WO2023242949A1

WO2023242949A1 - Compressor rotor blade and compressor

Info

Publication number: WO2023242949A1
Application number: PCT/JP2022/023793
Authority: WO
Inventors: 亮介関; 英貴奥井
Original assignee: 三菱重工業株式会社; 三菱パワー株式会社
Priority date: 2022-06-14
Filing date: 2022-06-14
Publication date: 2023-12-21

Abstract

In a compressor rotor blade according to one embodiment, when the distance along the chord direction from a leading edge at a tip end of an airfoil part is within a range of 0.03-0.5 times of a chord length Lt at the tip end, the blade thickness Wt of the tip end at any position of the tip end is less than 0.3 times of the maximum blade thickness Wmax of the airfoil part at said position when the airfoil part is viewed from a span direction of the airfoil part. When viewed from the span direction, a camber line at the tip end is located between the camber line at a base end portion of the airfoil part and a pressure surface.

Description

Compressor blades and compressor

The present disclosure relates to a rotor blade of a compressor and a compressor.

For example, a compressor included in a gas turbine or the like has multiple stages of rows of rotor blades and rows of stator blades arranged alternately in the axial direction of the rotor. The compressed air is configured to generate high-pressure compressed air by passing through and compressing the stator blade row (for example, see Patent Document 1).

JP2018-168848A

For example, in an axial flow compressor such as the compressor described in Patent Document 1, the radially outer end (tip end) of a rotor blade and the inner circumferential surface of a stationary member such as a blade ring that faces the tip end in the radial direction. There is a clearance between them. This clearance is generally called tip clearance.
During operation of the compressor, leakage flow occurs from this tip clearance. From the viewpoint of improving compressor efficiency, it is required to suppress this leakage flow and to suppress pressure loss due to the leakage flow.

In view of the above-mentioned circumstances, at least one embodiment of the present disclosure aims to suppress loss due to leakage flow from a tip clearance in a compressor.

(1) A rotor blade of a compressor according to at least one embodiment of the present disclosure,
If the distance along the chord direction from the leading edge at the tip end of the airfoil portion is within the range of 0.03 times or more and 0.5 times or less of the chord length Lt at the tip end, any part of the tip end At the position, the blade thickness Wt of the tip end at the position is less than 0.3 times the maximum blade thickness Wmax of the airfoil at the position when the airfoil is viewed from the span direction of the airfoil. and
When viewed from the span direction, a camber line at the tip end is located between a camber line at the proximal end of the airfoil and the pressure surface.

(2) A compressor according to at least one embodiment of the present disclosure,
A rotor blade having the configuration of (1) above,
Equipped with

According to at least one embodiment of the present disclosure, loss due to leakage flow from the tip clearance in the compressor can be suppressed.

FIG. 1 is a schematic configuration diagram showing a gas turbine including a compressor according to some embodiments. FIG. 2 is a schematic diagram of rotor blades according to some embodiments of a compressor viewed from a circumferential direction centered on the axis of a rotor. FIG. 2 is a schematic diagram of a tip end of an airfoil portion of a rotor blade according to some embodiments of a compressor, viewed from the outside in a radial direction about the axis of a rotor. 4 is an example of a sectional view taken along the line IV-IV in FIG. 3. FIG. 4 is another example of a sectional view taken along the line IV-IV in FIG. 3. FIG. 4 is yet another example of a cross-sectional view taken along the line IV-IV in FIG. 3. FIG. 4 is yet another example of a cross-sectional view taken along the line IV-IV in FIG. 3. FIG. It is a graph which shows the relationship between the radial position of a boundary position and the efficiency of a compressor. It is a graph showing the relationship between the value obtained by dividing the blade thickness at the tip end by the tip clearance and the efficiency gain.

Hereinafter, some embodiments of the present disclosure will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as embodiments or shown in the drawings are not intended to limit the scope of the present disclosure, and are merely illustrative examples. do not have.
For example, expressions expressing relative or absolute positioning such as "in a certain direction,""along a certain direction,""parallel,""orthogonal,""centered,""concentric," or "coaxial" are strictly In addition to representing such an arrangement, it also represents a state in which they are relatively displaced by a tolerance or an angle or distance that allows the same function to be obtained.
For example, expressions such as "same,""equal," and "homogeneous" that indicate that things are in an equal state do not only mean that things are exactly equal, but also that there is a tolerance or a difference in the degree to which the same function can be obtained. It also represents the existing state.
For example, expressions that express shapes such as squares and cylinders do not only refer to shapes such as squares and cylinders in a strictly geometric sense, but also include irregularities and chamfers to the extent that the same effect can be obtained. Shapes including parts, etc. shall also be expressed.
On the other hand, the expressions "comprising,""comprising,""equipping,""containing," or "having" one component are not exclusive expressions that exclude the presence of other components.

(About gas turbine 1)
FIG. 1 is a schematic configuration diagram showing a gas turbine including a compressor according to some embodiments.
As shown in FIG. 1, a gas turbine 1 according to some embodiments includes a compressor 2 for generating compressed air as an oxidizing agent, and a gas turbine 2 for generating combustion gas using compressed air and fuel. It includes a turbine combustor 4 and a turbine 6 configured to be rotationally driven by combustion gas. In the case of the gas turbine 1 for power generation, a generator (not shown) is connected to the turbine 6, and the rotational energy of the turbine 6 is used to generate power.

A specific example of the configuration of each part in the gas turbine 1 according to some embodiments will be described.
The compressor 2 according to some embodiments includes a compressor casing 10, an air intake port 12 provided on the inlet side of the compressor casing 10 for taking in air, the compressor casing 10, and a turbine casing described below. The rotor 8 is provided so as to pass through the compressor casing 22, and various blades are arranged within the compressor casing 10. The various blades include an inlet guide blade 14 provided on the air intake port 12 side, a plurality of stator blades 16 fixed on the compressor casing 10 side, and a rotor arranged alternately with respect to the stator blades 16. 8. Note that the compressor 2 may include other components such as a bleed chamber (not shown). In such a compressor 2, air taken in from the air intake port 12 passes through the plurality of stationary blades 16 and the plurality of rotor blades 18 and is compressed, thereby becoming high-temperature and high-pressure compressed air. The high-temperature, high-pressure compressed air is then sent from the compressor 2 to the gas turbine combustor 4 in the subsequent stage.

In the gas turbine 1 according to some embodiments, the gas turbine combustor 4 is arranged within the casing 20. As shown in FIG. 1, a plurality of gas turbine combustors 4 may be arranged in a ring shape around the rotor 8 in the casing 20. Fuel and compressed air generated by the compressor 2 are supplied to the gas turbine combustor 4, and combustion gas, which is the working fluid of the turbine 6, is generated by burning the fuel. The combustion gas is then sent from the gas turbine combustor 4 to the subsequent turbine 6.

In the gas turbine 1 according to some embodiments, the turbine 6 includes a turbine casing 22 and various blades arranged within the turbine casing 22. The various blades include a plurality of stator blades 24 fixed to the turbine casing 22 side, and a plurality of moving blades 26 installed on the rotor 8 so as to be arranged alternately with respect to the stator blades 24. . Note that the turbine 6 may include other components such as outlet guide vanes. In the turbine 6, the rotor 8 is rotationally driven by the combustion gas passing through the plurality of stator blades 24 and the plurality of moving blades 26. As a result, a generator connected to the rotor 8 is driven.
An exhaust chamber 30 is connected to the downstream side of the turbine casing 22 via an exhaust casing 28 . After driving the turbine 6, the combustion gas is exhausted to the outside via the exhaust casing 28 and the exhaust chamber 30.

FIG. 2 is a schematic diagram of the rotor blades 18 according to some embodiments of the compressor 2 viewed from the circumferential direction centered on the axis AX of the rotor 8.
FIG. 3 is a schematic diagram of the tip end 181 of the airfoil portion 83 of the rotor blade 18 according to some embodiments of the compressor 2, viewed from the outside in the radial direction about the axis AX of the rotor 8.
FIG. 4A is an example of a cross-sectional view taken along the line IV-IV in FIG. 3, and shows a schematic cross-section of the vicinity of the tip end 181 of the airfoil portion 83 as viewed along the camber line LB.
FIG. 4B is another example of a cross-sectional view taken along the line IV-IV in FIG. 3, and shows a schematic cross-section of the vicinity of the tip end 181 of the airfoil portion 83 as viewed along the camber line LB.
FIG. 4C is still another example of the cross-sectional view taken along the line IV-IV in FIG. 3, and shows a schematic cross-section of the vicinity of the tip end 181 of the airfoil portion 83 viewed along the camber line LB.
FIG. 4D is still another example of the cross-sectional view taken along the line IV-IV in FIG. 3, and shows a schematic cross-section of the vicinity of the tip end 181 of the airfoil portion 83 as viewed along the camber line LB.

The rotor blade 18 according to some embodiments includes an airfoil portion 83 that extends in the radial direction (blade height direction) and has a pressure surface 83P and a suction surface 83S, and is provided on the radially inner side of the airfoil portion 83. It has a platform 84 and a blade root 85 provided on the radially inner side of the platform 84. The blade root 85 is embedded in the rotor 8.

The compressor 2 according to some embodiments includes a stationary member 11 that faces a radially outer end (tip end) 181 of the rotor blade 18 in the radial direction. In the compressor 2 according to some embodiments, the stationary member 11 is, for example, a blade ring 13.
In the compressor 2 according to some embodiments, a clearance exists between the tip end 181 of the rotor blade 18 and the inner peripheral surface 13i of the blade ring 13. This clearance is generally called tip clearance TC.
During operation of the compressor 2, leakage flow occurs from this tip clearance TC. From the viewpoint of improving the efficiency of the compressor 2, it is required to suppress this leakage flow and to suppress pressure loss due to the leakage flow.

Therefore, in the compressor 2 according to some embodiments, the rotor blades 18 are configured as follows.
As shown in FIG. 3, the distance along the chord direction, which is the extending direction of the chord line LA, from the leading edge 183 at the tip end 181 of the airfoil 83 is 0.03 times the chord length Lt at the tip end 181. The range R is 0.5 times or less.
In the rotor blade 18 according to some embodiments, at any position P of the tip end 181 within the above range R, the blade thickness Wt of the tip end 181 at the position P is such that the airfoil portion 83 is It is less than 0.3 times the maximum blade thickness Wmax of the airfoil portion 83 at the position P when viewed from the span direction of the airfoil portion 83. When viewed from the span direction, the camber line LB1 at the tip end 181 is located between the camber line LB2 at the base end (hub end 182) of the airfoil 83 and the pressure surface 83P.
Note that in cases where the cord length Lt at the tip end 181 and the cord length at the hub end 182 are different, the span direction and the radial direction do not strictly match, but FIG. Almost the same.
In FIG. 2, one of the line segments S along the span direction is illustrated by a chain line.

As a result of intensive studies by the inventors, it has been found that the smaller the blade thickness Wt of the tip end 181, the more effective is the suppression of pressure loss due to the separation of air from the tip end 181 on the suction surface 83S side and the reduction of the flow velocity reduction region. found. Moreover, the position where the leakage flow from the tip clearance TC starts from the leading edge 183 to the trailing edge 184 along the cord direction is such that the distance from the leading edge 183 along the cord direction is 0.0000000000000000000000000000000000000000000000000000000000000000000000000 00000000000000000000 water from the trailing edge 183 from the trailing edge 184 from the tip clearance TC in the tip direction. It is known that it exists within a range of 0.3 times or more and 0.5 times or less. In order to reduce loss due to leakage flow from the tip clearance TC, the cross-sectional shape of the airfoil portion 83 at this starting point position is aerodynamically important. Therefore, by making the thickness Wt of the tip end 181 at this starting point sufficiently thin with the rotor blades 18 according to some embodiments having the above configuration, loss due to leakage flow from the tip clearance TC can be reduced. Can be effectively suppressed.
Further, according to the rotor blade 18 according to some embodiments, since the end of the tip end 181 on the suction surface 83S side approaches the pressure surface 83P, the tip end 181 moves from the pressure surface 83P to the suction surface 83S. The convex warpage is reduced, and pressure loss due to leakage flow from the tip clearance TC can be suppressed.

Further, since the compressor 2 according to some embodiments includes the rotor blades 18 described above, the efficiency η of the compressor 2 can be improved.

As shown in FIGS. 4A, 4B, 4C, and 4D, in the rotor blade 18 according to some embodiments, at least within the range R, when viewed along the camber line LB, the pressure surface 83P is , it is preferable to extend linearly from the tip end 181 toward the hub end 182 side of the airfoil portion 83 along the span direction.
As a result, when viewed along the camber line LB, in the vicinity of the tip end 181, the pressure surface 83P is directed from the tip end 181 toward the hub end 182 side of the airfoil section 83 toward the outside of the airfoil section 83. In other words, the end of the tip end 181 on the suction surface 83S side comes closer to the pressure surface 83P, compared to the case where it extends convexly in the direction from the suction surface 83S toward the pressure surface 83P. Therefore, the convex warpage from the pressure surface 83P toward the negative pressure surface 83S at the tip end 181 is further reduced, and pressure loss due to leakage flow from the tip clearance TC can be suppressed.

In the above description, it was explained that the pressure surface 83P preferably extends linearly from the tip end 181 toward the hub end 182 side of the airfoil portion 83 along the span direction. It is not essential that the airfoil 83 extend linearly from the tip end 181 toward the hub end 182 of the airfoil 83 along the span direction. That is, in the rotor blade 18 according to some embodiments, when viewed along the camber line LB in at least a part of the region, the pressure surface 83P extends from the tip end 181 to the airfoil portion 83 along the span direction. It may extend in a curved manner toward the hub end 182 side.

As shown in FIGS. 4A, 4B, 4C, and 4D, in the rotor blade 18 according to some embodiments, at least within the range R, when viewed along the camber line LB, the suction surface 83S preferably includes a hub-side region 103 and a chip-side region 101 that is a region closer to the chip end 181 than the hub-side region 103. At least within the above range R, when viewed along the camber line LB, the negative pressure surface 83S is a tangent to the hub side region 103 at the boundary position Pb between the hub side region 103 and the tip side region 101 in the chip side region 101. It is preferably located between T1 and the pressure surface 83P.
This further reduces the convex warpage from the pressure surface 83P toward the negative pressure surface 83S at the tip end 181, and suppresses pressure loss due to leakage flow from the tip clearance TC.

For example, in the rotor blade 18 shown in FIG. 4A, at least within the above range R, when viewed along the camber line LB, the suction surface 831S in the tip side region 101 of the suction surface 83S is different from the suction surface 831S. It is formed so that a gentle curve connects the intersection position Px with the chip end 181 and the boundary position Pb.
For example, in the rotor blade 18 shown in FIG. 4B, at least within the above range R, when viewed along the camber line LB, the suction surface 831S in the tip side region 101 is a straight line between the intersection position Px and the boundary position Pb. It is formed to connect with.
For example, in the rotor blade 18 shown in FIG. 4C, at least within the above range R, when viewed along the camber line LB, the suction surface 831S in the tip side region 101 is located in an area relatively close to the intersection position Px and at the boundary position. The two regions are formed linearly so that the angular difference with the radial direction is relatively small in the region relatively close to Pb. In the rotor blade 18 shown in FIG. 4C, at least within the range R, when viewed along the camber line LB, the area between the two areas has a larger angular difference with respect to the radial direction than the two areas. It is formed in a straight line to increase its size.
For example, in the rotor blade 18 shown in FIG. 4D, at least within the range R, when viewed along the camber line LB, the suction surface 831S in the tip side region 101 is closer to the boundary than the region relatively near the intersection point Px. Each region is formed linearly so that the angular difference with the radial direction is smaller than that of a region relatively close to position Pb.
For example, in the rotor blade 18 shown in FIGS. 4C and 4D, at least within the above range R, when viewed along the camber line LB, the suction surfaces 831S in the tip side region 101 are adjacent to each other along the radial direction. Adjacent regions along the radial direction may be gently connected to each other so that the inclination angle gradually changes in the vicinity of the connection position between the regions.

In the rotor blade 18 according to some embodiments, the boundary position Pb is from the hub end 182 to the tip end when the hub end 182 of the airfoil portion 83 is set as 0% and the tip end 181 as 100%. It is preferable that the position is 70% or more of the distance to 181.

FIG. 5 is a graph showing the relationship between the radial position of the boundary position Pb and the efficiency η of the compressor 2.
In FIG. 5, E0 is the efficiency η of the compressor 2 when a conventional rotor blade without the tip side region 101 is used.
Note that the position of the negative pressure surface 83X at the tip end 181 of a conventional rotor blade without the tip side region 101 is indicated by a two-dot chain line in FIG.
In FIG. 5, E1 is the efficiency η of the compressor 2 when the boundary position Pb is set at 90% of the distance from the hub end 182 to the tip end 181, and E2 is the efficiency η of the compressor 2 when the boundary position Pb is set at 90% of the distance from the hub end 182 to the tip end 181. E3 is the efficiency η of the compressor 2 when the boundary position Pb is set at 80% of the distance from the hub end 182 to the tip end 181. This is the efficiency η of the compressor 2 when
In FIG. 5, E0 is the efficiency η of the compressor 2 when a conventional rotor blade without the tip side region 101 is used.

As a result of intensive study by the inventors, the efficiency of the compressor 2 is improved by moving the boundary position Pb between the hub side region 103 and the tip side region 101 toward the hub end 182 side and expanding the tip side region 101. However, it has been found that even if this boundary position Pb is moved to a position where it becomes smaller than 70% of the distance from the hub end 182 to the tip end 181, it becomes difficult to further improve the efficiency of the compressor 2. Further, as the boundary position Pb is moved closer to the hub end 182 side, the tip side region 101, that is, the region to be thinned, becomes larger, which affects the strength of the airfoil portion 83.
According to the rotor blades 18 according to some embodiments, the efficiency η of the compressor 2 can be improved while ensuring the strength of the airfoil portion 83.

As shown in FIG. 4A, in the rotor blade 18 according to some embodiments, at least within the range R, when viewed along the camber line LB, the suction surface 831S in the tip side region 101 extends in the span direction x When the blade thickness direction is the y-axis, the blade may extend along a curve C expressed by the following formula (A).
y=atan(x)...(A)

As a result, in the region near the chip end 181 in the chip side region 101, the slope of the suction surface 831S approaches the radial direction, and the suction surface 831S becomes a steep slope, thereby increasing the effect of improving efficiency η. can. In the area close to the boundary position Pb in the tip side area 101, the suction surface 831S can be smoothly connected from this area to the hub side area 103, making it difficult to disturb the air flow and suppressing pressure loss. Stress concentration due to a sharp change in shape in the shaped portion 83 can be suppressed.

As shown in FIGS. 4B, 4C, and 4D, in the rotor blade 18 according to some embodiments, at least within the range R, when viewed along the camber line LB, the tip side region 101 and the hub An angle θ1 between the suction surface 831S in the chip side region 101 and the suction surface 833S in the hub side region 103 of the suction surfaces 83S at the boundary position Pb with the side region 103 is greater than 160 degrees and less than 180 degrees. good.
If the angle θ1 between the negative pressure surface 831S in the chip side region 101 and the negative pressure surface 831S in the hub side region 103 is relatively small, the boundary position Pb between the chip side region 101 and the hub side region 103 will have a protruding shape. , pressure loss tends to increase. Further, since the blade thickness W increases from the tip end 181 toward the hub end 182 side in the tip side region 101, it is reasonable to set the angle θ1 to less than 180 degrees.
According to the rotor blades 18 shown in FIGS. 4B, 4C, and 4D, by setting the angle θ1 to more than 160 degrees and less than 180 degrees, pressure loss can be suppressed and the suction surface 83S near the boundary position Pb can be reduced. The shape can be made into a rational shape.

In the rotor blade 18 according to some embodiments, as shown in FIG. 4B, at least within the range R, when viewed along the camber line LB, the suction surface 831S in the tip side region 101 is located at the tip end 181. It may extend linearly from to the boundary position Pb between the chip side region 101 and the hub side region 103.
This makes it difficult to disturb the flow of air near the negative pressure surface 831S in the chip side region 101, so pressure loss can be suppressed.

As shown in FIGS. 4B, 4C, and 4D, in the rotor blade 18 according to some embodiments, at least within the above range R, when viewed along the camber line LB, the suction surface 831S and the tip end The angle θ2 between the negative pressure surface 831S and the chip end surface 181a forming the chip end 181 at the intersection position Px with the chip end 181 is preferably greater than 90 degrees and less than 110 degrees.

As a result of intensive studies by the inventors, it has been found that when the angle θ2 becomes 110 degrees or more, the efficiency improvement effect decreases significantly as the angle θ2 increases. Further, in order to increase the blade thickness W from the tip end 181 toward the hub end 182 side, the angle θ is preferably greater than 90 degrees.
According to the rotor blades 18 according to some embodiments, the efficiency η of the compressor 2 can be rationally improved.

In the moving blade 18 according to some embodiments, at least within the above range R, the blade thickness Wt of the tip end 181 is divided by the clearance TC between the inner peripheral surface 13i of the blade ring 13 and the tip end 181 (tip clearance TC). The value (Wt/TC) is preferably 1.5 or less.

FIG. 6 is a graph showing the relationship between the above-mentioned value (Wt/TC) and the efficiency gain representing the improvement rate of the efficiency η of the compressor 2. Note that the efficiency gain represents how much the efficiency η has improved compared to the conventional compressor, assuming that the theoretical efficiency of the compressor 2 is 100%.
As a result of intensive studies by the inventors, as mentioned above, the smaller the blade thickness Wt of the tip end 181, the more the pressure decreases due to the separation of air from the tip end 181 on the suction surface 83S (831S) side and the reduction in the flow velocity reduction area. It was found that the loss control effect was enhanced. Furthermore, in relation to the tip clearance TC, as shown in FIG. 6, it has been found that the efficiency gain is relatively large when the value obtained by dividing the blade thickness Wt at the tip end 181 by the tip clearance TC is 1.5 or less. did.
According to the rotor blades 18 according to some embodiments, the efficiency η of the compressor 2 can be further improved.

The present disclosure is not limited to the embodiments described above, and also includes forms in which modifications are made to the embodiments described above, and forms in which these forms are appropriately combined.

The contents described in each of the above embodiments can be understood as follows, for example.
(1) The rotor blade 18 of the compressor 2 according to at least one embodiment of the present disclosure includes an airfoil portion 83 having a pressure surface 83P and a suction surface 83S. If the distance along the chord direction from the leading edge 183 at the tip end 181 of the airfoil portion 83 is within the range R of 0.03 times or more and 0.5 times or less of the chord length Lt at the tip end 181, the tip end 181 At any position P, the blade thickness Wt of the tip end 181 at the position P is equal to the maximum blade thickness Wmax of the airfoil 83 at the position P when the airfoil 83 is viewed from the span direction of the airfoil 83. less than 0.3 times. When viewed from the span direction, the camber line LB1 at the tip end 181 is located between the camber line LB2 at the base end (hub end 182) of the airfoil 83 and the pressure surface 83P.

According to the configuration (1) above, by making the thickness Wt of the tip end 181 at the starting point sufficiently thin, it is possible to effectively suppress loss due to leakage flow from the tip clearance TC.
Further, according to the configuration (1) above, since the end of the tip end 181 on the suction surface 83S side approaches the pressure surface 83P, the tip end 181 is convex from the pressure surface 83P toward the suction surface 83S. The warpage is reduced, and pressure loss due to leakage flow from the tip clearance TC can be suppressed.

(2) In some embodiments, in the configuration of (1) above, at least within the range R, when viewed along the camber line LB, the pressure surface 83P extends from the tip end 181 along the span direction. It is preferable that the airfoil portion 83 extends linearly toward the hub end 182 side.

According to the configuration (2) above, when viewed along the camber line LB, in the vicinity of the tip end 181, the pressure surface 83P is shaped like an airfoil from the tip end 181 toward the hub end 182 side of the airfoil portion 83. Compared to the case where the tip extends convexly toward the outside of the portion 83, that is, in the direction from the suction surface 83S to the pressure surface 83P, the end of the chip end 181 on the suction surface 83S side is more closely aligned with the pressure surface 83P. Become closer. Therefore, the warpage that is convex from the pressure surface 83P toward the negative pressure surface 83S at the tip end 181 is further reduced, and pressure loss due to leakage flow from the tip clearance TC can be suppressed.

(3) In some embodiments, in the configuration of (2) above, at least within the range R, when viewed along the camber line LB, the negative pressure surface 83S is located between the hub side region 103 and the hub side region. It is preferable to include a chip side region 101 which is a region closer to the chip end 181 than 103 . At least within the above range R, when viewed along the camber line LB, the negative pressure surface 83S is a tangent to the hub side region 103 at the boundary position Pb between the hub side region 103 and the tip side region 101 in the chip side region 101. It is preferably located between T1 and the pressure surface 83P.

According to the configuration (3) above, the warpage that is convex from the pressure surface 83P toward the negative pressure surface 83S at the tip end 181 is further reduced, and pressure loss due to leakage flow from the tip clearance TC can be suppressed.

(4) In some embodiments, in the configuration of (3) above, the boundary position Pb is from the hub end 182 to the tip when the hub end 182 of the airfoil 83 is 0% and the tip end 181 is 100%. The position may be 70% or more of the distance to the end 181.

According to the configuration (4) above, the efficiency η of the compressor 2 can be improved while ensuring the strength of the airfoil portion 83.

(5) In some embodiments, in the configuration of (3) or (4) above, at least within the range R, when viewed along the camber line LB, the negative pressure surface 831S in the chip side region 101 is When the span direction is the x-axis and the blade thickness direction is the y-axis, it may extend along a curve C expressed by the following formula (A).
y=atan(x)...(A)

According to configuration (5) above, in the region near the chip end 181 in the chip side region 101, the inclination of the suction surface 831S approaches the radial direction and the suction surface 831S becomes a steep slope, thereby increasing the efficiency η. The improvement effect can be increased. In the area close to the boundary position Pb in the tip side area 101, the suction surface 831S can be smoothly connected from this area to the hub side area 103, making it difficult to disturb the air flow and suppressing pressure loss. Stress concentration due to a sharp change in shape in the shaped portion 83 can be suppressed.

(6) In some embodiments, in any of the configurations (3) to (5) above, at least within the range R, when viewed along the camber line LB, the tip side region 101 and the hub side The angle θ1 between the suction surface 831S in the chip side region 101 and the suction surface 833S in the hub side region 103 at the boundary position Pb with the region 103 is preferably greater than 160 degrees and less than 180 degrees.

If the angle θ1 between the negative pressure surface 831S in the chip side region 101 and the negative pressure surface 833S in the hub side region 103 is relatively small, the boundary position Pb between the chip side region 101 and the hub side region 103 will have a protruding shape. , pressure loss tends to increase. Further, since the blade thickness W increases from the tip end 181 toward the hub end 182 side in the tip side region 101, it is reasonable to set the angle θ1 to less than 180 degrees.
According to the configuration (6) above, by setting the angle θ1 to more than 160 degrees and less than 180 degrees, the shape of the negative pressure surface 83S near the boundary position Pb can be made into a rational shape while suppressing pressure loss. be able to.

(7) In some embodiments, in any of the configurations (3) to (6) above, at least within the range R, when viewed along the camber line LB, the negative pressure surface in the chip side region 101 is 831S may extend linearly from the chip end 181 to the boundary position Pb between the chip side region 101 and the hub side region 103.

According to the configuration (7) above, the air flow near the negative pressure surface 831S in the chip side region 101 is less likely to be disturbed, so pressure loss can be suppressed.

(8) In some embodiments, in any of the configurations (1) to (7) above, at least within the range R, when viewed along the camber line LB, the negative pressure surface 831S and the tip end 181 The angle θ2 between the negative pressure surface 831S and the chip end surface 181a forming the chip end 181 at the intersection position Px is preferably greater than 90 degrees and less than 110 degrees.

According to the configuration (8) above, the efficiency η of the compressor 2 can be rationally improved.

(9) The compressor 2 according to at least one embodiment of the present disclosure includes the rotor blade 18 having the configuration of any one of (1) to (8) above.

According to the configuration (9) above, the efficiency η of the compressor 2 can be improved.

(10) In some embodiments, the configuration of (9) above may include a stationary member (blade ring 13) facing the tip end 181 in the radial direction. At least within the above range R, the value obtained by dividing the blade thickness Wt of the tip end 181 by the clearance TC between the stationary member (blade ring 13) and the tip end 181 ((tip clearance TC)) is preferably 1.5 or less. .

As a result of intensive studies by the inventors, as mentioned above, the smaller the blade thickness Wt of the tip end 181, the more the pressure decreases due to the separation of air from the tip end 181 on the suction surface 83S (831S) side and the reduction in the flow velocity reduction area. It was found that the loss control effect was enhanced. Furthermore, in relation to the tip clearance TC, it has been found that the value obtained by dividing the blade thickness Wt of the tip end 181 by the tip clearance TC (Wt/TC) is preferably 1.5 or less.
According to the configuration (10) above, the efficiency η of the compressor 2 can be further improved.

1 Gas turbine 2 Compressor 11 Stationary member 13 Blade ring 18 Moving blade 83 Airfoil portion

83P Pressure surface

83S Suction surface 101 Tip side region 103 Hub side region 181 Tip end 182 Hub end 183 Leading edge 184 Trailing edge

Claims

an airfoil having a pressure surface and a suction surface;
If the distance along the chord direction from the leading edge at the tip end of the airfoil portion is within the range of 0.03 times or more and 0.5 times or less of the chord length Lt at the tip end, any part of the tip end At the position, the blade thickness Wt of the tip end at the position is less than 0.3 times the maximum blade thickness Wmax of the airfoil at the position when the airfoil is viewed from the span direction of the airfoil. and
When viewed from the span direction, the camber line at the tip end is located between the camber line at the proximal end of the airfoil and the pressure surface.
Compressor moving blades.
At least within the range, when viewed along the camber line, the pressure surface extends linearly from the tip end toward the hub end side of the airfoil along the span direction.
A rotor blade for a compressor according to claim 1.
At least within the range, when viewed along the camber line, the negative pressure surface is
including a hub side region and a chip side region that is a region closer to the chip end than the hub side region,
The compressor rotor blade according to claim 2, wherein the rotor blade of the compressor is located in the tip side region between a tangent to the hub side region at a boundary position between the hub side region and the tip side region and the pressure surface.
The boundary position is a position that is 70% or more of the distance from the hub end to the tip end when the hub end of the airfoil portion is 0% and the tip end is 100%.
A rotor blade for a compressor according to claim 3.
At least within the range, when viewed along the camber line, the suction surface in the tip side region is expressed by the following formula (A ) extending along the curve represented by
y=atan(x)...(A)
A rotor blade for a compressor according to claim 3 or 4.
At least within the range, when viewed along the camber line, the negative pressure surface in the tip side region and the negative pressure surface in the hub side region at a boundary position between the tip side region and the hub side region. The angle formed by is more than 160 degrees and less than 180 degrees,
A rotor blade for a compressor according to claim 3 or 4.
At least within the range, when viewed along the camber line, the negative pressure surface in the tip side region extends linearly from the tip end to the boundary position between the tip side region and the hub side region. do,
A rotor blade for a compressor according to claim 3 or 4.
At least within the range, when viewed along the camber line, the angle between the negative pressure surface and the chip end surface forming the chip end at the intersection of the negative pressure surface and the chip end is 90 degrees. more than 110 degrees,
A rotor blade for a compressor according to any one of claims 1 to 4.
The rotor blade according to claim 1,
A compressor equipped with
a stationary member radially opposed to the tip end;
Equipped with
At least within the range, the value obtained by dividing the blade thickness Wt at the tip end by the clearance TC between the stationary member and the tip end is 1.5 or less;
A compressor according to claim 9.