CN111810353A - Forward-bent and backward-raised chord blade - Google Patents
Forward-bent and backward-raised chord blade Download PDFInfo
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- CN111810353A CN111810353A CN202010500852.2A CN202010500852A CN111810353A CN 111810353 A CN111810353 A CN 111810353A CN 202010500852 A CN202010500852 A CN 202010500852A CN 111810353 A CN111810353 A CN 111810353A
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- 238000005452 bending Methods 0.000 claims abstract description 28
- 238000013461 design Methods 0.000 claims abstract description 13
- 238000011161 development Methods 0.000 claims abstract description 4
- 238000009499 grossing Methods 0.000 claims abstract description 4
- 238000000034 method Methods 0.000 claims description 5
- 238000012360 testing method Methods 0.000 abstract description 7
- 238000005259 measurement Methods 0.000 abstract description 2
- 230000008901 benefit Effects 0.000 description 3
- 239000012530 fluid Substances 0.000 description 2
- 239000000295 fuel oil Substances 0.000 description 2
- 238000010248 power generation Methods 0.000 description 2
- 238000012827 research and development Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000011664 nicotinic acid Substances 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D1/00—Wind motors with rotation axis substantially parallel to the air flow entering the rotor
- F03D1/06—Rotors
- F03D1/065—Rotors characterised by their construction elements
- F03D1/0675—Rotors characterised by their construction elements of the blades
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63H—MARINE PROPULSION OR STEERING
- B63H1/00—Propulsive elements directly acting on water
- B63H1/02—Propulsive elements directly acting on water of rotary type
- B63H1/12—Propulsive elements directly acting on water of rotary type with rotation axis substantially in propulsive direction
- B63H1/14—Propellers
- B63H1/26—Blades
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/32—Rotors
- B64C27/46—Blades
- B64C27/473—Constructional features
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C3/00—Wings
- B64C3/10—Shape of wings
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D1/00—Wind motors with rotation axis substantially parallel to the air flow entering the rotor
- F03D1/06—Rotors
- F03D1/0608—Rotors characterised by their aerodynamic shape
- F03D1/0633—Rotors characterised by their aerodynamic shape of the blades
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/72—Wind turbines with rotation axis in wind direction
Abstract
The invention discloses a front-bent and rear-raised wing chord blade, which belongs to the field of mechanical design hydromechanics and is specifically designed as follows: firstly, selecting a world advanced conventional propeller as a foundation; airfoil locations with radii R at 0.2R, 0.25R, 0.3R to 1.0R are plotted, respectively. And then optimizing the range of forward camber and backward camber, and selecting the wing profile with the front edge less than 0.5R to the wing root with the chord forward camber and the wing profile with the rear edge less than 0.7R to the wing root with the chord backward camber. Meanwhile, optimizing the forward-bending and backward-warping parameters of the relevant chord: including the forward/aft fin chord length; a forward bow/backward rake angle; radius of curvature of the front curve/back curve; making a forward bending/backward warping data change table of each parameter along with airfoil chords with different radiuses; drawing a related airfoil chord development drawing according to a data table; carrying out smoothing treatment on each wing section; carrying out model efficacy parameter testing; and finally, carrying out full-size performance actual measurement. The invention can increase the thrust of ship propeller, the tension of unmanned plane propeller, the lift force of low-speed plane (M <0.5) wing, and the wind wheel rotation power of wind driven generator > 5%.
Description
Technical Field
The invention belongs to the fields of improving the thrust (output power) of a ship propeller, the tension of an unmanned aerial vehicle propeller, the output power of a wind wheel of a wind driven generator and the lift force of a low-speed airplane wing, and belongs to the field of mechanical design hydromechanics, in particular to a forward-bent and backward-warped chord blade.
Background
Due to the fact that the world economy is accelerated in an integrated mode, the trade quantity is increased greatly, the tonnage and the size of the steamship are increased continuously, and the fuel consumption is increased continuously. For example, a 30-ten-thousand-ton large ship needs 6000 tons of fuel oil under normal conditions, and for example, the efficiency of the propeller is improved by 5 percent, 300 tons of fuel oil can be saved, and the economic benefit is considerable. The inventor researches the propeller for a long time, and finds that the propeller can be improved by bending the blade close to the wing chord of the root airfoil forward and warping the blade backward, so that the oil quantity of the steamship is saved.
See reference (1), entitled "aircraft Engine principles course" of military and military commanders released by Chinese people in 1973 edition first and fourth minute booklets.
(2) The invention discloses a Heliwu patent number ZL201210088957.7, which discloses a wind power generation self-adaptive fan blade.
The invention provides an invention patent of a high-efficiency forward-bent and backward-raised chord blade based on the prior literature.
Disclosure of Invention
In view of the low power efficiency of the current ship propeller, the efficiency is only about 70%. The invention provides a design scheme for forward bending and backward warping of an airfoil chord at the root of a blade aiming at the problems of larger flow resistance, larger fluid attack angle and lower efficacy of the blade at the root of a propeller. The thrust and the output power of the blades are improved; the rotating power of the impeller is reduced, and the power efficiency is improved.
The blade body design of the front-bent rear raised chord blade is as follows:
step one, respectively drawing airfoil positions with the radiuses of 0.2R, 0.25R, 0.3R to 1.0R on the existing advanced conventional propeller blades.
And step two, selecting the wing profile with the front edge smaller than 0.5R to the wing root with the chord forward-curved, and the wing profile with the rear edge smaller than 0.7R to the wing root with the chord backward-warped.
And step three, determining the forward bending parameter of the leading edge (leading edge) and the backward warping parameter of the trailing edge (trailing edge) of the wing chord of each section.
The forward bending parameters include: forward curved chord length L1(ii) a Forward bend angle alpha1And radius of curvature of the front curve
Back warpThe parameters include: length L of rear fin chord2(ii) a Back rake angle alpha2And radius of curvature
Step four, respectively designing the front bending angle alpha1Length L of forward curved chord1And radius of curvature R1Forward curve data as a function of radii 0.2R, 0.25R, 0.3R, 0.4R, and 0.5R; similarly, the length L of the chord of the backward raised wing is designed2Angle of backlash alpha2And radius of curvature R2Backsweep data as a function of radii of 0.2R, 0.25R, 0.3R, 0.4R, 0.5R, 0.6R, and 0.7R.
For each airfoil, L1The chord length is 5-30%; alpha is alpha1Radius of curvature R smaller than angle of attack1Calculated according to the formula.
For each airfoil, L2The chord length is 5-25%; alpha is alpha2The value is equivalent to the attack angle, and the curvature radius R2Calculated by a formula.
And step five, respectively drawing a forward-camber backward-camber development drawing according to each airfoil chord data change table.
The specific design method of the front-bending and back-warping graph is as follows:
front curve drawing: finding a length equal to L starting from the chord front end (leading edge)1Point A of (a); making a vertical line towards the incident flow surface at the point A; finding a length equal to R on the vertical line starting from point A1A point of (a); using the point as the center of circle and R as the center of circle1The arc (circle) is drawn from the tangent line of the wing string along the direction of the front end of the wing string in radius, and the arc rotates by an angle alpha1(corresponding arc length L)1)。
Back tilted view: finding a length equal to L starting at the trailing end (trailing edge) of the chord2Point B of (a), a perpendicular line is drawn to the back flow surface at point B. Finding a length equal to R on the vertical line starting from point B2Point (2) of (c). Using the point as the center of circle and R as the center of circle2Drawing a tangent arc (circle) with the wing string from the radius to the tail end of the wing string, wherein the arc corner is alpha2(arc length L2)。
And making other corresponding chord forward-bending backward-warping drawings in the same way.
And step six, performing corresponding smoothing treatment on the profile contour change caused by forward bending and backward warping of the chord.
Compared with the prior art of advanced conventional propellers in the world, the propeller has the following advantages:
(1) the forward-bent and backward-raised chord blade can increase thrust of a ship propeller, tension of an unmanned aerial vehicle propeller, lift force of a low-speed airplane wing (M <0.5) and wind wheel rotation torque of a wind driven generator by more than 5%.
(2) The forward-bent and backward-raised chord blade can improve the output power of a ship propeller and a wind wheel of a wind driven generator by more than 5%.
(3) The forward-bent and backward-raised chord blade can improve the driving power efficiency of the ship propeller by more than 5%.
Drawings
FIG. 1 is a flow chart of the design of a forward curved aft cambered chord blade of the present invention;
FIG. 2 is a general schematic view of a large marine propeller blade of the present invention with the chord thereof curved forward and tilted backward;
FIG. 3 is a schematic view of a 0.25R airfoil chord forward camber and backward camber for a large marine propeller blade of the present invention.
Detailed Description
To facilitate an understanding and practice of the present invention for those of ordinary skill in the art, the present invention is described in further detail and in detail below with reference to marine propellers and accompanying drawings.
The front-bent and rear-raised chord blade is shown in figure 1, and firstly, a world advanced conventional propeller is selected as a performance design basis; then, parameters such as the diameter of the blade, the rotating speed, the chord length of the related airfoil, the attack angle of the fluid and the like are known; optimizing the range of forward bending and backward warping, optimizing the parameters of forward bending and backward warping of the related chord, drawing a related wing chord research and development graph according to the parameters, and performing model test on efficacy parameters, object research and development and actual efficacy measurement. The specific design is as follows:
step one, selecting a world conventional marine advanced propeller, and marking the radius R of one blade of the marine advanced propeller: the airfoil chord positions of 0.2R, 0.25R, 0.3R, 0.4R to 1.0R, and the length values of the chords and the attack angle of the flow speed are checked.
0.2R, 0.25R, 0.3R, 0.4R to 1.0R airfoil chord, as shown in FIG. 2.
Step two, preferably, the chord from the wing profile with the front edge smaller than 0.5R to the wing root is a forward bending section; the wing chord from the wing profile with the trailing edge less than 0.7R to the wing root is a backward warping section.
And step three, determining the forward bending parameter of the leading edge (leading edge) and the backward warping parameter of the trailing edge (trailing edge) of the wing chord of each section.
The forward bending parameters include: forward curved chord length L1Angle of forward bend alpha1And radius of curvature
The backward warping parameters include: length L of rear fin chord2Angle of backlash alpha2And radius of curvature
Step four, respectively designing the front bending angle alpha1Length of front camber chord L1And radius of curvature R1Forward curve data as a function of radii 0.2R, 0.25R, 0.3R, 0.4R, and 0.5R; similarly, the length L of the chord of the backward raised wing is designed2Angle of backlash alpha2And radius of curvature R2Backsweep data as a function of radii of 0.2R, 0.25R, 0.3R, 0.4R, 0.5R, 0.6R, and 0.7R.
For each airfoil, L1The chord length is 5-30%; alpha is alpha1The value is less than the angle of attack. Radius of curvature R1Is obtained according to the formula
For each airfoil, L2The value is 5-25% chord length; alpha is alpha2The value is equivalent to the angle of attack. Radius of curvature R2Calculated by a formula.
And step five, respectively designing a design drawing of the front bending and the back bending of the surface of the airfoil profile according to the data change table.
The specific design method is as follows:
as shown in FIG. 3, taking an airfoil with a radius of 0.25R as an example, the dashed line is the contour line of the forward-curved chord backward-warping front airfoil section; the full solid line is the profile line of the wing with the chord forward-bent and backward-warped.
Selecting a set of data of 0.25R chord from the forward camber data table, and finding a chord length equal to L from the front end of the chord1The point A is perpendicular to the upstream surface at the point A; finding a length equal to R on the vertical line starting from point A1A point of (a); using the point as the center of circle and R as the center of circle1Drawing a tangent arc with the wing chord from the radius to the front end of the wing chord, and rotating by an angle alpha1At 11.8 deg. the arc length is L1。
Similarly, forward bending data corresponding to the chord of 0.3R and the forward bending angle alpha are continuously selected1And forward curved chord length L1And a radius R1. And by analogy, the forward camber graph of the chord blade at each radius chord is finally obtained.
As shown in FIG. 3, a set of data of 0.25R chord is selected from the warped data table, and a length equal to L is found starting at the trailing end of the chord2Point B, where the perpendicular line is drawn to the back flow surface; finding a length equal to R on the vertical line starting from point B2A point of (a); using the point as the center of circle and R as the center of circle2The radius is drawn towards the tail end of the wing chord by drawing a tangent arc with the wing chord2At 17.8 deg. the arc length is L2。
Similarly, the back warp data corresponding to the chord of 0.3R is continuously selected to obtain the back warp angle alpha2And a length L of a rear fin chord2And radius R2. And by analogy, the backward warping drawing of the chord blade at each radius is finally obtained.
The invention is a brand new design for increasing the efficiency of the wing chord of the blade by bending forward and warping backward on the basis of the most advanced conventional propeller (for ships and unmanned aerial vehicles) and the wind wheel of the wind driven generator. For safety, model tests should be performed first. Carrying out a paddle mold water-shielding test on the marine propeller; carrying out a test flight test on the propeller of the unmanned aerial vehicle; preferably, the blades of the wind driven generator are firstly tested on a small fan; firstly, carrying out a wind tunnel blowing test on the aircraft wing; and then full-scale development is carried out.
The invention is characterized in that the leading edge (leading edge) of the chord close to the root of the blade is forward-curved towards the flow surface, and the trailing edge (trailing edge) of the airfoil is backward-curved towards the back flow surface. By the aid of the method, flow is increased, pushing force (pulling force) is increased, output power is increased, input rotation power is reduced, the pushing force and the pulling force can be improved by more than 5%, and power efficiency is improved by more than 5%.
Step six, performing corresponding smoothing treatment on profile changes of the airfoil profile caused by forward bending and backward warping of the chord; the front bent and back bent wing shapes should be smoothly processed.
Other description of the invention
a. The forward-bent and backward-raised chord blade has the advantages that the rigidity of the blade is enhanced, and the service life of the blade is prolonged; cavitation of the marine propeller is reduced; the reliability is increased; is beneficial to the backing of the steamship.
b. The application of a bionic self-adaptive fan blade (ZL 201210088957.7) for wind power generation with higher efficiency can be promoted.
c. The applicable materials are unchanged; the processing equipment can be unchanged; the cost is basically unchanged, and the efficacy is increased.
Claims (2)
1. The utility model provides a seesaw chord blade behind forward bend which designs characterized in that:
step one, respectively drawing airfoil positions with radiuses R of 0.2R, 0.25R, 0.3R to 1.0R on the conventional advanced propeller blade;
selecting the wing profile with the front edge smaller than 0.5R to the wing root to have a chord forward bend, and the wing profile with the rear edge smaller than 0.7R to have a chord backward warp;
determining the forward bending parameter of the leading edge (leading edge) and the backward warping parameter of the trailing edge (trailing edge) of each section airfoil chord;
the forward bending parameters include: forward curved chord length L1(ii) a Forward bend angle alpha1And radius of curvature of the front curve
The backward warping parameters include: length L of rear fin chord2(ii) a Back rake angle alpha2And radius of curvature
Step four, respectively designing the front bending angle alpha1Long front camber chordDegree L1And radius of curvature R1Forward curve data as a function of radii 0.2R, 0.25R, 0.3R, 0.4R, and 0.5R; similarly, the length L of the chord of the backward raised wing is designed2Angle of backlash alpha2And radius of curvature R2Back warp data table with radii of 0.2R, 0.25R, 0.3R, 0.4R, 0.5R, 0.6R and 0.7R;
step five, respectively drawing a forward-camber backward-camber development drawing according to each airfoil chord data change table;
the specific design method of the front-bending and back-warping graph is as follows:
front curve drawing: finding a length equal to L starting from the chord front end (leading edge)1Point A of (a); making a vertical line towards the incident flow surface at the point A; finding a length equal to R on the vertical line starting from point A1A point of (a); using the point as the center of circle and R as the center of circle1The arc (circle) is drawn from the tangent line of the wing string along the direction of the front end of the wing string in radius, and the arc rotates by an angle alpha1(corresponding arc length L)1)；
Back tilted view: finding a length equal to L starting at the trailing end (trailing edge) of the chord2Point B, where the perpendicular line is drawn to the back flow surface; finding a length equal to R on the vertical line starting from point B2A point of (a); using the point as the center of circle and R as the center of circle2Drawing a tangent arc (circle) with the wing string from the radius to the tail end of the wing string, wherein the arc corner is alpha2(arc length L2)；
Making other corresponding chord front-bending back-warping drawings by the same method;
and step six, performing corresponding smoothing treatment on the profile contour change caused by forward bending and backward warping of the chord.
2. The forward curved aft chord blade of claim 1 wherein in step four, L is the pitch for each airfoil1The chord length is 5-30%; alpha is alpha1Radius of curvature R smaller than angle of attack1Calculating according to the formula;
for each airfoil, L2The chord length is 5-25%; alpha is alpha2The value is equivalent to the attack angle, and the curvature radius R2Calculated by a formula.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010500852.2A CN111810353B (en) | 2020-06-04 | 2020-06-04 | Forward-bent and backward-raised chord blade |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010500852.2A CN111810353B (en) | 2020-06-04 | 2020-06-04 | Forward-bent and backward-raised chord blade |
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| Publication Number | Publication Date |
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| CN111810353A true CN111810353A (en) | 2020-10-23 |
| CN111810353B CN111810353B (en) | 2023-01-17 |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19963086C1 (en) * | 1999-12-24 | 2001-06-28 | Aloys Wobben | Rotor blade for wind-turbine energy plant divided into 2 sections with different blade tip to wind velocity ratios |
| CN101498275A (en) * | 2008-01-30 | 2009-08-05 | 内蒙古工业大学 | Horizontal axle wind mill with S blade tip winglet |
| CN102062044A (en) * | 2010-12-23 | 2011-05-18 | 中国科学院工程热物理研究所 | Wind machine blade airfoil family |
| CN102444540A (en) * | 2011-11-10 | 2012-05-09 | 深圳市艾飞盛风能科技有限公司 | Wind turbine blade aerofoil of horizontal axis wind turbine |
| CN114201841A (en) * | 2020-09-02 | 2022-03-18 | 江苏金风科技有限公司 | Blade design method and blade for wind generating set |
-
2020
- 2020-06-04 CN CN202010500852.2A patent/CN111810353B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19963086C1 (en) * | 1999-12-24 | 2001-06-28 | Aloys Wobben | Rotor blade for wind-turbine energy plant divided into 2 sections with different blade tip to wind velocity ratios |
| CN101498275A (en) * | 2008-01-30 | 2009-08-05 | 内蒙古工业大学 | Horizontal axle wind mill with S blade tip winglet |
| CN102062044A (en) * | 2010-12-23 | 2011-05-18 | 中国科学院工程热物理研究所 | Wind machine blade airfoil family |
| CN102444540A (en) * | 2011-11-10 | 2012-05-09 | 深圳市艾飞盛风能科技有限公司 | Wind turbine blade aerofoil of horizontal axis wind turbine |
| CN114201841A (en) * | 2020-09-02 | 2022-03-18 | 江苏金风科技有限公司 | Blade design method and blade for wind generating set |
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| CN111810353B (en) | 2023-01-17 |
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