WO2018135093A1

WO2018135093A1 - Rotor

Info

Publication number: WO2018135093A1
Application number: PCT/JP2017/039988
Authority: WO
Inventors: 劉　浩; 武夫藤井; 康太小久保
Original assignee: テラル株式会社
Priority date: 2017-01-18
Filing date: 2017-11-06
Publication date: 2018-07-26
Also published as: JP6709741B2; JP2018115607A

Abstract

This rotor 1 for pneumatic and hydraulic machinery has a main body blade part 50 and a blade-end trailing edge blade part 40. Between the main body blade part and the blade-end trailing edge blade part, a blade-length-directional slit 31 and a blade-chord-directional slit 32 are divided, and a leading edge 43 of the blade-end trailing edge blade part is positioned nearer to the front-surface side or rear-surface side of the rotor than is an airfoil center axis CAL53 of a virtual blade-end blade part 53.

Description

Rotor

The present invention relates to a rotor used in a wind hydraulic machine such as a wind power generator or a blower.

Conventionally, in order to improve the efficiency of wind-powered machines such as wind power generators and blowers, various efforts have been made with respect to the blade structure of rotors for wind-powered machines (for example, Patent Document 1).

JP 2003-336572 A

However, the conventional rotor still has room for improving the efficiency of the wind hydraulic machine.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a rotor that can improve the efficiency of a wind hydraulic machine.

The gist configuration of the present invention for achieving the above object is as follows.

The rotor of the present invention is
A hub supported by the main shaft;
A wing connected to the hub;
A rotor for a wind and hydraulic machine,
The wing
The wings of the main body,
A wing tip trailing edge wing located on the wing tip trailing edge side with respect to the main body wing,
Have
Between the main body wing and the wing tip trailing edge wing,
A blade length direction slit extending through the blade in the blade thickness direction, extending from the blade tip toward the blade root side of the blade and terminating before reaching the blade root;
The blade penetrates the blade in the blade thickness direction, extends from the blade root side end of the blade length direction slit toward the trailing edge side of the blade and terminates before reaching the trailing edge, and has a slit width of approximately A chord slit which is zero,
Is divided,
The leading edge of the blade tip trailing edge blade portion is a virtual blade formed by smoothly extending a portion of the main body blade portion located on the leading edge side with respect to the blade tip trailing edge blade portion to the blade trailing edge. It is located on the front side or the back side of the rotor from the airfoil center line of the end wing part.
According to the rotor of the present invention, the efficiency of the wind hydraulic machine can be improved.

In the rotor of the present invention,
The blade length direction slit is preferably extended linearly with a substantially constant slit width.
Thereby, the efficiency can be further improved.

In the rotor of the present invention,
The leading edge of the blade tip trailing edge wing is located on the front side of the rotor from the airfoil center line of the virtual blade tip wing,
The airfoil center line of the virtual blade tip wing part and the airfoil center line of the blade tip trailing edge wing part are each curved so as to be convex on the back side of the rotor,
It is preferable that the angle θ formed by the smaller chord line of the virtual wing tip wing portion and the chord line of the wing tip trailing edge wing portion is 0 ° or more.
Thereby, the efficiency can be further improved.

In the rotor of the present invention,
The airfoil center line of the virtual wing tip wing part and the airfoil center line of the wing tip trailing edge wing part each extend linearly,
It is preferable that an angle θ formed by the smaller chord line of the virtual wing tip wing portion and the chord line of the wing tip trailing edge wing portion is larger than 0 °.
Thereby, the efficiency can be further improved.

In the rotor of the present invention,
The leading edge of the blade tip trailing edge wing is located on the back side of the rotor from the airfoil center line of the virtual blade tip wing,
The airfoil center line of the virtual blade tip wing part and the airfoil center line of the blade tip trailing edge wing part are each curved so as to be convex on the front side of the rotor,
It is preferable that the angle θ formed by the smaller chord line of the virtual wing tip wing portion and the chord line of the wing tip trailing edge wing portion is 0 ° or more.
Thereby, the efficiency can be further improved.

In the rotor of the present invention,
The angle θ formed by the smaller chord line of the virtual wing tip wing part and the chord line of the wing tip trailing edge wing part is preferably less than 5 °.
Thereby, the efficiency can be further improved.

In the rotor of the present invention,
It is preferable that the blade length direction slit is located on the trailing edge side of the chord centerline connecting the chord line center points of the virtual blade tip wing portion.
Thereby, the efficiency can be further improved.

In the rotor of the present invention,
It is preferable that the wing has a plurality of wing tip trailing edge wings arranged at different positions in the chord direction of the wing.
Thereby, the efficiency can be further improved.

According to the present invention, it is possible to provide a rotor that can improve the efficiency of a wind hydraulic machine.

It is a front view showing an example of a rotor concerning a 1st embodiment of the present invention. It is a perspective view which shows a mode that the rotor shown in FIG. 1 was seen from the front side. It is a side view which shows a mode that the rotor shown in FIG. 1 was seen from the blade end side. It is a front view showing the 1st modification of the rotor concerning a 1st embodiment of the present invention. It is a side view which shows a mode that the rotor shown in FIG. 4 was seen from the blade end side. It is a side view which shows a mode that the 2nd modification of the rotor which concerns on 1st Embodiment of this invention was seen from the blade end side. It is a front view which shows the 3rd modification of the rotor which concerns on 1st Embodiment of this invention. FIG. 8A is a side view showing a state where the rotor shown in FIG. 7 is viewed from the blade tip side, and FIG. 8B is a diagram for explaining the relationship between the airfoil centerlines shown in FIG. FIG. It is a side view which shows a mode that the rotor which concerns on 2nd Embodiment of this invention was seen from the blade tip side. It is a figure for demonstrating the analysis method of the rotor which concerns on a comparative example and an Example. It is a figure which shows the analysis result of the rotor which concerns on a comparative example and an Example. It is a figure which shows the analysis result of the rotor which concerns on a comparative example and an Example. It is a figure which shows the analysis result of the rotor which concerns on a comparative example and an Example. It is a figure which shows the analysis result of the rotor which concerns on an Example.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The rotor of the present invention is used for a wind hydraulic machine, and particularly suitable for use in a horizontal axis type wind power generator or blower. The “wind-hydraulic machine” as used in the present invention refers to a machine that uses power obtained by wind power or hydraulic power, such as a wind power generator (wind turbine, etc.), a blower, a hydro power generator (water turbine, etc.), a pump, a helicopter, a drone, etc. Shall mean.
The diameter of the rotor of the present invention may be any value, but is preferably 741 to 1111 mm, for example, when the rotor is used for a horizontal axis type wind power generator, and 600, for example, when the rotor is used for a blower. It is preferable that the thickness is ˜900 mm.

[First Embodiment]
A first embodiment of the present invention will be described with reference to FIGS. 1 to 3 show an example of a rotor according to the first embodiment of the present invention. 4 to 5 show a first modification of the rotor according to the present embodiment. FIG. 6 shows a second modification of the rotor according to the present embodiment.
Can be used. 7 to 8 show a third modification of the rotor according to the present embodiment.
The rotor 1 of the present embodiment is configured as a rotor for a horizontal axis type wind power generator, but is particularly suitable when configured as a rotor for a hydroelectric generator (such as a water turbine). It may be configured as a rotor for other wind hydraulic machines.

1 to 3, the rotor 1 of the present embodiment includes a hub 10 supported by a main shaft (not shown), and a plurality (three in this example) of blades 20 connected to the hub 10. ing. A main shaft (not shown) extends from the rear surface of the hub 10 toward the rear, for example, substantially horizontally, when viewed in FIG. The center axis of the main shaft is the rotation center axis O of the rotor 1.
The number of wings 20 is not limited to three and can be any number.
Moreover, although each blade 20 of the rotor 1 has the same shape as each other in this example, some blades may have a shape different from other blades.

As shown in FIGS. 2 and 3, in this example, the pitch angle (also referred to as “torsion angle”) of the blade 20 is not constant along the blade length direction of the blade 20, but the blade angle along the blade length direction. It gradually decreases from the root 21 toward the wing tip 22.
Here, the “pitch angle” is a virtual plane perpendicular to the rotation center axis O of the rotor 1 and a chord line of the blade 20 (a straight line connecting the leading edge 23 and the trailing edge 24 of the blade 20). The angle to make.
Further, the “blade length direction” refers to the center point 21 a (FIG. 1) of the chord line of the blade root 21 of the blade 20 and the blade tip of the blade 20 on the projection plane perpendicular to the rotation center axis O of the rotor 1. A direction parallel to a straight line connecting the center point 22a of the chord line 22 (FIG. 1).
The “projection plane perpendicular to the rotation center axis O of the rotor 1” corresponds to a plane when the rotor 1 is viewed from one side of the rotation center axis O as shown in FIG.
By making the distribution of the pitch angle of the blade 20 in the blade length direction as in this example, the efficiency of the wind power generator can be improved. However, the distribution of the pitch angle of the blade 20 in the blade length direction may be arbitrary.

The blade 20 of this example has a substantially rectangular shape on a projection plane perpendicular to the rotation center axis O of the rotor 1 when the pitch angle of the blade 20 is set to 0 ° over the entire length of the blade 20. It is a rectangular wing. The chord length of the wing 20 in this example (the length of a straight line connecting the leading edge 23 and the trailing edge 24 of the wing 20) is constant over the entire length of the wing 20.
However, if the pitch angle of the blade 20 is set to 0 ° over the entire length of the blade 20, the shape formed by the blade 20 on the projection plane perpendicular to the rotation center axis O of the rotor 1 may be arbitrary. In addition, the chord length of the wing 20 of the present embodiment may change at least partially along the wing length direction of the wing 20.

As shown in FIG. 1, the wing 20 includes a main wing portion 50 and a wing tip trailing edge wing portion 40 located on the wing tip trailing edge side (wing tip side and trailing edge side) with respect to the main body wing portion 50. is doing. A blade length direction slit 31 and a chord direction slit 32 are defined between the main body blade portion 50 and the blade tip trailing edge blade portion 40. The blade length direction slit 31 penetrates the blade 20 in the blade thickness direction, opens to the blade tip 22 of the blade 20, extends from the blade tip 22 toward the blade root 21, and reaches the blade root 21. It ends with. The chord direction slit 32 penetrates the wing 20 in the wing thickness direction, is connected to the end of the wing length direction slit 31 on the wing root 21 side, and extends from there to the trailing edge 24 side of the wing 20. The terminal ends before reaching the trailing edge 24. In other words, the blade tip trailing edge wing portion 40 is divided (separated) from the main body wing portion 50 by the blade length direction slit 31 and the chord direction slit 32.
In this example, the wing tip trailing edge wing portion 40 is fixed to or integrated with the main body wing portion 50 on the trailing edge 24 side of the chord direction slit 32, thereby forming the main wing portion 50 and It is connected.
In the projection plane perpendicular to the rotation center axis O of the rotor 1, the slit width of the chord direction slit 32 is substantially zero.

In this example, the blade length direction slit 31 extends in parallel to the blade length direction of the blade 20 on a projection plane perpendicular to the rotation center axis O of the rotor 1. With this configuration, the efficiency of the wind power generator can be improved. However, on the projection plane, the blade length direction slit 31 may extend in a direction intersecting the blade length direction of the blade 20.
In this example, the chord direction slit 32 extends in parallel to the chord direction of the blade 20 on the projection plane perpendicular to the rotation center axis O of the rotor 1. Here, the “chord direction” is a direction parallel to the chord line. With this configuration, the efficiency of the wind power generator can be improved. However, on the projection plane, the chord direction slit 32 may extend in a direction intersecting the chord direction of the wing 20.

As shown in FIGS. 2 and 3, the blade edge trailing edge wing portion 40 has its front edge 43 side turned toward the front side of the rotor 1 (positive pressure side in this example) with respect to the main body blade portion 50. Has a shape. More specifically, the leading edge 43 of the blade tip trailing edge blade portion 40 is located on the front side of the rotor (positive pressure side in this example) with respect to the airfoil center line CAL 53 of the virtual blade tip blade portion 53.
Here, “the leading edge 43 of the blade tip trailing edge wing portion 40” is an edge of the blade tip trailing edge wing portion 40 on the leading edge 23 side of the blade 20. Note that “the trailing edge 44 of the blade tip trailing edge wing portion 40” is an edge of the blade tip trailing edge wing portion 40 on the side of the trailing edge 24 of the blade 20, and in this example, the trailing edge 24 of the blade 20. Part of it.
Further, the “virtual blade tip wing portion 53” is a portion 51 (hereinafter referred to as a blade tip leading edge wing portion 51) located on the front edge 23 side of the blade 20 with respect to the blade tip trailing edge wing portion 40 of the main body wing portion 50. Is also a portion that is smoothly extended to the trailing edge 24 of the blade 20 (the trailing edge 44 of the blade tip trailing edge blade portion 40). In other words, the blade tip leading edge blade portion 51 and the blade tip This is a combined portion of a virtual blade end trailing edge wing 52 that smoothly extends from the trailing edge 51 a of the leading edge wing 51 to the trailing edge 24 of the wing 20. The “rear edge 51 a of the wing tip leading edge wing part 51” is an edge on the trailing edge 24 side of the wing 20 in the wing tip leading edge wing part 51.
Further, the “airfoil center line” (also referred to as “camber line”) refers to the front side of the rotor 1 (rotor front side) and the back side of the rotor 1 in the airfoil (cross section of the blade in the blade thickness direction). This is a line connecting points that are equidistant from the surface of the side (the back side of the rotor).
As shown in FIG. 3, in the present embodiment, the airfoil center line of the blade 20 is curved so as to be convex on the rotor back side. Further, the airfoil center line CAL53 of the virtual blade tip wing part 53 and the airfoil centerline CAL40 of the blade tip trailing edge wing part 40 are curved so as to be convex on the rotor back side.
By having the chord direction slit 32, as in the present example, the blade tip extends over the entire length in the blade length direction of the blade tip trailing edge wing portion 40 including the end of the blade tip trailing edge wing portion 40 on the blade root 21 side. The leading edge 43 of the end trailing edge wing 40 can be positioned on the front side of the rotor with respect to the airfoil center line CAL 53 of the virtual wing tip wing 53.
In the example shown in the figure, the airfoil shape of the main body wing part 50 and the wing tip trailing edge wing part 40 is rounded at the respective leading and trailing edges, and the main wing part 50 and the wing tip trailing edge wing. The blade thickness of the portion 40 gradually decreases from the leading edge side toward the trailing edge side along each airfoil center line, but this configuration is not essential. For example, the airfoil shape of the main body wing part 50 and the wing tip trailing edge wing part 40 may be square on at least one of the respective leading edges and trailing edges. Further, the blade thicknesses of the main body blade 50 and the blade tip trailing edge blade 40 may be substantially constant along the respective airfoil centerlines.

Hereinafter, the effect obtained by the front edge 43 of the blade tip trailing edge wing portion 40 being located on the front side of the rotor from the airfoil center line CAL 53 of the virtual blade tip wing portion 53 will be described.
If the blade 20 does not have the blade length direction slit 31 as in the case of a general blade, the rotor front surface and the rotor back surface are almost entirely extended in the blade length direction at the rear edge side portion of the blade 20. On the surface on the side, the flow of the air flow is easy to peel off, and the positive pressure and the negative pressure cannot be sufficiently generated. Therefore, sufficient lift cannot be obtained and the efficiency of the wind power generator cannot be improved.
On the other hand, in the present embodiment, the blade 20 has a blade length direction slit 31 formed in the blade 20, and the leading edge 43 of the blade tip trailing edge blade portion 40 is a rotor than the blade centerline CAL 53 of the virtual blade tip blade portion 53. Since it is located on the front side, in the blade length direction slit 31, that is, between the leading edge 43 of the blade tip trailing edge wing 40 and the trailing edge 51a of the blade tip leading edge wing 51 of the main body blade 50, A gap that allows the wind to pass through is defined. FIG. 14 shows streamlines in the vicinity of the blade tip of the blade 20 obtained by analysis using the model of the rotor 1 according to one embodiment of the present invention. Details of the analysis will be described later. As can be seen from FIG. 14, in the vicinity of the blade tip of the blade 20, the wind incident from the rotor front side and the leading edge 23 side of the blade 20 passes through the blade length direction slit 31 to the rotor rear side and the trailing edge of the blade 20. It flows to the 24 side. As a result, separation of the flow is suppressed on the surface on the rotor front side and the surface on the rotor back side in the blade tip trailing edge wing portion 40, and a large positive pressure and negative pressure can be generated respectively. That is, on the surface on the rotor front side and the surface on the rotor back side on both the leading edge side (blade tip leading edge wing portion 51) and the trailing edge side (blade tip trailing edge wing portion 40) in the vicinity of the blade tip of the blade 20, A large positive pressure and negative pressure can be generated respectively. Therefore, the lift can be improved and the efficiency of the wind power generator can be improved.
Even if there is a gap that allows the wind to pass through the blade length direction slit 31, the leading edge 43 of the blade tip trailing edge blade portion 40 is on the airfoil center line CAL 53 of the virtual blade tip blade portion 53. If it is located on the back side of the rotor than that, it becomes difficult for the wind to pass through the blade length direction slit 31, and peeling cannot be effectively suppressed.
In addition, since the pressure difference generated in the vicinity of the blade tip of the blade 20 contributes most to the generation of lift, in the present embodiment, the blade length direction slit 31 is on the blade tip side, thereby suppressing separation on the blade tip side. Since the pressure difference can be increased, the lift and thus the efficiency can be greatly improved as compared with the case where the blade length direction slit 31 is on the blade root side.

The efficiency of the wind power generator can be evaluated by the power coefficient of the wind power generator. The rotor 1 of the present embodiment has a power coefficient mainly at least one of when the peripheral speed ratio is relatively low and when it is relatively high, compared to a rotor whose blades do not have the blade length direction slit 31. Can be increased.
Here, the “circumferential speed ratio” is the ratio of the blade tip speed (speed in the rotational direction of the blade tip) to the wind speed. When the wind speed is U (m / s), the rotational speed of the rotor is ω (rpm), and the radius of the rotor is R (mm), the peripheral speed ratio λ can be expressed by the following equation (1).

The “power coefficient” is the ratio of the net output of the wind power generator to the kinetic energy of the free air flow that passes through the rotor wind receiving area per unit time. When the density of air is ρ (kg / m ³ ) and the rotational torque is T (Nm), the power coefficient C _p can be expressed by the following equation (2).

As shown in FIG. 1, in the present embodiment, the blade length direction slit 31 extends linearly with a substantially constant slit width. More specifically, on the projection plane perpendicular to the rotation center axis O of the rotor 1, the slit width d of the blade length direction slit 31 is substantially constant over the entire length of the blade length direction slit 31, and the blade length direction slit 31 extends linearly. With this configuration, it is possible to effectively suppress separation on the surface of the blade tip trailing edge wing portion 40 over the entire length in the blade length direction of the blade tip trailing edge wing portion 40, thereby improving efficiency.
However, on the projection plane, the slit width d of the blade length direction slit 31 may change at least partially along the extending direction of the blade length direction slit 31. In the projection plane, the blade length direction slit 31 may extend non-linearly.

From the viewpoint of improving efficiency, the slit width d of the blade length direction slit 31 on the projection plane perpendicular to the rotation center axis O of the rotor 1 is preferably 0 mm or more, more preferably 2 mm or more, and further preferably 5 mm or more. From the viewpoint of improving efficiency, the slit width d of the blade length direction slit 31 on the projection plane is preferably 10 mm or less.
Similarly, the slit width d of the blade length direction slit 31 on the projection plane with respect to the chord length CHL at the blade tip 22 of the blade 20 (that is, the chord length at the blade tip 22 of the virtual blade tip blade portion 53). The ratio, that is, (d / CHL) × 100 (%) is preferably 0.0% or more, more preferably 1.9% or more, and further preferably 4.8% or more. Further, (d / CHL) × 100 (%) is preferably 9.5% or less.
The first modification shown in FIGS. 4 and 5 is different from the examples shown in FIGS. 1 to 3 only in that the slit width d of the blade length direction slit 31 on the projection plane is 0 mm. As shown in FIG. 5, even when the slit width d of the blade length direction slit 31 on the projection plane is 0 mm, the leading edge 43 of the blade tip trailing edge blade portion 40 is the airfoil centerline CAL53 of the virtual blade tip blade portion 53. Since the blade is located on the front side of the rotor, the blade length direction slit 31, that is, the leading edge 43 of the blade tip trailing edge blade portion 40 and the trailing edge 51 a of the blade tip leading edge blade portion 51 of the main body blade portion 50, In between, a gap through which the wind can pass is defined. Therefore, the peeling suppression effect mentioned above is acquired.

When the blade length of the blade 20 is L, from the viewpoint of improving efficiency, the blade length direction length l of the blade length direction slit 31 on the projection plane perpendicular to the rotation center axis O of the rotor 1 is (1 / 8) L or more is preferable, (2/8) L or more is more preferable, and (3/8) L or more is more preferable. Further, from the viewpoint of improving efficiency, the blade length direction length l of the blade length direction slit 31 on the projection plane is preferably (5/8) L or less, and more preferably (4/8) L or less.
Here, the “blade length L of the blade 20” means the center point of the chord line of the blade root 21 of the blade 20 on the projection plane perpendicular to the rotation center axis O of the rotor 1, as shown in FIG. 1. The length of the straight line connecting 21a and the center point 22a of the chord line of the blade tip 22 of the blade 20 is indicated. The sum of the radius r of the hub 10 and the blade length L of the blade 20 is the radius R of the rotor 1 (R = r + L).

As in the present embodiment, the airfoil center line CAL53 of the virtual blade tip wing portion 53 and the airfoil centerline CAL40 of the blade tip trailing edge wing portion 40 are curved so as to be convex on the rotor back side. In this case, from the viewpoint of improving efficiency, the angle formed by the smaller of the chord line of the virtual wing tip wing 53 (or an extension thereof) and the chord line of the wing tip trailing edge wing 40 (or an extension thereof). θ is preferably 0 ° or more. Further, from the viewpoint of improving efficiency, an angle θ formed by a smaller one of the chord line (or an extension line thereof) of the virtual wing tip wing part 53 and the chord line (or an extension line thereof) of the wing tip trailing edge wing part 40. Is preferably less than 5 °, more preferably 3 ° or less.
In the example of FIGS. 1 to 3, the angle θ is 0 °, and the chord line of the wing tip trailing edge wing portion 40 is on the chord line of the virtual wing tip wing portion 53. On the other hand, the second modification shown in FIG. 6 differs from the examples of FIGS. 1 to 3 only in that the angle θ is larger than 0 °. As shown in FIG. 3, even when the angle θ is 0 °, the leading edge 43 of the blade tip trailing edge blade 40 is located on the rotor front side with respect to the blade centerline CAL53 of the virtual blade tip blade 53. Thus, a gap through which wind can pass through the blade length direction slit 31, that is, between the leading edge 43 of the blade tip trailing edge blade portion 40 and the trailing edge 51 a of the blade tip leading edge blade portion 51 of the main body blade portion 50. Is partitioned. Therefore, the peeling suppression effect mentioned above is acquired.

In the example of FIGS. 1 to 3, the wing 20 has only one wing tip trailing edge wing portion 40. However, as in the third modification shown in FIGS. A plurality of trailing edge wing portions 40 may be provided. In this case, each blade tip trailing edge wing portion 40 is configured such that the leading edge 43 of the blade tip trailing edge wing portion 40 is located closer to the rotor front side than the airfoil center line CAL 53 of the virtual blade tip wing portion 53. The Thereby, since the wind passes through each blade length direction slit 31 corresponding to each blade tip trailing edge wing portion 40, separation on the surface of each blade tip trailing edge wing portion 40 can be effectively suppressed. Can be improved.
7 and FIG. 8, the wing 20 has a plurality (specifically, two) wing tip trailing edge wing portions 40 arranged at different positions in the chord direction of the wing 20. This is different from the examples shown in FIGS. In the third modification, among the plurality of blade tip trailing edge wing portions 40, the blade tip trailing edge wing portion 40 closest to the leading edge 23 is between the blade length direction slit 31 and the blade chord with the main body blade portion 50. A direction slit 32 is defined. The other blade tip trailing edge wing portion 40 divides the blade length direction slit 31 between the blade tip trailing edge wing portion 40 adjacent to the leading edge side, and between the main blade portion 50 and the chord. A direction slit 32 is defined. Among the plurality of blade tip trailing edge wing portions 40, the trailing edge 44 of the blade tip trailing edge wing portion 40 closest to the trailing edge 24 forms a part of the trailing edge 24 of the blade 20. The airfoil center line CAL40 of each blade tip trailing edge wing portion 40 is curved so as to be convex on the rotor back side.
It is preferable that the slit width d of each blade length direction slit 31 and the length l in the blade length direction are within the numerical ranges described above. The slit widths d of the blade length direction slits 31 and the lengths l of the blade length direction slits 31 in the blade length direction may be the same as or different from each other as illustrated in the figure.
FIG. 8B shows only the airfoil center line CAL53 of the virtual blade tip wing portion 53 and the airfoil centerline CAL40 of each blade tip trailing edge wing portion 40 in the side view of FIG. 8A for convenience. It shows. It is preferable that the angle θ of each blade tip trailing edge wing portion 40 is within the numerical range described above. The angles θ of the blade tip trailing edge wing portions 40 may be different from each other as in the example of FIG. 8B or may be the same as each other. In the example of FIG. 8B, of the two blade tip trailing edge wing portions 40, the angle θ of the blade tip trailing edge wing portion 40 on the leading edge 23 side is the blade tip trailing edge wing portion on the trailing edge 24 side. It is smaller than the angle θ of 40.

In each of the above-described examples, the blade length direction slit 31 is located on the relatively trailing edge side of the blade 20. Rather than the trailing edge side. Thereby, since the blade length direction slit 31 is disposed in a region on the trailing edge side where peeling is particularly likely to occur, peeling on the surface of the blade tip trailing edge wing portion 40 can be more effectively suppressed.

[Second Embodiment]
A second embodiment of the present invention will be described with reference to FIG. In the rotor 1 of the second embodiment, the airfoil center line of the blade 20 extends linearly, and the airfoil center line CAL53 of the virtual blade tip wing portion 53 and the blade center of the blade tip trailing edge wing portion 40 are provided. The line CAL40 differs from the first embodiment only in that each line extends in a straight line.
The rotor 1 of the present embodiment is configured as a rotor for a horizontal axis type wind power generator, but is particularly suitable when configured as a rotor for a hydroelectric generator (such as a water turbine). It may be configured as a rotor for other wind hydraulic machines.
As shown in FIG. 9, the angle θ formed by the smaller chord line (or extension thereof) of the virtual wing tip wing portion 53 and the chord line (or extension thereof) of the wing tip trailing edge wing portion 40 is , Greater than 0 °. Accordingly, the leading edge 43 of the blade tip trailing edge blade portion 40 is positioned on the rotor front side (positive pressure side in this example) with respect to the airfoil center line CAL53 of the virtual blade tip blade portion 53. Also according to the second embodiment, when the wind passes through the blade length direction slit 31, separation on the surface of the blade tip trailing edge wing portion 40 can be effectively suppressed, and thus the efficiency can be improved.
In the second embodiment, from the viewpoint of improving efficiency, the chord line (or an extension thereof) of the virtual wing tip wing portion 64 and the chord line (or an extension thereof) of the wing tip trailing edge wing portion 40 are small. Is preferably less than 5 °, and more preferably 3 ° or less.
Other configurations are the same as those described in the first embodiment.
For example, in the second embodiment, it is preferable that the slit width d of the blade length direction slit 31 and the length l in the blade length direction are within the numerical ranges described above in the first embodiment. Also in the second embodiment, as in the example shown in FIGS. 7 and 8, the wing 20 may include a plurality of wing tip trailing edge wing portions 40.

In addition, when the rotor of each example mentioned above is comprised as a rotor for air blowers, the efficiency of an air blower can be improved. As a result, noise can be reduced.

The rotor of the present invention is not limited to the examples described above.
For example, in the first and second embodiments, the “rotor front side” and the “rotor back side” may be reversed. This configuration is particularly suitable when the rotor of the present invention is configured as a blower, pump, helicopter, or drone rotor.
More specifically, when the “rotor front side” and the “rotor back side” are reversed in the first embodiment, the blade edge trailing edge blade portion 40 has a portion on the front edge 43 side of the main blade portion. 50, the front edge 43 of the blade tip trailing edge blade portion 40 is a blade of the virtual blade tip blade portion 53. It is located on the rotor back side (positive pressure side in this example) with respect to the mold center line CAL53. The airfoil centerline of the blade 20 is curved so as to be convex on the front side of the rotor, and the airfoil centerline CAL53 of the virtual blade tip wing portion 53 and the airfoil centerline CAL40 of the blade tip trailing edge wing portion 40 are used. Are curved so as to be convex on the front side of the rotor. The angle θ formed by the smaller chord line (or extension thereof) of the virtual wing tip wing portion 53 and the chord line (or extension thereof) of the wing tip trailing edge wing portion 40 is 0 ° or more. Other configurations are the same as those described in the first embodiment.
Further, when the “rotor front side” and the “rotor rear side” are reversed in the second embodiment, the blade tip trailing edge wing portion 40 has its front edge 43 side portion with respect to the main body blade portion 50. And the leading edge 43 of the blade tip trailing edge wing portion 40 is an airfoil center line of the virtual blade tip wing portion 53. It is located on the rotor back side (positive pressure side in this example) from CAL53. The airfoil center line of the blade 20 extends linearly, and the airfoil center line CAL53 of the virtual blade tip wing portion 53 and the airfoil centerline CAL40 of the blade tip trailing edge wing portion 40 are straight lines, respectively. It extends into a shape. The angle θ formed by the smaller chord line (or extension thereof) of the virtual wing tip wing portion 53 and the chord line (or extension thereof) of the wing tip trailing edge wing portion 40 is greater than 0 °. Other configurations are the same as those described in the second embodiment.
In these cases, in the vicinity of the blade tip of the blade 20, the wind incident from the rotor back side and the leading edge 23 side of the blade 20 passes through the blade length direction slit 31 to the rotor front side and the trailing edge 24 side of the blade 20. And flow. As a result, separation of the flow is suppressed on the surface on the rotor back surface side and the surface on the rotor front side in the blade tip trailing edge wing portion 40, and a large positive pressure and negative pressure can be generated respectively. That is, on both the front edge side (blade edge leading edge wing part 51) and the trailing edge side (blade edge trailing edge wing part 40) in the vicinity of the blade tip of the blade 20, A large positive pressure and negative pressure can be generated respectively. Therefore, the lift can be improved and the efficiency of the wind hydraulic machine can be improved.
However, these configurations may be used when the rotor of the present invention is configured as a rotor for a wind power generator (wind turbine or the like) or a hydroelectric generator (water turbine or the like).

The performance of the rotors of Comparative Example 1 and Examples 1 to 10 of the present invention was evaluated by analysis and will be described. In this analysis, assuming that the rotors of the comparative examples and the examples are respectively used for wind power generators, the circumferential speed ratios λ = 0.926, 2.778, 4.630, and 6.482, respectively. The power coefficient _Cp was determined. Tip speed ratio lambda, the calculation of the power coefficient C _p, the above equation (1), was used as the (2). Then, for each value of tip speed ratio lambda, the power coefficient C _p of the examples, expressed as a percentage when the 100% power factor C _p of Comparative Example 1. The results are shown in Tables 1 to 3 and FIGS. 11 to 13 as “power coefficient ratio (%)”. 11 to 13 correspond to Tables 1 to 3, respectively.

For analysis, numerical fluid calculation software ANSYS-CFX manufactured by Ansys Corporation was used. The rotor model was subjected to steady analysis by giving a constant wind speed U = 4 m / s and a rotational speed ω. SST 乱 k -ω was used as the turbulent model. FIG. 10 shows the model 60 used for the analysis. The rotor model of each comparative example and example assumed a three-blade rotor. However, to reduce the calculation time, the calculation area was divided into three around the axis, and a periodic boundary was formed on one of the divided surfaces. Conditions were given. FIG. 14 shows streamlines in the vicinity of the blade tip of the rotor blade of the example obtained when λ = 0.926 in this analysis.

The rotors of the comparative examples and the examples are different from each other only in the shape of the blades. In each case, the rotor radius R is 463 mm, the blade length L is 349.25 mm, and the blade chord length CHL (blade The distribution of the pitch angle of the blades in the blade length direction is the same as in the examples of FIGS. 1 to 3.
The rotor blade of Comparative Example 1 was a normal rectangular blade having no blade length direction slit 31 and its airfoil center line was curved so as to be convex on the rotor back side.
The rotor blades of Examples 1 to 10 all have the structure described with reference to FIGS. 1 to 6, that is, one blade length direction slit 31 (and one blade tip trailing edge blade portion 40). The wing shape center line CAL 53 of the virtual wing tip wing portion 53 and the wing shape center line CAL 40 of the wing tip trailing edge wing portion 40 are curved so as to be convex on the rotor back side. In each of the rotor blades of the embodiments, the leading edge 43 of the blade tip trailing edge blade portion 40 is located on the front side of the rotor from the airfoil center line CAL53 of the virtual blade tip blade portion 53. Met. In the rotor blades of the respective embodiments, the leading edge side end of the blade length direction slit 31 (that is, the trailing edge 51a of the blade tip leading edge wing portion 51) is 38 in the chord length CHL from the trailing edge of the blade in the chord direction. % Distance (40 mm) apart. The rotor blades of the respective embodiments have the slit width d of the blade length direction slit 31 on the projection plane perpendicular to the rotation center axis O of the rotor 1, and the length in the blade length direction of the blade length direction slit 31 on the projection surface. The angle θ between the chord line of the virtual wing tip wing portion 53 and the chord line of the wing tip trailing edge wing portion 40 is different only by three parameter values. Details are shown in Tables 1 to 3.

Table 1 and FIG. 11 show the analysis results of Comparative Example 1 and Examples 1 to 4. In each of Examples 1 to 4, l = (2/8) L and θ = 0 °, and d was varied in the range of 0 to 8 mm.
Table 2 and FIG. 12 show the analysis results of Comparative Example 1, Examples 5, 3, and 6-8. In Examples 5, 3, and 6 to 8, d = 5 mm and θ = 0 °, and l was varied in the range of (1/8) L to (5/8) L.
Table 3 and FIG. 13 show the analysis results of Comparative Example 1, Examples 3, 9, and 10. In Examples 3, 9, and 10, d = 5 mm and l = (2/8) L, and θ was varied in the range of 0 ° to 10 °.

As can be seen from Tables 1 to 3 and FIGS. 11 to 13, the rotors of Examples 1 to 10 mainly have a relatively low peripheral speed ratio compared to the rotor of Comparative Example 1 (λ = 0.926). ) And at a relatively high time (λ = 6.482), the power coefficient C _{p and} thus the efficiency could be increased. Therefore, it was confirmed that the performance of the rotor of the present invention was improved as a whole as compared with the conventional rotor.

The rotor of the present invention is used for a wind-hydraulic machine, and particularly suitable for use in a horizontal axis type wind power generator or blower.

DESCRIPTION OF SYMBOLS 1 Rotor 10 Hub 20 Blade 21 Blade root 22 Blade tip 23 Lead edge 24 Trailing edge 31 Blade length direction slit 32 Blade chord direction slit 40 Blade tip trailing edge blade 43 Blade tip trailing edge Blade leading edge 44 Blade tip trailing edge Rear edge 50 of the wing body Main wing section 51 Front wing wing section 51a of the main wing section Trailing edge 52 of the wing edge front edge wing section Virtual wing end trailing wing section 53 of the main wing section Virtual wing tip wing section 60 Analysis Model CAL40, CAL53 Airfoil center line L Blade length O Rotor rotation center axis r Hub radius R Rotor radius RD Rotation direction

Claims

A hub supported by the main shaft;
A wing connected to the hub;
A rotor for a wind and hydraulic machine,
The wing
The wings of the main body,
A wing tip trailing edge wing located on the wing tip trailing edge side with respect to the main body wing,
Have
Between the main body wing and the wing tip trailing edge wing,
A blade length direction slit extending through the blade in the blade thickness direction, extending from the blade tip toward the blade root side of the blade and terminating before reaching the blade root;
The blade penetrates the blade in the blade thickness direction, extends from the blade root side end of the blade length direction slit toward the trailing edge side of the blade and terminates before reaching the trailing edge, and has a slit width of approximately A chord slit which is zero,
Is divided,
The leading edge of the blade tip trailing edge blade portion is a virtual blade formed by smoothly extending a portion of the main body blade portion located on the leading edge side with respect to the blade tip trailing edge blade portion to the blade trailing edge. The rotor which is located in the front side or back side of a rotor rather than an airfoil center line of an end wing part.
The rotor according to claim 1, wherein the blade length direction slit extends linearly with a substantially constant slit width.
The leading edge of the blade tip trailing edge wing is located on the front side of the rotor from the airfoil center line of the virtual blade tip wing,
The airfoil center line of the virtual blade tip wing part and the airfoil center line of the blade tip trailing edge wing part are each curved so as to be convex on the back side of the rotor,
3. The rotor according to claim 1, wherein an angle θ formed by a smaller chord line of the virtual wing tip wing portion and a chord line of the wing tip trailing edge wing portion is 0 ° or more.
The airfoil center line of the virtual wing tip wing part and the airfoil center line of the wing tip trailing edge wing part each extend linearly,
The rotor according to claim 1 or 2, wherein an angle θ formed by a smaller chord line of the virtual wing tip wing part and a chord line of the wing tip trailing edge wing part is larger than 0 °.
The leading edge of the blade tip trailing edge wing is located on the back side of the rotor from the airfoil center line of the virtual blade tip wing,
The airfoil center line of the virtual blade tip wing part and the airfoil center line of the blade tip trailing edge wing part are each curved so as to be convex on the front side of the rotor,
3. The rotor according to claim 1, wherein an angle θ formed by a smaller chord line of the virtual wing tip wing portion and a chord line of the wing tip trailing edge wing portion is 0 ° or more.
The angle θ formed by the smaller chord line of the imaginary wing tip wing part and the chord line of the wing tip trailing edge wing part is less than 5 °, according to any one of claims 3 to 5. Rotor.
The blade length direction slit is located on a trailing edge side with respect to a chord center line connecting the chord line center points of the virtual blade tip wing portion, according to any one of claims 1 to 6. The described rotor.
The rotor according to any one of claims 1 to 7, wherein the wing has a plurality of wing tip trailing edge wings arranged at positions different from each other in a chord direction of the wing.