JPH09303103A - Closed loop cooling type turbine rotor blade - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a closed loop cooling type turbine rotor blade to perform effective cooling of a turbine blade, uniformize a metal temperature, increase cooling efficiency, and improve thermal efficiency. SOLUTION: A turbine rotor blade 20 is formed such that the interior of a turbine blade is formed in a hollow state and a blade cooling flow passage 25 is formed, and a cooling medium M is fed to a blade cooling flow passage 25 through a feed passage 26 from the bottom part of a blade-filled part 22 to cool the interior of the blade. A recovery passage 27 independent from the feed passage 26 is formed in the blade-filled part 22 and the cooling medium M to cool a blade effective part 21 through the blade cooling flow passage 25 is guided by the recovery passage 27 and recovered to the outside of the blade. The cooling medium M after cooling of the turbine blade is all recovered by the recovery passage 27 to employ a closed loop type cooling structure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a closed-loop cooling type turbine rotor blade having a hollow structure inside the cooling blade of a gas turbine and introducing a cooling medium from the root of the blade into the blade.

[0002]

2. Description of the Related Art A gas turbine used in a power plant is generally constructed as shown in FIG. 13, and a compressed air compressed by driving a compressor 2 provided coaxially with the turbine 1 is burned by a combustor 3 Of the combustion gas to burn the fuel in the liner portion 3a of the combustor 3, and the high temperature combustion gas resulting from the combustion is supplied to the transition piece 4 and the vanes 5 of the turbine 1.
And is guided to the moving blades 6 and is rotated to drive the turbine 1.

In order to improve the thermal efficiency of the gas turbine, it is known that the turbine inlet temperature should be high, and therefore, the turbine inlet temperature is increased. As the turbine inlet temperature rises, the need to use materials that can withstand high temperatures for the combustor 3 of the turbine 1, the stationary blades 5, and the moving blades 6 has increased, and heat-resistant superalloy materials have been developed and used as turbine parts. It is designed to be used.

The critical temperature of the heat resistant superalloy material currently used as a high temperature member of a gas turbine is 800 to 900.
Meanwhile, the turbine inlet temperature reaches about 1300 ° C., which is far above the limit temperature of the heat-resistant superalloy material. Therefore, in order to keep the turbine blades of the gas turbine within the limit temperature and maintain the reliability of the gas turbine,
The development of an internal cooling structure is required, and the use of cooling blades with a thermal barrier coating is essential.

In general, for cooling the turbine blade, the middle stage of the compressor 2 and a part of the discharged air are extracted, and the combustor 3 is used as a cooling medium.
Is often sent to the stationary blades 5 and the moving blades 6 of the gas turbine 1 by bypassing the gas. The higher the temperature of the combustion gas from the combustor 3, and thus the temperature of the gas passage, the more the cooling medium M is required.
Since the gas passage is bypassed, it does not contribute to the generation of output until the gas is mixed in the gas passage after cooling the turbine blade.

Therefore, as the amount of the cooling medium M increases, the supply amount to the combustor decreases, the thermal efficiency of the gas turbine decreases, and the higher thermal efficiency obtained by increasing the inlet temperature of the gas passage is cooled. There is a possibility that the increase in the medium M may offset each other. Therefore, in order to increase the thermal efficiency of the gas turbine, it is important to efficiently cool the turbine blades with as little cooling medium M as possible.

FIG. 14 shows a vertical section of a cooling blade 6 of a typical gas turbine of 1300 ° C. class which is currently adopted.
The moving blade 6 is composed of a blade effective portion 7, a blade implanting portion 8, a blade shank portion 9 and a blade platform 10 to which the blade effective portion 7 is attached. The cooling medium M has three supply passages 11a, 1a.
It is divided into 1b and 11c and supplied. Each supply passage 11
In the blade effective portion 7, a, 11b, and 11c form throttles to enhance the convection cooling effect, and increase the flow velocity of the cooling medium M and provide the turbulent flow promoting ribs 13 as throttle cooling flow passages 12a, 12b, and 12c, respectively. It promotes turbulence in the flow and makes the temperature uniform.

The cooling medium M that has flowed into the leading edge supply passage 11a of the moving blade 6 flows from the inner diameter side of the blade effective portion to the outer diameter side while performing internal convection cooling and is blown to the outside from the film cooling hole 15. A film film is formed on the front edge side of the moving blade 6 to protect the blade from a high temperature mainstream gas (combustion gas). Further, the cooling medium M flowing into the turbine axial direction central portion supply passage 11b of the moving blade 6 flows from the inner diameter side of the blade effective portion to the outer diameter side, then is inverted and guided again to the inner diameter side. Convection cooling is performed while forming a meandering flow path (zigzag flow path) called a so-called serpentine, and is similarly blown from the film cooling hole 15 to the outside on the back side of the turbine blade to protect the blade from high-temperature mainstream gas. Similarly, in the trailing edge portion supply passage 11c of the moving blade 6, the cooling medium M is convectively cooled while flowing to the outer diameter side, and flows from the trailing edge blowing hole 16 to the outside.

[0009]

In a gas turbine plant, it is effective to raise the turbine inlet temperature in order to improve the thermal efficiency of the gas turbine. But,
When the gas turbine inlet temperature exceeds 1300 ° C., the required cooling medium amount (currently, the discharge air of the compressor is the mainstream) increases significantly.

In the case of the open-loop type gas turbine cooling structure in which the cooling medium M after cooling the moving blades 6 is blown into the combustion gas, the increase of the cooling medium M causes dilution of the gas temperature and loss of mixing with the mainstream gas (combustion gas). However, there is a possibility that the performance of the gas turbine may deteriorate due to the increase in pumping power. Further, an increase in the amount of cooling medium also causes a decrease in the thermal efficiency of a power plant using a gas turbine. Furthermore, for poor fuel such as impurities mixed, the small holes formed on the blade surface will be clogged,
Not applicable because it impairs the film cooling function.

Further, the following problems are raised in cooling the turbine blade.

(1) The leading edge portion and the trailing edge portion of the turbine blade have a large heat transfer coefficient with the mainstream gas side, and due to the blade structure, the heat transfer area on the cooling side is excessive with respect to the heat transfer area on the blade surface. The temperature cannot be increased and cooling is difficult, and the metal temperature tends to be relatively higher than other turbine blade parts. In particular, since the cooling passage area cannot be increased at the trailing edge portion of the turbine blade, the amount of heat that flows in becomes large relative to the flow rate of the cooling medium M, and the flow rate becomes relatively large with respect to other turbine blade portions as shown in FIG. The pressure drop and the temperature rise of the cooling medium M in the direction increase, and the cooling capacity decreases.

(2) Since the temperature of the cooling medium M rises due to the blowing of the cooling medium M at the tip of the turbine blade, effective cooling becomes difficult and the metal temperature tends to be relatively high.

(3) The heat transfer coefficient distribution on the blade surface of the turbine blade is
As shown in FIG. 16, there is a large difference between the back side and the ventral side of the turbine blade, and conventionally, the blade surface metal temperature is uniformly cooled by using the film cooling on the blade back side together. However, in order to prevent the deterioration of the performance of the gas turbine due to the mixing of the cooling medium M blown out from the film cooling holes and the mainstream gas, the cooling medium M
If convection cooling from the inside of the turbine blade is done by eliminating the film cooling caused by the blowout of air, if the metal temperature on the back side of the turbine blade is tried to cool within the allowable value, the ventral side will be overcooled and the temperature difference between the backside and the ventral side will be Grows larger. This may lead to an increase in the amount of cooling medium that is useless for cooling the turbine blade and an increase in thermal stress.

The present invention has been made in consideration of the above-mentioned circumstances, and it is intended to effectively cool the turbine blade to make the metal temperature uniform and to increase the cooling efficiency to improve the thermal efficiency. An object is to provide a closed-loop cooled turbine blade.

Another object of the present invention is to provide a closed loop cooling type turbine engine which performs good cooling even when the combustion gas temperature is high, is applicable to poor fuel, and does not impair the blade cooling function. To provide wings.

[0017]

In order to solve the above-mentioned problems, a closed-loop cooling type turbine rotor blade according to the present invention is provided.
As described in claim 1, the inside of the blade of the turbine blade is made hollow to form a blade cooling flow path, and the cooling medium is supplied to the blade cooling flow path from the bottom portion of the blade implantation portion through the supply passage, In a turbine rotor blade for cooling a turbine blade, a recovery passage for recovering a cooling medium from the blade cooling passage to the outside of the turbine blade is provided in the blade implantation portion independently of the supply passage, and the cooling passage cools the turbine blade after cooling. It is configured to collect the entire amount of the medium.

Further, in order to solve the above-mentioned problems, the closed-loop cooling type turbine rotor blade according to the present invention, as described in claim 2, supplies the cooling medium formed in the blade implanting portion of the turbine blade. The passage is provided at either the leading edge side or the trailing edge side of the turbine blade, and the cooling medium recovery passage is independently provided at the other side.

Further, in order to solve the above-mentioned problems,
A closed-loop cooling type turbine rotor blade according to the present invention is claim 3.
As described above, the blade cooling flow passage formed inside the blade of the turbine blade is formed in a flow passage structure in which the cooling medium from the supply passage can be first supplied to the leading edge portion and the trailing edge portion of the blade effective portion. It was done.

Further, in order to solve the above-mentioned problems, in the closed-loop cooling type turbine rotor blade according to the present invention, as described in claim 4, the supply passage formed in the blade implanting portion of the turbine blade is The blade shank portion is branched into a front supply passage and a rear supply passage, and one of the branched supply passages intersects with the recovery passage at the blade shank portion.

In order to solve the above-mentioned problems, according to the closed-loop cooling type turbine rotor blade of the present invention, as described in claim 5, the blade cooling flow path formed in the blade effective portion of the turbine blade is , A front cooling flow passage and a rear cooling flow passage, the front cooling flow passage communicates with the front supply passage of the blade shank portion, flows in the blade effective portion on the leading edge side of the turbine blade in the outer diameter direction, and the blade tip portion While the flow direction is reversed by the flow path structure toward the inner diameter direction, the rear cooling flow path communicates with the rear supply passage of the blade shank and the effective blade portion on the trailing edge side of the turbine blade in the outer diameter direction. To the inner side of the turbine blade by reversing the flow direction at the blade tip, and the front cooling channel is formed in the return channel formed near the blade center between the leading and trailing edges of the turbine blade. And the rear cooling flow passage are joined together and communicated with the recovery passage.

Further, in order to solve the above-mentioned problem,
A closed-loop cooled turbine blade according to the present invention is defined in claim 6.
As described above, the return flow path formed near the central portion of the blade between the leading edge and the trailing edge of the turbine blade forms a merging portion on the inlet side formed in the blade tip portion, and a cooling medium is formed at this merging portion. Is provided with a guide wall that guides the flow of the fluid in the inner diameter direction.

Further, in order to solve the above-mentioned problems, a closed-loop cooling type turbine rotor blade according to the present invention has, as described in claim 7, a turbine blade having a blade leading edge side cavity and a central cavity in a blade platform. , And a blade trailing edge side cavity are formed, and a tip cavity is formed in the blade tip portion, while the cooling medium supply passage is branched to communicate with the blade leading edge side cavity and the blade trailing edge side cavity, and the central cavity is A plurality of cooling flow passages are communicated with the recovery passageway and extend from the blade leading edge side, center and blade trailing edge side cavities along the blade surface of the blade effective portion to communicate with the tip cavity of the blade tip portion. .

On the other hand, in order to solve the above-mentioned problems, in the closed-loop cooling type turbine rotor blade according to the present invention, as described in claim 8, the blade cooling flow path of the turbine blade is an outer cooling flow at the blade shank portion. The outer cooling flow path extends toward the blade tip part from the leading edge of the blade effective part while changing its direction at the blade tip part from the blade leading edge side to the blade trailing edge side. After extending, it is formed so as to change its direction on the trailing edge side of the blade tip portion and to extend the trailing edge portion of the blade effective portion toward the blade shank portion, and the inner cooling flow passage is zigzag inside the outer cooling flow passage. The flow path structure has a uniform flow shape, and the outer cooling flow path and the inner cooling flow path join together at the blade shank portion and communicate with the recovery path.

On the other hand, in order to solve the above-mentioned problems, a closed-loop cooling type turbine rotor blade according to the present invention has, as described in claim 9, a blade back side cavity and a blade vent side inside a blade platform of a turbine blade. It has a cavity and connects the cooling medium supply passage to one of the blade back side and the blade side cavity and the cooling medium recovery passage to the other cavity, while the blade is effective from the blade back side and the blade side cavity. The blade back side cooling passage and the blade back side cooling passage extend respectively along the blade surface of the portion and communicate with the tip cavity formed in the blade tip portion.

Further, in order to solve the above-mentioned problems,
A closed-loop cooled turbine blade according to the present invention is defined in claim 1.
As described in No. 0, the plurality of cooling channels arranged along the blade surface of the blade effective portion of the turbine blade are provided with ribs for promoting turbulent flow of the cooling medium on the inner wall on the blade surface side of the blade effective portion. It is a thing.

Further, in order to solve the above-mentioned problems, a closed-loop cooled turbine blade according to the present invention has a cavity and a blade tip formed in a blade platform of a turbine blade as described in claim 11. The plurality of cooling passages of the blade effective portion communicating with the tip cavity formed in the portion are provided with a passage narrowing portion in at least one of the passage inlet portion and the passage outlet portion.

[0028]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

[First Embodiment] FIG. 1 is a vertical sectional view showing a first embodiment of a closed-loop cooling type turbine rotor blade according to the present invention, and FIG. 2 is a horizontal sectional view taken along line II-II of FIG. 3 is a sectional view taken along line III-III in FIG.

The closed loop cooled turbine blade 20 is shown in FIG.
Similar to the conventional gas turbine shown in FIG. 3, a large number are planted along the circumferential direction on the turbine shaft of the gas turbine. The turbine rotor blade 20 includes a blade effective portion 21 that forms a turbine blade (blade) that allows a high-temperature mainstream gas (combustion gas) to pass through and expands the blade, and a blade that is planted in a rotor disk (not shown) of the turbine shaft. Wing implant part 22 as a root part and wing effective part 2
1 and a wing shank portion 23 connecting the wing implant portion 22,
The blade effective part 21 is attached to the blade platform 24.

The inside of the turbine rotor blade 20 has a hollow shape to form a passage of the cooling medium M, and a blade cooling flow passage 25 for cooling the turbine blade is formed inside the blade. Further, the blade implanting portion 22 has an axial direction (longitudinal direction) of the turbine blade.
Two passages 26, 27 are formed which extend to the. One of the passages is independently formed in the supply passage 26 for the cooling medium M on the leading edge side of the turbine moving blade 20, and the other passage is formed in the recovery passage 27 for the cooling medium M independently on the trailing edge side of the turbine moving blade 20.
The cooling medium M may be air, steam or water.

The supply passage 26 for the cooling medium M has a blade-implanted portion 22.
Of the cooling medium M extending in the longitudinal direction (outer diameter direction) of the turbine blade from the bottom portion of the
Is divided into a front side supply passage 26a and a rear side supply passage 26b so that the air can be supplied to the front edge portion and the rear edge portion of the blade effective portion 21. The rear side supply passage 26b three-dimensionally intersects with the recovery passage 72 for the cooling medium M at the blade shank portion 23, and makes the supply passage 26 and the recovery passage 27 independent.

The front side supply passage 26a communicates the leading edge portion of the turbine blade of the blade effective portion 21 with the leading edge passage 28 of the blade cooling passage 25 extending in the outer radial direction (outer side in the longitudinal direction of the turbine blade). The leading edge flow passage 28 extends inwardly (inwardly in the longitudinal direction of the turbine blade) by reversing the direction by 180 degrees at the blade tip portion 29, which is the blade tip portion of the blade effective portion 21, and further serves as the blade platform 24. At the root portion, the direction is reversed again by 180 degrees, and it is extended in the outer diameter direction and extends in a zigzag shape.
9 is connected to the return flow path 30. The return flow passage 30 is located near the central portion of the blade between the leading edge and the trailing edge of the turbine blade and the blade effective portion 21.
Of the blade root portion 24 and communicates with the recovery passage 27 at the blade root portion 24.

On the other hand, similarly, the rear side supply passage 26b also communicates the trailing edge portion of the turbine blade of the effective blade portion 21 with the trailing edge passage 31 of the blade cooling passage 25 extending in the outer diameter direction (outward in the longitudinal direction). . The trailing edge passage 31 is formed by the blade tip portion 29 of the blade effective portion 21.
The direction is reversed by 180 degrees and extends toward the inner diameter direction (the inner side in the longitudinal direction). Further, the root portion, which is the blade platform 24, reverses the direction again by 180 degrees and is extended in the outer diameter direction and extends in a zigzag shape. The blade tip portion 29 joins the return passage 30 and faces the inner diameter direction, and is guided to the recovery passage 27 for the cooling medium M. Blade tip part 2 which is the inlet side of the return flow path 30
A guide wall 32 is provided at the merging portion of 9 to guide the cooling medium M so that the cooling medium M smoothly merges. Guide wall 32
In order to smoothly guide the flow of the cooling medium M, is projected in a tapered shape in the inlet portion of the return passage 30 to form a smoothly curved guide surface.

In this turbine rotor blade 20, two zigzag cooling flow passages 33 and 34 are formed independently on the front side and the rear side of the blade effective portion 21 of the turbine blade, and a closed loop type blade cooling flow passage 25 is formed. I am configuring. This turbine rotor blade 20
In the two cooling passages 33 and 34 of the blade cooling passage 25 formed in the blade effective portion 21 of the turbine blade, the cooling medium M for cooling the turbine blade is first fed to the leading edge passage 28 and the trailing edge. Channel 3
1, the front and rear edges of the turbine blade are actively cooled.

Front and rear cooling channels 3 of the turbine blade
A plurality of turbulent flow promoting ribs 13 are provided at 3, 34 at intervals in the flow channel longitudinal direction so as to cross the cooling flow channel.
The turbulent flow promoting rib 13 also serves as a throttle for increasing the convective cooling effect of the blade effective portion 7, and the turbulent flow promoting rib 13 increases the flow velocity of the cooling medium M flowing in the cooling flow passages 33 and 34 while flowing. Of the cooling medium M is promoted, and the temperature of the cooling medium M is made uniform.

Next, the normal operation of the closed-loop cooling type turbine blade will be described.

The closed-loop cooled turbine blade 20 is
Many are circumferentially implanted in a rotor disk (not shown) formed on the turbine shaft of the gas turbine. The turbine rotor blade 20 is opposed to a turbine rotor blade (not shown) in the turbine axial direction to form a turbine stage.

The turbine rotor blade 20 is cooled by the cooling medium M during the operation of the gas turbine. At the time of cooling the gas turbine, the cooling medium M supplied to the supply passage 26 of the blade implanting portion 22 is divided into the front supply passage 26a and the rear supply passage 26b by the blade shank portion 23, and the front side of the blade cooling flow passage 25 is obtained. The cooling channel 33 and the rear cooling channel 34 are respectively guided.

Cooling medium M guided to the front side supply passage 33
Is first guided to the leading edge flow path 28 of the blade effective portion 21, flows in the outer diameter direction (outer side of the turbine blade longitudinal direction) while cooling the leading edge portion of the blade effective portion 21, and the flow is 180 at the blade tip portion 29. Flip it once. The cooling medium M reversed in the blade tip portion 29 subsequently flows in the inner diameter direction, and then flows in a zigzag shape through the front side cooling flow path 33 while being reversed again in the blade root portion 24, from the blade leading edge side of the turbine blade. The turbine rotor blade 20 was convectively cooled toward the middle portion.

On the other hand, the cooling medium M guided to the rear side supply flow path 34 is also first introduced to the trailing edge flow path 31 of the blade effective portion 21 while being cooled while cooling the rear edge portion of the blade cooling portion 21. It flows in the radial direction (outer side in the longitudinal direction of the turbine blade), and the flow is reversed by 180 degrees at the blade tip portion 29. The cooling medium M whose flow is reversed in the blade tip portion 29 subsequently flows in the inner diameter direction,
Furthermore, it is reversed again at the blade root portion 24 and flows in the outer diameter direction,
The turbine cooling blade 20 flows in the rear cooling flow path 34 in a zing-zag manner to convectively cool the turbine rotor blade 20 from the blade trailing edge side of the turbine blade to the blade intermediate portion.

The cooling medium M convectively cooling the turbine rotor blade 20 through the front and rear cooling flow passages 33, 34 formed in the blade effective portion 21 of the turbine blade finally merges in the blade tip portion 29. While being guided by the return flow path 30 which is a confluent flow path, the flow is changed in the inner diameter direction (the inner side in the longitudinal direction of the turbine blade), and the blade effective portion 21 in the vicinity of the blade central portion is cooled while the recovery passage for the cooling medium M is provided. Guided to 27. The entire amount of the cooling medium M is taken out of the recovery passage 27 to the outside of the turbine blade.

In this turbine rotor blade 20, since the blade cooling flow path 25 in which the cooling medium M is closed is formed inside the blade and the cooling medium M is not blown out from the blade effective portion 21 to the outside of the blade, the mainstream gas ( It is not guided to the gas passage of the combustion gas). The cooling medium M effectively cools the entire blade of the turbine blade in a closed loop without being blown out into the gas passage of the mainstream gas.

The turbine rotor blade 20 first supplies the cooling medium M, which has not yet risen in temperature, to the leading edge portion and the trailing edge portion of the turbine blade, so that the outer surface of the turbine blade having a large heat transfer coefficient,
In particular, the outer surfaces of the leading and trailing edges of the blade can be efficiently convectively cooled first, effectively preventing the occurrence of local hot spots, while reducing the metal temperature of the entire blade of the turbine blade. Cools uniformly with less cooling medium.

Further, in this turbine rotor blade 20,
A zigzag blade cooling channel 2 is provided in the blade effective portion 21 of the turbine blade.
5, the cooling medium M flows in the front and rear cooling flow paths 33, 34 of the blade effective portion 21 in a zigzag manner to be counter-cooled, and then the flow is directed in the inner diameter direction by the guide wall 32 provided at the confluence portion. After aligning (inside the turbine blade in the longitudinal direction), they can be smoothly merged. The cooling medium M guided from the merging portion to the return flow passage 30 can avoid a flow (merging) that cancels out the dynamic pressure of the cooling medium M flowing through the cooling flow passages 33 and 34, and the pressure loss of the cooling medium M. Can be suppressed.

FIG. 4 shows a closed-loop cooled turbine blade 20.
9 shows a modification of the first embodiment of FIG.

The turbine rotor blade 20 shown in this modified example
Is a supply passage 26A for the cooling medium M on the trailing edge side in the turbine axis direction of the blade-implanted portion 22 of the turbine blade, and a recovery passage 27A on the leading edge side, and is provided in a turbine rotor (not shown) of the turbine shaft. The supply passage 26A and the recovery passage 27A can be selected according to the flow passage form of the formed cooling medium M.

Another structure is the turbine rotor blade 2 shown in FIG.
Since it is not different from 0, the same reference numerals are given and description thereof is omitted.

[Second Embodiment] FIG. 5 is a vertical sectional view showing a second embodiment of a closed-loop cooling type turbine rotor blade according to the present invention. FIGS. 6 and 7 are VI-VI lines in FIG. And VI
FIG. 7 is a sectional view taken along the line I-VII.

The closed-loop cooling type turbine rotor blade 20A shown in the second embodiment has the same external shape and structure as the turbine rotor blade 20 shown in FIG. 1, and the passage configuration of the blade implanting portion 22 and blade shank portion 23. Since they are the same, the same parts are denoted by the same reference numerals and the description thereof will be omitted.

The turbine rotor blade 20A shown in FIG. 5 has three independent cavities 37a, 37b, 37c in the blade platform (blade root portion) 24 of the turbine blade from the blade leading edge to the blade trailing edge. While forming sequentially, the common tip cavity 38 is formed in the blade tip portion 29. Blade leading edge side cavity 37 formed in the blade platform 24
The front side supply passage 26a and the rear side supply passage 26b branched from the common passage 26 for the cooling medium M communicate with the a and the blade trailing edge side cavity 37c, respectively. A recovery passage 27 for the cooling medium M communicates with the intermediate cavity 37b.

On the other hand, the blade platform 24 of the turbine blade
Cooling holes 39a, 39 extending in the longitudinal direction of the blade effective portion 21 from the cavities 37a, 37b, 37c formed therein.
A plurality of b and 39c are formed in a row along the turbine blade surface to form a blade cooling flow path 39. Blade cooling channel 3
Each of the cooling holes 39a, 39b, 39c forming 9 is roughly divided into a leading edge side, an intermediate side and a trailing edge side of the turbine blade, and includes a leading edge side cooling hole row 39A, an intermediate cooling hole row 39B and a trailing edge side cooling hole row 39C. It constitutes a cooling channel. The cooling flow path composed of these cooling hole arrays 39A, 39B, 39C communicates with a common tip cavity 38 provided in the blade tip portion 29.

In this turbine rotor blade 20A, as shown in FIG.
As shown in FIG. 3, the leading edge side cooling hole row 39A includes three cooling holes 3
9a, the intermediate cooling hole row 39B has seven cooling holes 39b,
The trailing edge side cooling hole row 39C discloses a configuration example of a cooling flow path provided with four cooling holes 39c in a row, but the number of cooling holes forming each cooling flow path is as illustrated in FIG. Not limited to. Further, the tip cavity 38 is shared,
FIG. 5 shows an example in which one blade is formed, but the number is not necessarily limited to one, and may be formed separately in the leading edge side cavity and the trailing edge side cavity at approximately the blade central portion.

Further, in each of the cooling holes 39a, 39b, 39c formed in the blade effective portion 21 of the turbine blade, the turbulent flow promoting rib 35 for the cooling medium M is provided only on the inner wall facing the blade outer surface side of the turbine blade. The flow passage restricting portions 40, 40 are formed at the communicating portions of the cooling holes 39a, 39c of the front and rear edge side cooling hole rows 39A, 39C and the tip cavity 38, respectively. In addition, each cooling hole 39 of the intermediate cooling hole row 39B
b and the flow path throttle portion 41 are also formed at the connecting portion between the blade root portion 24 and the intermediate cavity 37b.
At 0 and 41, the flow passage cross-sectional areas of the cooling holes 39a, 39b and 39c are narrowed to accelerate the flow velocity. The flow path throttle portions 40 and 41 are formed by forming bulging portions at the ends of the partition wall 43 of the cooling holes 39a, 39b and 39c.

The flow passage restricting portions 40 and 41 may be provided in at least one of the flow passage inlet portion and the flow passage outlet portion of each of the cooling holes 39a, 39b and 39c forming a plurality of cooling passages.

Cooling of the turbine rotor blade 20A during operation of the gas turbine is performed as follows.

When cooling the gas turbine, a cooling medium M such as air or steam is supplied to the turbine rotor blade 20A. Supply passage 26 of blade implanting portion 22 of turbine rotor blade 20A
The cooling medium M guided by is branched into the front and rear supply passages 26a and 26b at the blade shank portion 23, and is made to flow into the blade leading edge side and the blade trailing edge side cavities 37a and 37c.

The cooling medium M guided to the blade leading edge side cavity 37a is guided from this cavity 37a to the leading edge side cooling hole row 39A which is the leading edge side cooling passage of the blade effective portion 21,
The cooling holes 39a of the cooling hole row 39A flow in the outer diameter direction (outward in the longitudinal direction of the turbine blade) and are guided to the tip cavity 38 of the blade tip portion 29.

On the other hand, the cooling medium M guided to the trailing edge side cavity 37c is similarly guided to the trailing edge side cooling hole row 39C which is the trailing edge side cooling flow passage of the blade effective portion 21, and this cooling hole row 3
9C of each cooling hole 39c flows in the outer diameter direction and the blade tip portion 2
9 to the tip cavity 38.

While the cooling medium M flows in the leading edge side cooling hole row 39A and the trailing edge side cooling hole row 39C of the blade effective portion 21 in the radial direction, the leading edge portion and the trailing edge portion of the turbine blade are first positively positively applied from the inside. Convection cooling.

At this time, the cooling holes 39a and 39b of the cooling hole arrays 39A and 39C are provided with the turbulent flow promoting ribs 35, and the turbulent flow is promoted by the rib effect, and the temperature is made uniform. Increasing the effect of convection cooling.

The cooling medium M, which has been cooled while flowing in the leading and trailing edges of the turbine blade in the radial direction, is guided to the tip cavity 38 of the blade tip portion 29, and this tip cavity 3
After joining at 8, each cooling hole 39b of the intermediate cooling hole row 39B
Flowing in the inner diameter direction, is convectively cooled while increasing the cooling effect by the turbulent flow promoting ribs 35, is guided to the recovery passage 27 via the intermediate cavity 37b of the blade root portion 24, and from the recovery passage 27 to the outside of the blade of the turbine blade. Taken out.

According to the closed-loop cooling type turbine rotor blade 20A, the cooling medium M, which has not yet risen in temperature, passes through the blade-implanting portion 22 and the blade shank portion 23, which are the blade root portions, and the cooling holes on the leading edge side of the blade effective portion 21. Row 39A and trailing edge side cooling hole row 39
The turbulent flow promoting rib 35 positively guides the leading edge portion and the trailing edge portion of the turbine blade while being first guided by C and flowing in the cooling holes 39a and 39c of the cooling hole rows 39A and 39C in the outer diameter direction. Cooling from inside. Therefore, similarly to the turbine rotor blade 20 of the first embodiment, the turbine rotor blade 20A shown in FIG. 5 effectively cools the leading edge portion and the trailing edge portion of the turbine blade, which is difficult to cool, so that the blade is effective. It is possible to uniformly cool the entire part. Moreover, the branched cooling medium M
Can be collected from one place.

This closed-loop cooled turbine blade is shown in FIG.
As shown in FIG. 5, at least the cooling holes 39a, 39b, 39c facing at least the blade surfaces of the turbine blades are provided with the turbulent flow promoting ribs 35 to increase the cooling area capable of heat exchange, while the cooling holes 39a, 39b, 39c are provided. Since the flow of the cooling medium M passing therethrough is disturbed and the turbulent flow is promoted for uniform cooling, the heat transfer coefficient of the cooling side surface facing the blade surface of the turbine blade can be increased, and the cooling medium M The flow rate can be reduced.

Cooling holes 39a, 39 of cooling hole rows 39A, 39B, 39C formed in the blade effective portion 21 of the turbine blade.
Since the turbulent flow promoting ribs 35 are not provided on the inner side surfaces of the b and 39c, the increase in the pressure loss of the cooling medium M passing through the cooling holes 39a, 39b and 39c can be minimized. Further, the cooling hole rows 39A, 39 formed in the blade effective portion 21
The cooling holes 39a, 39b, 39c of B and 39C constitute the cooling flow path 39, but the cooling holes 39a, 39b, 3
By previously adjusting the throttle amount of the flow passage throttle portions 40, 41 formed in 9c, each cooling hole 39a, 39b, 39c.
The flow rate of the cooling medium M flowing inside can be adjusted according to the blade surface heat transfer coefficient of the turbine blade, and the metal temperature of the turbine rotor blade can be made more uniform.

In this turbine moving blade, an example is shown in which the supply passage 26 for the cooling medium M is formed on the front side of the blade implanting portion 22 of the turbine blade, and the recovery passage 27 is formed on the rear side of the blade. The passage 26 and the recovery passage 27 may be configured as shown in FIG.

[Third Embodiment] FIG. 8 is a vertical sectional view showing a third embodiment of a closed-loop cooling type turbine rotor blade according to the present invention.

The turbine rotor blade 20 shown in this embodiment
B is substantially the same as the turbine rotor blade 20 shown in FIG. 1 in overall structure, and therefore, corresponding parts will be denoted by the same reference numerals and description thereof will be omitted.

The turbine rotor blade 20B shown in FIG. 8 has a hollow shape for forming the blade cooling flow passage 25 of the cooling medium M inside the turbine blade, and has two passages in the blade implanting portion 22. 26 and 27 are formed along the axial direction of the turbine. The two passages 26, 27 are arranged in parallel so as to extend along the axial direction (longitudinal direction) of the turbine blade, while one of the passages is a supply passage 26 for the cooling medium M on the leading edge side of the turbine rotor blade 20B. The other passage is a recovery passage 27 for the cooling medium M and is formed on the trailing edge side of the turbine rotor blade 20B.

The blade cooling section passage 25 communicating with the supply passage 26 for the cooling medium M has two cooling passages 45 from the blade platform 24 on the inlet side of the blade shank portion 23, that is, the blade effective portion 21 of the turbine blade. It is branched to 46. The first cooling flow passage 45 is formed as an outer cooling flow passage that flows on the turbine blade leading edge / rear edge side of the blade effective portion 21, and the second cooling flow passage 46 is formed as an inner cooling flow passage that flows in the turbine blade intermediate portion. To be done.

The outer cooling flow passage 45 is provided at the blade shank portion 23 or the blade platform 24 on the blade root side by the supply passage 26.
And extends in the outer diameter direction of the turbine blade leading edge portion of the blade effective portion 21 to reach the blade tip portion (blade tip portion) 29. At the blade tip portion 29, the blade tip portion 29 extends from the blade leading edge side to the blade trailing edge side. Part 29
The flow channel structure is configured to change its direction on the trailing edge side, extend the turbine blade trailing edge portion of the blade effective portion 21 in the inner diameter direction, and be guided to the blade root portion 24. The cooling medium M flows from the blade root portion 24 toward the blade tip portion 29 in the blade effective portion 21 at the blade leading edge portion,
At the trailing edge of the blade, the effective blade portion 21 is guided so as to flow from the blade tip portion 29 to the blade root portion (blade platform) 24. The inner cooling flow passage 46 constitutes a zigzag cooling flow passage in the inner region of the outer cooling flow passage 45, and cools the blade intermediate portion between the leading edge and the trailing edge of the turbine blade.

The inner cooling flow path 46 extends outward in the longitudinal direction (outer diameter direction) of the blade effective portion 21 of the turbine blade, and is inverted 180 degrees inside the outer cooling flow path 45 on the blade tip portion 29 side. The flow channel structure is changed from the leading edge side of the blade to the trailing edge side of the blade in a zigzag manner while reversing the direction by 180 degrees between the blade root portion 24 and the blade tip portion 29 side of the blade effective portion 21. Is composed of. Finally, the inner cooling flow passage 46 is formed by the trailing edge side blade root portion (blade platform) 24 of the turbine blade.
And joins the outer cooling flow path 45 and communicates with the recovery passage 27.

Cooling of the closed-loop cooling type turbine rotor blade 20B is performed as follows.

During normal operation of the gas turbine, the cooling medium M is caused to flow into the supply passage 26, which is an introduction passage, from the bottom of the blade implantation portion 22, which is the blade root portion. This cooling medium M
Is branched at the blade effective portion inlet side of the turbine blade and is guided to the outer cooling passage 45 and the inner cooling passage 46.

The cooling medium M branched from the supply passage 26 for the cooling medium M and guided to the outer cooling flow passage 45 flows from the leading edge side of the blade effective portion 21 of the turbine blade to the blade tip portion 29 and the trailing edge side of the blade effective portion 21. While passing, the blade leading edge, blade leading edge, and blade trailing edge are effectively cooled from the inside.

Further, the cooling medium M guided from the supply passage 26 of the cooling medium M to the inner cooling flow passage 46 flows in the inner cooling flow passage 46 in a zigzag manner to counter-cool the blade middle portion, and then to the outer cooling flow. It merges with the cooling medium M from the passage 45 and is guided to the recovery passage 27, and the entire amount of the cooling medium M is recovered from the recovery passage 27 to the outside of the blade of the turbine blade.

In the turbine moving blade 20B, the cooling medium M is not blown out into the passage of the mainstream gas (combustion gas) from the blade effective portion 21 of the turbine blade, and the cooling medium M is guided to the closed loop structure to drive the turbine. The entire blade of blade 20B can be cooled. After that, a part of the cooling medium M guided to the turbine moving blade 20B is guided to the outer cooling flow passage 45 at the leading edge of the turbine blade, and the leading edge of the turbine blade from the blade root portion 24 to the blade tip portion 29 is first Can be cooled effectively. By using the cooling medium M that has not yet risen in temperature, the leading edge side of the blade effective portion 21 can be efficiently cooled. Also for the trailing edge of the turbine blade, the outer cooling flow path 45 passing through the blade leading edge and the blade tip does not form a zigzag-shaped flow path, and the flow path length is short and the heat exchange area is small.
The temperature rise of the cooling medium M is not so large that a sufficient cooling effect can be expected.

In the turbine rotor blade 20B shown in FIG. 8, the supply passage 26 is provided on the leading edge side of the blade implanting portion 22 of the turbine blade.
Although the example in which the recovery passage 27 is formed on the trailing edge side is shown, it may be reversed. That is, the trailing edge side of the blade-implanted portion 22 is used as a supply passage, and the cooling medium M guided in this supply passage has a flow opposite to that of the turbine moving blade 20B shown in FIG. You may make it collect | recover.

Also in this case, the entire blade of the turbine blade can be cooled by adopting the closed loop structure without blowing the cooling medium M into the passage of the mainstream gas (combustion gas), and further, the blade trailing edge portion and the blade tip portion. Not only that, the blade leading edge can be effectively and uniformly cooled over the entire blade surface.

[Fourth Embodiment] FIG. 9 is a vertical cross-sectional view showing a fourth embodiment of a closed-loop cooling type turbine rotor blade according to the present invention, and FIG. 10 is a vertical cross-sectional view taken along line XX of FIG. , Fig. 11
12 is a cross-sectional view (plan view) taken along line XI-XI in FIG.
FIG. 10 is a transverse sectional view taken along line XII-XII in FIG. 9.

The turbine rotor blade 20 shown in this embodiment
Since the overall configuration of C is substantially the same as that of the turbine rotor blade 20 shown in FIG. 1, the corresponding parts are designated by the same reference numerals and the description thereof will be omitted.

The turbine rotor blade 20C shown in FIG. 9 has two passages 2 in the blade-implanted portion 22 of the turbine blade in order to form the blade cooling flow passage 25 of the cooling medium M inside the turbine blade.
6, 27 are juxtaposed so as to extend in the longitudinal direction. One of the passages is a supply passage 26 for the cooling medium M, and the other passage is a recovery passage 27 for the cooling medium M. The supply passage 26 and the recovery passage 27 for the cooling medium M communicate with two cavities 48, 49 formed in the blade platform (blade root portion) 24 of the turbine blade or the blade shank portion 23, respectively.

As shown in FIG. 11, one of the cavities 48 and 49 is a blade back side cavity 48 including the leading edge portion of the turbine blade, and the other cavity is a blade vent side cavity 49 including the turbine blade trailing edge portion. Is. Two cavities 48,
As shown in FIG. 11, 49 is divided into a blade side and a blade back side of the turbine blade.

A plurality of cooling holes 50, for example, seven cooling holes 50 extending in the longitudinal direction (outer diameter direction) of the blade effective portion 21 of the turbine blade from the blade back side cavity 48 are arranged in a row, and the blade back side is formed of a cooling hole row. By forming the cooling flow passage 51 and flowing the cooling medium M through the blade back side cooling passage 51, the turbine rotor blade 20
C cools the blade back side from the front edge of the blade effective portion 21 toward the trailing edge. The blade back side cooling flow path 51 extends in the turbine blade longitudinal direction and communicates with one tip cavity 38 at the blade tip portion 29.

The tip cavity 38 is formed in the blade tip portion 29 of the turbine blade, and the cooling medium M flowing through the blade back side cooling flow path 51 in the tip cavity 38 changes its flow direction by 180 degrees and is inverted. It is guided to the wing ventral side cooling channel 52. The blade ventral side cooling flow channel 52 is located on the blade surface ventral side of the turbine blade,
For example, seven cooling holes 5 extending in the longitudinal direction of the blade effective portion 21.
3 are formed in rows and communicate with the blade ventral cavity 49 at the blade root portion 24. The blade ventral cavity 49 communicates with the recovery passage 27 for the cooling medium M.

As shown in FIG. 12, the blade back side cooling passages 51 and the blade vent side cooling passages 52 formed in the blade effective portion 21 of the turbine rotor blade 20C are formed by a plurality of cooling holes 50 and 53, respectively. An array of cooling holes is formed along the blade surface. A turbulent flow promoting rib 35 is formed on at least the inner wall of each cooling hole row facing the outer surface of the blade, and the turbulent flow promoting rib 35 disturbs the flow of the cooling medium M to enhance the cooling effect.

Further, the blade back side cooling passage 51 and the blade side cooling passage 52 are located at the outlet side of the cooling holes 50 and 53, respectively.
4, 55 are formed, and the flow passage narrowing portions 54, 55 reduce the flow passage area of the cooling hole row to reduce the flow passage area while increasing the flow velocity.
The flow rate of the cooling medium M can be adjusted for each cooling hole 50, 53. In order to secure a sufficient flow rate of the cooling medium M, the turbulent flow promoting rib does not necessarily have to be provided in the blade leading edge side cooling hole 50 of the blade back side cooling flow path 51. When the turbulent flow promoting ribs are not provided, the cooling efficiency is improved by increasing the flow rate of the cooling medium M at the blade leading edge portion.

Cooling of the closed loop cooling type turbine rotor blade 20C shown in FIG. 9 is performed as follows.

During normal operation of the gas turbine, the cooling medium M is caused to flow into the supply passage 26 from the bottom of the blade implanting portion 22. The cooling medium M is guided from the supply passage 26 to the blade back side cavity 48 formed in the blade root portion 24, and from the blade back side cavity 48 to each cooling hole 50 forming the blade back side cooling flow path 51. .

In the blade back side cooling flow passage 51 formed in the blade effective portion 21 of the turbine blade, the cooling medium M, which has not yet risen in temperature, is first guided and flowed to the blade leading edge and the blade back side. Thus, the leading edge of the blade and the back side of the blade are convectively cooled from the inside. At this time, the flow of the cooling medium M is disturbed by the rib effect of the turbulent flow promoting ribs 35 to make the temperature uniform, the cooling effect is increased, and the convection cooling effect is increased.

The tip cavity 3 at the blade tip of the turbine blade
The cooling medium M, which has flowed into 8 and has been merged, has a direction of 18
The turbulent flow promoting rib 35 increases convection cooling while increasing the cooling effect while being guided to the blade belly side cooling flow channel 52 by 0 degree and flowing in the cooling hole row of the blade belly side cooling flow channel 52 in the inner diameter direction. The blade is guided to the blade cavity 49 formed in the blade root portion 24. The cooling medium M is guided from the ventral cavity 49 to the recovery passage 27, and finally the entire amount is taken out of the blade of the turbine blade through the recovery passage 27.

In this turbine rotor blade 20C, the cooling medium M for cooling the blade effective portion 21 of the turbine blade does not blow out from the blade effective portion 21 or the blade tip portion 29 into the passage of the mainstream gas (combustion gas). The entire blade of the turbine blade can be cooled by the blade cooling flow path 25 having the closed loop structure.

Moreover, in this turbine rotor blade 20C, the cooling passages 51 and 5 are provided independently on the blade back side and blade back side of the turbine blade.
The cooling medium M that has not risen in temperature can be first supplied to the blade back side and the blade leading edge side of the turbine blade that can be cooled by 2 and has a high heat transfer coefficient on the blade surface, and the blade back side is cooled to the blade ventral side. Can be relatively strengthened. Furthermore, the blade back side and the blade ventral side cooling flow path 5
By providing a plurality of turbulent flow promoting ribs 35 in each of the cooling holes 50 and 53 of 1, 52, it is possible to increase the heat transfer coefficient of the blade surface facing the blade outer surface of the turbine blade. Conversely speaking, it becomes possible to reduce the flow rate of the cooling medium M. Moreover, when the turbulent flow promoting ribs 35 are not provided on the inner side surfaces of the cooling channels 51, 52, the increase in the pressure loss of the cooling medium M can be suppressed to the minimum. Further, the flow passage restricting portions 54 and 55 are provided for the respective cooling flow passages 51 and 52 so that the flow rate of the cooling medium M can be adjusted in accordance with the heat transfer coefficient of the opposing blade surfaces, so that the metal temperature can be made more uniform. Can be planned.

In this turbine moving blade 20C, the back cavity 48 includes the leading edge of the turbine blade, and the ventral cavity 49 includes the trailing edge of the turbine blade. It is also possible to include the trailing edge of the turbine blade and to include the leading edge of the turbine blade in the cavity on the ventral side of the blade. In this case, the cooling of the blade back side and the trailing edge side is relatively strengthened. .

Further, the supply passage 2 is provided in the cavity 49 on the ventral side of the blade.
6 may be connected and the recovery passage 27 may be connected to the blade back cavity 48.

[0096]

As described above, in the closed-loop cooling type turbine rotor blade according to the present invention, the cooling medium is effectively applied to the leading edge portion and the trailing edge portion of the turbine blade which is structurally difficult to cool. It can be supplied, the cooling effect is improved, the metal temperature of the turbine blade can be made more uniform, and the reliability is improved.
The consumption of the cooling medium can be reduced. In addition, since this closed-loop cooling turbine blade can be effectively cooled by the closed-loop cooling structure, the thermal efficiency of the gas turbine using this turbine blade will be greatly improved and it will be possible to cope with future high temperature of the gas turbine. Become.

By configuring the closed-loop cooling type turbine rotor blade according to the present invention as set forth in claim 1, the entire amount of the cooling medium after cooling the turbine blade is recovered from the recovery passage of the blade implanting portion to the outside of the blade. Since the cooling medium is not blown into the mainstream gas (combustion gas), the temperature decrease of the combustion gas can be avoided, while the turbine blade can be cooled with the closed loop cooling flow path structure. In the case of a combined cycle plant, part of the steam generated in the exhaust heat recovery boiler can be used as a cooling medium, and the steam after cooling the turbine rotor blades can be recovered by the steam turbine to improve the thermal efficiency of the plant. You can

With the closed-loop cooling type turbine rotor blade according to the present invention, by adopting the structure described in claim 2, the supply passage and the recovery passage for the cooling medium can be selected according to the design conditions of the gas turbine, and the turbine rotor The degree of freedom of the passage configuration formed in the blade can be selected.

Further, the closed-loop cooling turbine blade according to the present invention has the structure described in claim 3,
Since the cooling medium supplied to the inside of the blade of the turbine blade is supplied to the leading edge and the trailing edge of the blade effective part, the cooling medium that does not raise the temperature at the leading edge and the trailing edge of the blade effective part is used. It can be cooled positively and effectively.

Further, the closed-loop cooling type turbine rotor blade according to the present invention has the structure described in claim 4, whereby the cooling medium which has not risen in temperature is connected in parallel to the leading edge portion and the trailing edge portion of the turbine blade. The leading edge side and the trailing edge side of the turbine blade having a large heat transfer coefficient on the mainstream gas side can be effectively and efficiently cooled.

Further, the closed-loop cooling turbine blade according to the present invention has the structure described in claim 5,
It is possible to effectively cool the leading and trailing edges of turbine blades that are difficult to cool, and to uniformly cool the entire effective blade section, and to collect the branched cooling medium from one location. It will be possible.

On the other hand, the closed-loop cooling type turbine rotor blade according to the present invention has the structure according to the sixth aspect, whereby the front-side cooling passage and the rear-side cooling passage of the turbine blade are joined to each other. With the guide wall provided, it is possible to avoid the merging in which the flows of the cooling medium oppose each other, and it is possible to reduce the merging loss.

On the other hand, the closed-loop cooling type turbine rotor blade according to the present invention has the structure described in claim 7 to effectively cool the front and rear edges of the turbine blade, which is difficult to cool. As a result, the entire blade effective portion can be uniformly cooled, and the branched cooling medium can be collected from one place.

Further, the closed-loop cooling type turbine rotor blade according to the present invention has the structure described in claim 8, whereby the front cooling side and the rear cooling side of the turbine cooling blade are zigzag-shaped inside cooling flow in the outside cooling flow passage. It is possible to efficiently cool the central area of the blade between the leading edge and the trailing edge of the turbine blade in the passage, and the cooling medium can be supplied from the bottom of the blade implantation part, and the entire cooling medium after cooling can be recovered. Further, the cooling medium whose temperature has not risen can be supplied to the leading edge portion or the trailing edge portion of the turbine blade to effectively cool the blade leading edge portion, the blade tip portion and the blade trailing edge portion.

With the closed-loop cooling type turbine rotor blade according to the present invention, by constructing according to claim 9, the blade back side and blade vent side of the turbine blade can be cooled by independent cooling flow paths, It is possible to supply the cooling medium whose temperature has not risen to one of the dorsal side and the ventral side that is desired to enhance cooling.

Further, the closed-loop cooling type turbine rotor blade according to the present invention has the structure described in claim 10, thereby increasing the heat transfer coefficient of the cooling side surface facing the blade surface of the blade effective portion of the turbine blade. Therefore, the flow rate of the cooling medium can be reduced. Moreover, when the turbulent flow promoting ribs are not provided on the other surface, the increase in pressure loss of the cooling medium can be suppressed to the minimum.

Furthermore, the closed-loop cooling type turbine rotor blade according to the present invention has the structure described in claim 11, so that the plurality of cooling channels formed in the blade effective portion are provided for each cooling channel. The flow rate of the cooling medium can be adjusted according to the heat transfer coefficient of the opposing blade surfaces, and the metal temperature can be made more uniform.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a first embodiment of a closed-loop cooling type turbine rotor blade according to the present invention.

FIG. 2 is a cross-sectional view taken along the line II-II in FIG.

FIG. 3 is a vertical sectional view taken along the line III-III in FIG.

FIG. 4 is a vertical cross-sectional view showing a modified example of the first embodiment of the closed-loop cooled turbine blade according to the present invention.

FIG. 5 is a vertical cross-sectional view showing a second embodiment of a closed-loop cooled turbine blade according to the present invention.

6 is a cross-sectional view taken along the line VI-VI of FIG.

7 is a cross-sectional view taken along the line VII-VII of FIG.

FIG. 8 is a vertical cross-sectional view showing a third embodiment of a closed-loop cooled turbine blade according to the present invention.

FIG. 9 is a vertical sectional view showing a fourth embodiment of a closed-loop cooling type turbine rotor blade according to the present invention.

10 is a partial vertical cross-sectional view taken along the line XX of FIG.

11 is a cross-sectional view taken along the line XI-XI of FIG.

12 is a cross-sectional view taken along line XII-XII in FIG.

FIG. 13 is a partial cross-sectional view showing a general gas turbine.

FIG. 14 is a vertical cross-sectional view of a turbine rotor blade applied to a conventional gas turbine.

FIG. 15A is a diagram showing a pressure drop of a cooling medium at a trailing edge portion of a turbine blade, and FIG. 15B is a diagram showing a temperature rise of the cooling medium at a trailing edge portion of the turbine blade.

FIG. 16 is a diagram showing a mainstream gas heat transfer coefficient distribution on the outer surface of a turbine blade.

[Explanation of symbols]

 20 Turbine Blade 21 Effective Blade Section 22 Blade Implantation Section 23 Shank Section 24 Blade Platform (Blade Root) 25 Blade Cooling Flow Path 26 Supply Passage 26a Front Supply Passage 26b Rear Supply Passage 27 Recovery Passage 28 Leading Edge Passage 29 Blade tip part (blade tip portion) 30 Return channel 31 Trailing edge channel 33 Front side cooling channel 34 Rear side cooling channel 35 Turbulent flow promoting ribs 37a, 37b, 37c Cavity 38 Tip cavity 39 Blade cooling channel 39a, 39b , 39c Cooling holes 39A, 39B, 39C Cooling hole row (cooling flow path) 40, 41 Flow path narrowing part 45 Outer cooling flow path 46 Inner cooling flow path 48 Blade back cavity 49 Blade belly cavity 50, 53 Cooling hole 51 Blade back side cooling channel 52 Blade ventilating side cooling channel

Claims (11)

[Claims] 1. A turbine for cooling the inside of a turbine blade by hollowing the inside of the blade to form a blade cooling flow path, and supplying a cooling medium from the bottom of the blade implantation portion to a blade cooling flow path through a supply passage. In the moving blade, a recovery passage that can collect the cooling medium from the blade cooling passage to the outside of the turbine blade is provided in the blade implantation portion independently of the supply passage, and the entire cooling medium after cooling the turbine blade is collected in the collection passage. A closed-loop cooled turbine blade characterized by being configured as described above. 2. A cooling medium supply passage formed in a blade-implanted portion of a turbine blade is provided on either one of a leading edge side and a trailing edge side of the turbine blade, and a cooling medium recovery passage is independently provided on the other side. The closed-loop cooled turbine blade according to claim 1. 3. The blade cooling flow passage formed inside the blade of a turbine blade is formed in a flow passage structure capable of supplying the cooling medium from the supply passage to the leading edge portion and the trailing edge portion of the blade effective portion first. The closed-loop cooled turbine blade according to claim 1. 4. A supply passage formed in a blade implantation portion of a turbine blade is branched into a front supply passage and a rear supply passage at a blade shank portion, and one of the branched supply passages is recovered at a blade shank portion. The closed-loop cooled turbine blade according to any one of claims 1 to 3, which intersects with a passage. 5. A blade cooling flow passage formed in a blade effective portion of a turbine blade includes a front cooling flow passage and a rear cooling flow passage, the front cooling flow passage communicating with a front supply passage of a blade shank portion. Then, the blade effective portion on the leading edge side of the turbine blade flows in the outer diameter direction, and the flow direction is reversed at the blade tip portion to form a flow passage structure that faces the inner diameter direction, while the rear side cooling passage forms the blade shank portion. A flow passage structure is formed that communicates with the rear supply passage and flows in the outer diameter direction in the blade effective portion on the trailing edge side of the turbine blade, and reverses the flow direction at the blade tip portion to face the inner diameter direction. 5. The closed-loop cooling turbine blade according to claim 4, wherein the front cooling passage and the rear cooling passage are joined to a return passage formed near the blade center between the blade and the trailing edge and communicated with the recovery passage. . 6. A return passage formed near a blade central portion between a leading edge and a trailing edge of a turbine blade forms a merging portion on an inlet side formed in a blade tip portion, and a cooling medium of a cooling medium is formed at this merging portion. The closed-loop cooled turbine blade according to claim 5, further comprising a guide wall that guides the flow in the inner diameter direction. 7. The turbine blade forms a blade leading edge cavity, a central cavity, and a blade trailing edge side cavity in a blade platform and a tip cavity in a blade tip portion, while a cooling medium supply passage is branched. The central cavity communicates with the cooling medium recovery passage, and communicates with the blade leading edge side cavity and the blade trailing edge side cavity. The closed-loop cooled turbine blade according to claim 4, wherein the cooling passage extends and communicates with the tip cavity of the blade tip portion. 8. A blade cooling passage of a turbine blade is branched into an outer cooling passage and an inner cooling passage at a blade shank portion, while the outer cooling passage has a leading edge portion of the blade effective portion as a blade tip portion. After extending toward the wing shank, the wing tip changes its direction and extends from the wing leading edge to the wing trailing edge, and then changes at the wing tip trailing edge to change the wing effective portion trailing edge toward the wing shank. In addition, the inner cooling flow path is configured to have a zigzag shape that flows inside the outer cooling flow path, and the outer cooling flow path and the inner cooling flow path merge at the blade shank portion to collect the recovery path. The closed-loop cooled turbine blade according to claim 1, which is communicated with the turbine blade. 9. A turbine blade has a blade backside cavity and a blade ventral side cavity in a blade platform, one of the blade backside and the blade ventral side cavity is connected to a cooling medium supply passage, and the other cavity is cooled. While communicating the medium recovery passage, the blade back side cooling passage and the blade back side cooling passage are formed along the blade surface of the blade effective portion from the blade back side and the blade side cavity to form in the blade tip portion. The closed-loop cooled turbine blade according to claim 1, wherein the closed-loop cooled turbine blade is communicated with a tip cavity. 10. A plurality of cooling channels arranged along the blade surface of a blade effective portion of a turbine blade, wherein a turbulent flow promoting rib for a cooling medium is provided on an inner wall of the blade effective portion on the blade surface side. 7 or 9
The closed-loop cooled turbine blade described in. 11. A plurality of cooling flow passages of a blade effective portion that communicates a cavity formed in a blade platform of a turbine blade and a tip cavity formed in a blade tip portion are provided with a flow passage inlet portion and a flow passage outlet portion. The closed-loop cooling type turbine rotor blade according to claim 7 or 9, wherein a flow passage throttle portion is provided on at least one of the above.