000000, the second aerofoil profile rises resistance curve figure;
The polar figure of the second aerofoil profile when Fig. 8 is reynolds' number=6000000;
When Fig. 9 is reynolds' number=6000000, the 3rd aerofoil profile rises resistance curve figure;
The polar figure of the 3rd aerofoil profile when Figure 10 is reynolds' number=6000000.
Embodiment
Below in conjunction with accompanying drawing, a kind of wind turbine blade airfoil family of the present invention is described in detail.
Design principle: most important two performance requirements of profile of fan are stall performances insensitive and good to front edge roughness.Reduce the sensitivity to front edge roughness, profile of fan often needs the thickness reducing aerofoil profile upper half part compared with aviation aerofoil profile, and in order to produce the lift identical with former aerofoil profile, the rear portion of pressure side often presents S-type and realizes rear load mode.In order to obtain the maximum lift coefficient of needs and good stall performance, bilateral constraint is carried out to the lift coefficient under the design maximum angle of attack and stall angle.In addition retrain the breakout locations of suction surface, under the design angle of attack, separation point at airfoil trailing edge, and should move to leading edge when stall.For reaching insensitive to front edge roughness, the position of pressure side turning point is retrained reaching before and after maximum lift coefficient.In order to increase ratio of lift coefficient to drag coefficient, turn that twist before stall should more downstream be better.But turning point should near leading edge constantly when reaching maximum lift coefficient.In theory, even if for the smooth situation of leading edge because the most of region of twisting suction surface that turns so early also enters turbulence state, thus ensure that the maximum lift coefficient of smooth leading edge and coarse leading edge and lift coefficient slope difference minimum.The added influence that leading edge is coarse inevitably increases profile drag coefficient.Notice that the existence cannot measured due to rough zone of this processing method causes flow through aerofoil time boundary layer displacement thickness thickening effect.Structure and pneumatic on some additional constraints and the similarity of objective function for ensureing geometry and pneumatic compatibility between each aerofoil profile of same gang.These retrain to comprise and meet the requirements of thickness to maximum relative thickness constraint.Other geometric constraints are used to retrain air foil shape, comprise the position of maximum ga(u)ge, and the song effect of aerofoil profile specific part molded line.
As shown in Figure 1, wind turbine blade airfoil family of the present invention, comprises first, second and third aerofoil profile 10,11,12;
As described in Fig. 2,3 and 4, first, second and third aerofoil profile 10,11,12 includes leading edge 1, trailing edge 2, suction surface 3 and pressure side 4, and leading-edge radius 5, thickness, camber and chord length.As preferably, load after the pressure side rear portion of described each aerofoil profile is S type.Described each profile thickness is the distance between suction surface 3 and pressure side 4, each aerofoil profile chord length is the length of the string of a musical instrument 8 between each aerofoil profile leading edge and trailing edge, each camber is the ultimate range that mean camber line 9 leaves the geometry string of a musical instrument, wherein, geometry string is the line of front and rear edge, and mean camber line 9 is the mid point line of suction surface and pressure side.Wherein, thickness and camber have maximum ga(u)ge 6 and maximum camber 7.The profile of first, second and third aerofoil profile 10,11,12 described, respectively by the abscissa of each point on the pressure side 3 of first, second and third aerofoil profile 10,11,12 and suction surface 4 and the y coordinate chord length divided by this aerofoil profile, obtain the dimensionless two-dimensional coordinate of this aerofoil profile, formed by this dimensionless two-dimensional coordinate smooth connection.
Maximum camber 7 position of first, second and third aerofoil profile 10,11,12 described is respectively apart from each aerofoil profile leading edge 67.6%, 74.1% and 64.4% chord length place.
First, second and third aerofoil profile 10,11,12 described comprises relative thickness, and described relative thickness is the ratio of each aerofoil profile maximum ga(u)ge 6 and chord length; The relative thickness of first, second and third aerofoil profile 10,11,12 described is different: relative thickness is respectively 23%, 27% and 32%.
The position of the maximum ga(u)ge 6 of described each aerofoil profile is apart from each aerofoil profile leading edge 30.2%, 30.4% and 24.5% chord length place.
The trailing edge thickness of described each aerofoil profile is 0.6%, 0.8% and 1.0% of chord length from the leading edge to trailing edge.
For first, second and third aerofoil profile when reynolds' number (Re)=6000000.As shown in Fig. 5,7 and 9, maximum lift coefficient reaches when the angle of attack is 16 degree, and maximum lift coefficient is 1.99.In range of angles of attack is from-2 ° to 14 °, lift coefficient has well pioneer with angle of attack variation.After having crossed maximum lift coefficient, this thickness aerofoil profile has good stall performance, and the decline of lift coefficient is relatively mild with angle of attack increase.As shown in Fig. 6,8 and 10, lift coefficient does not have violent change reaching resistance coefficient before 1.9, and aerofoil profile is therefore close to there being large ratio of lift coefficient to drag coefficient during maximum lift coefficient.
By CFD(computation fluid dynamics) simulation, family of aerofoil sections disclosed in this invention three aerofoil profiles at Re=6,000, when 000, the maximum lift coefficient under turbulent-flow conditions is respectively 1.95,1.83 and 1.43.More than 5% is improved compared with the wing section lift coefficient of existing level.Exert oneself on an equal basis and can reduce vane airfoil profile chord length 5%, blade can be increased by 5% by equal static load, thus wind sweeping area increases by 10%, can catch the power of 10% more.
Embody rule approach of the present invention is a lot, and the above is only the preferred embodiment of the present invention, should be understood that; for those skilled in the art; under the premise without departing from the principles of the invention, can also make some improvement, these improvement also should be considered as protection scope of the present invention.
Claims (7)
1. a wind turbine blade airfoil family, is characterized in that, comprises first, second and third aerofoil profile;
First, second and third aerofoil profile described includes leading edge, trailing edge, suction surface and pressure side, and thickness, camber and chord length;
Described each profile thickness is the ultimate range between suction surface and pressure side, each aerofoil profile chord length is the distance between each aerofoil profile leading edge and trailing edge, each camber is the ultimate range that mean camber line leaves the geometry string of a musical instrument, wherein, geometry string is the line of front and rear edge, and mean camber line is the mid point line of suction surface and pressure side;
The profile of first, second and third aerofoil profile described is formed by the smooth connection of dimensionless two-dimensional coordinate, and dimensionless two-dimensional coordinate is obtained by the abscissa of each point on the pressure side of first, second and third aerofoil profile and suction surface and the y coordinate chord length divided by this aerofoil profile respectively.
2. wind turbine blade airfoil family according to claim 1, is characterized in that, the maximum camber position of first, second and third aerofoil profile described is respectively apart from each aerofoil profile leading edge 67.6%, 74.1% and 64.4% chord length place.
3. wind turbine blade airfoil family according to claim 1, is characterized in that, first, second and third aerofoil profile described comprises relative thickness, and described relative thickness is the ratio of each aerofoil profile maximum ga(u)ge and chord length; The relative thickness of first, second and third aerofoil profile described is different.
4. wind turbine blade airfoil family according to claim 3, is characterized in that, the relative thickness of first, second and third aerofoil profile described is respectively 23%, 27% and 32%.
5. wind turbine blade airfoil family according to claim 1, is characterized in that, the position of the maximum ga(u)ge of described each aerofoil profile is apart from each aerofoil profile leading edge 30.2%, 30.4% and 24.5% chord length place.
6. wind turbine blade airfoil family according to claim 1, is characterized in that, the trailing edge thickness of described each aerofoil profile is chord length 0.6%, 0.8% and 1.0% from the leading edge to trailing edge.
7. wind turbine blade airfoil family according to claim 1, is characterized in that, the pressure side rear portion of described each aerofoil profile is load mode after S type.
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| CN201510215113.8A CN104819106A (en) | 2015-04-30 | 2015-04-30 | Wind turbine blade wing section group |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106553749A (en) * | 2015-09-25 | 2017-04-05 | 波音公司 | For the Low Speed Airfoil design of the pneumatic improvement performance of UAV |
| CN105863954B (en) * | 2016-03-25 | 2018-06-15 | 天津工业大学 | A kind of blunt trailing edge design method of wind mill airfoil based on geometric transformation |
| CN110435873A (en) * | 2019-08-15 | 2019-11-12 | 西北工业大学 | A kind of half blended wing-body anury formula Unmanned Aerial Vehicle Airfoil race cruised from trim |
| CN110985285A (en) * | 2019-11-21 | 2020-04-10 | 广东海洋大学 | Vertical axis wind turbine blade, vertical axis wind wheel and vertical axis wind turbine |
| CN112065651A (en) * | 2020-07-21 | 2020-12-11 | 兰州理工大学 | Airfoil for wind turbine blade layer of wind generating set |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106553749A (en) * | 2015-09-25 | 2017-04-05 | 波音公司 | For the Low Speed Airfoil design of the pneumatic improvement performance of UAV |
| CN105863954B (en) * | 2016-03-25 | 2018-06-15 | 天津工业大学 | A kind of blunt trailing edge design method of wind mill airfoil based on geometric transformation |
| CN110435873A (en) * | 2019-08-15 | 2019-11-12 | 西北工业大学 | A kind of half blended wing-body anury formula Unmanned Aerial Vehicle Airfoil race cruised from trim |
| CN110435873B (en) * | 2019-08-15 | 2021-04-23 | 西北工业大学 | Cruise self-balancing semi-wing body fusion tailless unmanned aerial vehicle wing type family |
| CN110985285A (en) * | 2019-11-21 | 2020-04-10 | 广东海洋大学 | Vertical axis wind turbine blade, vertical axis wind wheel and vertical axis wind turbine |
| CN112065651A (en) * | 2020-07-21 | 2020-12-11 | 兰州理工大学 | Airfoil for wind turbine blade layer of wind generating set |
| CN112065651B (en) * | 2020-07-21 | 2021-12-14 | 兰州理工大学 | Airfoil for wind turbine blade layer of wind generating set |
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