JPH09250361A - Gas turbine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve mixing performance of liquid fuel and air so as to reduce the rate of NOx by arranging the falling down part of liquid fuel between the bending part of the upper end of a combustor main body and pre-mixture chamber, and discharging air led from a cooling air hole drilled on the vertical wall surface of the combustor main body, to the lower end part of the falling down part. SOLUTION: In the combustor of a gas turbine, a combustor main body 2 formed in a vertical cylinder shape is arranged in an outer cylinder 1, a liner 3 is fitted to the center part thereof from an upper part, and an auxiliary fuel injection nozzle 5 for injecting fuel only at the time of ignition is arranged on the lower end part of the liner 3 by being existent in a combustion chamber B. In this case, the inner rim of the upper end part 2a of the combustor main body 2 is extended in a vertical direction till the inlet part of a pre-mixture chamber A arranged on the inner side of a short diameter part 2b so as to form a falling down part C, and a cooling air hole H drilled on the short diameter part 2b is arranged on the horizontal direction outer side of the falling down surface C forming part of the upper end part 2a. It is thus possible to splash away liquid fuel dropped down from the lower end of the falling down surface C by air led from the cooling air hole H so as to carry out mixing sufficiently.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas turbine, and more particularly to an improved structure of a gas passage portion leading to a compressor, a combustor, and a rotor blade for improving the output characteristics thereof.

[0002]

2. Description of the Related Art A gas turbine is greatly affected in its output and efficiency by the pressure, temperature, and coolability of a gas passage portion reaching a compressor, a combustor, and a moving blade. Hereinafter, the configuration of each part in the conventional gas turbine will be described. First, the combustor, conventionally, a structure of providing a premixing chamber for the low NO _X reduction, real-Open No. 5-96759
It is known in Japanese Patent Application Publication No. JP-A-2003-115, in which the liquid fuel sprayed from the liquid fuel injection nozzle is prevented from flowing along the inner wall surface of the combustor and is again fed into the space of the premixing chamber. A structure in which a diaphragm member for discharging is arranged is also disclosed. This structure will be described with reference to the side sectional view of the conventional combustor shown in FIG. In the combustor, a combustor main body 2 which is a vertical cylindrical body is arranged in an outer cylinder 1, and a liner 3 is fitted and arranged from above in a central portion of the combustor main body 2. A fuel passage and an air passage are bored in the liner 3, and a sub-fuel injection nozzle 5 that faces the combustion chamber B described later and injects fuel only at the time of ignition is arranged at a lower end portion thereof. There is.

The upper end 2a 'of the combustor body 2 is bent in the horizontal direction to form a thrower T on the outer edge of the combustor body 2 for sucking the air in the outer cylinder 1 into the combustor body 2. Has become. A liquid fuel injection nozzle 4 is disposed near the inside of the thrower T, and the space between the outer surface of the liner 3 and the inner surface of the minor diameter portion 2b of the fuel device body 2 is filled with air introduced from the thrower T. And a premixing chamber A for mixing the fuel sprayed from the liquid fuel injection nozzle 4 with each other. In the combustor body 2, the electrode 7 of the spark plug P is made to face the interior of the long diameter portion 2c below the premixing chamber A where the liner 3 does not exist to form a combustion chamber B. Then, slightly below the bent portion between the upper end portion 2a ′ of the combustor body 2 and the short diameter portion 2b, the diaphragm plate member 10 is horizontally extended from the inner wall surface of the short diameter portion 2b.
And the liquid fuel accumulated on the throttle plate member 10 is scattered into the space of the premix chamber A by the flow of air introduced from the thrower T.

Further, as shown in FIG. 16 and FIG. 17 which is a side sectional view showing a conventional spark plug mounting structure, the spark plug P is from the outer cylinder 1 of the combustor to the combustion chamber B of the combustor body 2. It is laid all over the part. The spark plug P has a terminal Pa at the outer end, and an electrode 7 protrudes from the body 6 from the inner end so that the electrode 6 faces the combustion chamber B in the combustor body 2. There is. The body 6 at the inner end is
It is fixed to the combustor body 2 via a spark plug receiver 9 '. An insulator 8 is provided around the electrode 7 in the body 6.

Conventionally, in a gas turbine, since hot air that has been burned and expanded is used, a cooling air flow passage is provided at an appropriate location. Among them, in the combustor, in order to introduce the air in the outer cylinder 1 into the combustor body 2, a slit-shaped cooling air hole H is formed at an appropriate position on the wall surface of the combustor body 2. ing. In the spark plug P, the outer cylinder 1 is attached to the body 6 at the inner end (electrode side).
A cooling air hole 6a is provided in a penetrating manner inside and outside the inside of the combustor body 2 so that the air in the outer cylinder 1 enters the body 6 and suppresses abnormal heating of the electrode 7.

The high temperature air burned through the combustor is supplied to the turbine section through the turbine intake duct. Conventionally, the scroll itself forming the turbine intake duct is a single plate and has a cooling structure. If not, or if it is provided, a structure in which the entire scroll is a double wall, a structure in which a double wall is partially provided and air is blown between them to cool it, and in addition to this structure, It is known that a structure in which the air remaining after the spray cooling is made to flow out in a film form to cool one wall portion of the scroll is adopted.

Next, in the turbine section, stationary stationary blades and moving blades are alternately arranged. The stationary blade (turbine nozzle) support structure has an outer end portion of the stationary blade formed into an annular stationary blade. It is fixed to a blade supporting member (turbine nozzle support), and these stationary blade supporting members are fixed inside an integral tubular stationary blade supporting member housing (turbine nozzle support housing). Among them, as a method for fixing the stationary blade to the stationary blade supporting member, a method is known in which a fitting groove is provided in the stationary blade supporting member and a fitting portion formed at the outer end portion of the stationary blade is fitted therein. Has become.

Further, as a structure for attaching the turbine blade to the disc, as shown in FIG. 18, the fitting portion of the shank portion 17'b of the rotor blade 17 ', which is the attachment portion to the disc, is fitted to the disc. The 17'c has a plurality of steps for positioning, and the fitting hole provided on the outer circumference of the disk is also shaped to fit in this step, but this is complicated, JP-A-4-23780 discloses that the fitting portion has a simple dovetail shape and the fitting hole of the disk has a shape matching this for the sake of simplicity and cost reduction.
It is publicly known in Japanese Patent No.

With respect to the moving blade, a conventional cooling air passage structure will be described with reference to FIGS. 18 to 21. FIG. 18 (a) is a perspective view of a conventional blade having a fitting portion having a plurality of fitting step portions at the tip of the shank portion, in which cooling air is introduced from the side of the shank portion, Similarly, (b) is a perspective view of a type in which cooling air is introduced from the side and the tip of the shank portion, and (c) is (b).
FIG. 19 is a perspective sectional view of the illustrated moving blade, FIG. 19 is a side sectional view of a structure for introducing air to the side of the moving blade shank from a cooling air passage formed along a duct fixed to the stationary blade, and FIG. FIG. 21 is a side sectional view of a structure in which a cooling air hole communicating with the fitting hole of the blade is formed. FIG. 21 is a side view of a structure in which a cooling air passage communicating with the fitting hole of the moving blade is formed between the disk and the seal member. FIG.

Conventionally, as shown in FIG. 18, a shank portion 17 'is provided.
In the moving blade 17 'in which the fitting portion 17'c at the base end of b has a plurality of conventional stepped portions, as shown in (c), from the shank portion 17'b to the moving blade 17'. , Cooling air holes h'or h "are provided. (C) The moving blade 17 'shown in the drawing is the same as the moving blade 17' shown in (b), and the cooling air hole h'is provided therein. Although “and h” are formed, only the cooling air hole h ′ is formed in the moving blade 17 ′ shown in FIG. The opening position of each cooling air hole is the shank portion 17'b for the cooling air hole h '.
Is located at the X position of the side position (the bottom position of the rib portion 17'a) of the fitting portion 17'c for the cooling air hole h ".
Is at the Y position which is the tip of the.

As a conventional air passage structure to this opening, as shown in FIG. 19, a cooling air passage 24 is formed along a duct 23 integrally fixed to the stationary blade 16, as shown in FIG.
As in 0, in the disk 18 ', the air chamber E'provided to the side of the disk 17' and the fitting portion 17'c of the moving blade 17 '
The cooling air hole 18'b communicating with the fitting hole 18'a for fitting the
As described above, the disc 18 'is covered with a disc-shaped seal member 20' that rotates integrally with the disc 18 ', and the gap between the seal member 20' and the disc 18 'is fitted as a cooling air passage. There is a structure for communicating with the joint hole 18'a. The configuration of FIG. 19 is the shank portion 1 in FIGS. 18 (a) to 18 (c).
In the openings of the cooling air holes h ′ provided at the X position on the side of 7′b, the configurations of FIGS.
This is effective as a configuration for introducing air into the opening of the cooling air hole h ″ provided at the tip Y position of the fitting portion 17′c shown in the figure.

As the compressor, a multi-stage centrifugal type is known as shown in FIG. The conventional multistage centrifugal compressor shown in FIG. 22 has an intake duct 12'a and an impeller 1.
Front stage compressor 1 consisting of 2'b and diffuser 12'c
2'and the impeller 12'a and diffuser 14'c are connected by an interstage duct 13. Among them, the inter-stage duct 13 'is an S-shaped crossover duct, and an S-shaped inlet guide vane 13'a is formed at the upper end, and the duct portion 1 in the vertical direction is formed below it.
3'b is formed and is interposed between the diffuser 12'c in the front stage and the impeller 14'a in the rear stage.

[0013]

First, the problems relating to the conventional combustor will be described. The premixing chamber A is provided for completely spraying the liquid fuel LO sprayed from the liquid fuel injection nozzle 4 into the air to mix it and sending it to the combustion chamber B in order to reduce the NO _x . The conventional diaphragm plate member 10 shown in FIG. 16 is provided to prevent the liquid fuel LO from directly flowing down into the combustion chamber B along the inner wall surface of the combustor body 2. Although effective in this regard, on the other hand, in the space below the diaphragm plate material 10, the vortex flow S of the air is generated.
Occurs, and the swirl flow S promotes the invasion of the flame from the combustion chamber B into the premixing chamber A, which lowers the combustion efficiency. As for the method of scattering the liquid fuel propagating along the wall surface into the space of the premixing chamber A, it is conceivable to extend the vertical length of the minor diameter portion 2b, but this has a structural limitation of the combustor. . The cooling air holes H bored in the combustor body 2 are conventionally bored at arbitrary positions, and the function of returning the liquid fuel propagating along the inner wall surface of the combustor body 2 into the premixing chamber A is considered. Not not. Further, the turbine intake vent that guides the high temperature combustion gas toward the turbine portion is apt to undergo thermal deformation (thermal distortion), but its cooling function is not considered.

Further, as for the spark plug P, conventionally, FIG.
As shown in FIG. 3, the opening area of the cooling air hole 6a to the inner space of the outer cylinder 1 is large, and the dust contained in the air in the outer cylinder 1 is discharged from the body inside the body 6 through the cooling air hole 6a. 6 Air gap A formed in the gap between the inner surface of insulator 6 and the outer surface of insulator 8
If the dust is larger than the air gap AG, it will be clogged and cause ignition failure.

Next, in the conventional structure of the turbine intake duct, first, in the case where the turbine intake duct is formed of a single plate and does not have a cooling structure, as described in the above-mentioned combustor, low NO _{x is used.} If the thermal efficiency is increased by increasing the efficiency, the air flowing in the turbine intake duct will also have high temperature and pressure,
Creep deformation may occur in the scroll that constitutes the turbine intake duct. With respect to the structure provided with the cooling structure, in the structure having the double wall as a whole, and in the structure having the air blowing hole in the double wall portion, the cooling effect can be achieved by the body, but a large amount of cooling air is required. Since this cooling air is taken in from the compressor, if this amount is large, it leads to the loss of the original air pressure for driving the turbine.

In the structure in which the air blowing holes are provided in the double wall portion and the film cooling portion is formed, the cooling effect can be obtained with a small amount of air, so that the air pressure loss amount in the compressor can be suppressed to a low level, which is the most desirable. It is a thing. However, in this conventional structure, the inner wall of the double wall portion has a high temperature and the outer wall has a lower temperature than that. Due to this temperature difference, a compressive stress is applied to the inner wall and a tensile stress is applied to the outer wall. As a result, the inner wall bends toward the outer wall,
The accurate cooling effect cannot be obtained.

Next, regarding the mounting structure of the stationary blades in the turbine section, since high-temperature air circulates in the stationary blades, conventionally there is a structure in which the stationary blades are composed of members having high temperature strength. However, since a low-cost low-strength material is used for the vane support member that supports this, for example, in the case of the one having the fixing structure that fits in the fitting groove as described above, the air of extremely high temperature is used. When flows into the stationary blade, bending stress is also applied to the stationary blade support member, causing thermal deformation.

As for the moving blade, first, for facilitating the working, it is desirable that the fitting portion at the base end of the shank portion has a dovetail shape, as disclosed in Japanese Patent Laid-Open No. 4-237802. On the other hand, as the passage structure of the cooling air, the one shown in FIG. 19 is the duct 2 fixedly provided.
3 requires a seal structure for the rotating moving blade 17 'and the disk 18', which may cause air leakage, and in order to avoid this, the seal structure tends to be complicated. Further, the disk 1 shown in FIG. 20 has a strong stress.
To form such cooling air holes 18'b in 8'is
It is disadvantageous in terms of strength.

In the structure shown in FIG. 21, since the seal member 20 'is integral with the disc 18', the sealing property of the cooling air passage D'between the seal member 20 'and the disc 18' is excellent. Is the shank portion 1 as shown in FIG.
Fitting portion 17'c in which the base end portion of 7'b has a plurality of steps
Is assumed. In other words, by having such a stepped portion, the fitting portion 17'c can be securely attached to the disc 1
When positioned in the 8'fitting hole 18'a,
Even if an air reservoir communicating with the opening of the cooling air hole h ″ provided at the tip Y position of the fitting portion 17′c is formed in the fitting hole 18′a, the inside of the fitting hole 18′a is also formed. Fitting part 1 fitted to
The 7'c does not wobble. However, in the case where the fitting portion at the shank base end to the fitting hole on the outer circumference of the disc is formed into a dovetail shape, the fitting hole is fitted to the fitting hole in order to secure such an air pool. If a gap is provided between the dovetail-shaped fitting portion and the fitting portion, the fitting portion wobbles in the fitting hole, and the rotor blade cannot be positioned in the disk radial direction.

Finally, the problem of pressure loss in the conventional compressor will be described. In the conventional multi-stage centrifugal compressor as described above, there is a problem that the inter-stage duct 13 '(crossover duct) has a complicated shape and is costly.
And, there is a problem that a slight pressure loss occurs in relation to the internal structure. That is, the diffuser 1 in the front stage
The air discharged from 2'c has a relatively high speed and tends to swirl. This air changes its direction by 180 ° due to the inter-stage duct 13 ', producing a high flow velocity portion and a low flow velocity portion, and the air is rectified at the high flow velocity portion, so only the rectification portion is supplied to the next stage impeller. To be done. That is, the air that flows into the part that is not rectified and has a slow flow velocity causes a pressure loss. As described above, the combustor is also provided with a configuration for achieving high temperature in order to achieve low NO _x , but high pressure is also an important factor, and pressure loss in the compressor causes Since it will lead to a decrease in the air pressure in the turbine section thereafter, it is desirable to keep the pressure loss in the compressor as low as possible.

[0021]

The present invention uses the following means in order to correct the above problems and provide a gas turbine with high output efficiency. First of all, in a combustor of a gas turbine, an upper end portion of a combustor body forming a vertical cylinder is bent horizontally outward to provide an air intake port, and a liquid is provided near the inside of the air intake port. In a configuration in which a fuel injection nozzle is arranged and a premixing chamber is provided between a liner vertically arranged in the center of the combustor body and a vertical wall surface of the combustor body, the upper end of the combustor body is bent. A sliding portion for the liquid fuel is provided from the portion toward the premixing chamber, and the lower end portion of the sliding portion is in contact with air introduced from a cooling air hole formed in the vertical wall surface of the combustor body.

Secondly, in the spark plug attached to the combustor of the gas turbine, the gap between the body covering the outer opening of the cooling air hole formed in the body of the spark plug and the body is the cooling air. The opening is smaller than the air gap of the spark plug.

Thirdly, in a turbine intake duct communicating from a combustor of a gas turbine to a turbine portion, a wall portion of the turbine intake duct is partially made into a double wall, and an air compression is applied to an outer wall of the double wall. A hole that communicates with the vessel is formed, and a blowing cooling unit that blows the air introduced from the hole onto the inner wall, a convection cooling unit of the double wall that follows the cooling unit, and a film shape from the convection cooling unit of the double wall. In a structure having a film cooling section for cooling the single wall portion by allowing air to flow out to the inner wall of the double wall convection cooling section near the film cooling section, a slit is provided on the inner wall of the convection cooling section. A pad is provided which secures a gap between the outer wall and the inner wall, which serves as an air communication passage from the cooling section to the film cooling section.

Fourthly, in a structure in which a stationary blade of a gas turbine is supported by an annular stationary blade supporting member, and the stationary blade supporting member is supported in a tubular stationary blade supporting member housing, the stationary blade supporting member is provided. In the housing, a through hole for introducing air is provided in a tangential direction of an outer circumference of the vane support member, while an air introduction path communicating from the compressor outlet to the outside of the vane support member housing is formed.

Fifthly, the shank portion of the moving blade of the gas turbine is fitted into the fitting hole formed on the outer circumference of the disk, and the fitting portion to be fitted into the fitting hole formed at the tip of the shank portion. In a dovetail shape, a cooling air hole is formed from the tip of the shank portion to the moving blade, and the cooling air hole is formed in the fitting hole between the shank portion and the fitting portion. While securing a gap serving as an air reservoir that communicates with the disk, a positioning projection that abuts on the tip of the fitting portion of the shank portion is projected from the disc.

Sixth, in the multistage centrifugal compressor of the gas turbine, the interstage passage is used as a volume expansion chamber.

[0027]

Embodiments of the present invention will be described with reference to the drawings. 1 is an overall side sectional view of a gas turbine, FIG. 2 is a side sectional view of a combustor according to the present invention, and FIG. 3 is a partial side sectional view showing a spark plug mounting structure according to an embodiment of the present invention. Is a side sectional view of a spark plug of another embodiment, FIG. 5 is a side sectional view showing a cooling structure of the turbine intake duct 15, and FIG. 6 is a slit S and a seat SP in the double wall portion of the scroll 15A. FIG. 7 is a partial enlarged side sectional view showing a cooling structure of the turbine intake duct 15, FIG. 8 is a side sectional view showing a cooling structure for the support mechanism of the stationary blades 16, and FIG. Z line sectional view, FIG.
0 is a partial side sectional view of the moving blade 17, FIG. 11 is a partial front view of the same, FIG. 12 is a partial front view showing fitting of the shank portion 16a of the moving blade 16 to the disk 17, and FIG. 13 is a shank of the moving blade 16. 1 is a side sectional view showing a cooling air hole h formed in the portion 16a, and FIG.
5 is a side sectional view showing an interstage passage structure in the multistage centrifugal compressor.

First, a schematic configuration of the entire gas turbine will be described with reference to FIG. A drive shaft 19 is supported in the center of the main body housing 12, and a pre-stage compressor 12, an interstage duct 13, and a post-stage compressor 14 are continuously provided around the drive shaft 19 from the left side in the drawing. Is provided with a compressor. The pre-stage compressor 12 includes the intake duct 12a and the drive shaft 1 from the air inlet side.
Impeller 12b and diffuser 1 that rotate together with 9
2 c are connected in series, and the latter-stage compressor 14 includes an impeller 14 a and a diffuser 14 b that rotate integrally with the drive shaft 19.
It will be connected in series. The inter-stage duct 13 will be described in detail later. The air discharged from the compressor (post-stage compressor 14) is sent into the combustor body 2 through the outer cylinder 1 containing the combustor, and the fuel is supplied and ignited in the combustor body 2. , And expands the air, and sends the expanded air from the turbine intake duct 15 to the turbine section. In the turbine section, the stationary blades 16A, 16B, 16C (collectively, the stationary blade 1
6) and rotor blades 17A, 17B, 17C (collectively rotor blade 1
With 7), a ventilation passage for the expanded air is formed, and the expanded air that has passed through the ventilation passage is discharged to the outside through the exhaust pipe 21. Rotating the moving blades 17 in the process of the expanded air passing through the ventilation passages of the turbine section, the moving blades 17A, 17B, 1
The discs 18A, 18B, and 18C (collectively discs 18) integrated with 7C are rotated, and the drive shaft 19 that is the same rotation shaft of all the discs 18 is rotationally driven.

The structure of the combustor will be described with reference to FIG. The schematic structure is the same as the conventional combustor structure shown in FIG. Among these, in the combustor shown in FIG. 2, the diaphragm plate material 10 shown in FIG.
And extends in the vertical direction up to the entrance portion of, and forms a sliding surface C. And, the short diameter portion 2b which has been arbitrarily positioned in the past
At least the upper end 2a.
The position is limited to the outer side in the horizontal direction of the portion where the sliding surface C is formed.

In such a structure, of the liquid fuel sprayed from the liquid fuel injection nozzle 4, the liquid fuel LO which has been conventionally accumulated on the diaphragm plate member 10 is the combustor body 2
The sliding surface C of the upper end portion 2a of the above will slide down.
Then, the air introduced into the combustor body 2 from the inside of the outer cylinder 1 through the cooling air holes H arranged outside the sliding surface C is located inside the lower end portion of the sliding surface C ( Liner 3)
The liquid fuel LO dripping from the lower end of the sliding surface C upon hitting the direction is scattered into the space of the premix chamber A. That is, similar to the diaphragm plate member 10, the liquid fuel was scattered into the space of the premixing chamber C without being dropped onto the combustion chamber B along the inner wall surface of the combustor body, and was sufficiently introduced from the thrower T. It has the effect of mixing with air.

Further, in the diaphragm plate member 10, there was a problem that an air vortex S was generated below the diaphragm plate member 10. However, in the configuration of FIG. 2, the sliding surface C of the upper end portion 2a is in the vertical direction, and the cooling air hole is formed. The air introduced from H also flows downward along the sliding surface C, so a vortex is hardly generated,
Even if it occurs, it will be extremely small.

Next, the spark plug P is provided so as to face the combustion chamber C in the combustor body 2 and extend from the outer cylinder 1 to the long diameter portion 2c of the combustor body 2. As described above, the outer end of the spark plug receiver 9 ′ for fixing the inner end portion of the spark plug P to the long diameter portion 2 c of the combustor body 2 is located inside the cooling air hole 6 a of the body 6 of the spark plug P. Therefore, the outer opening of the cooling air hole 6a was substantially exposed to the space inside the outer cylinder 1.

On the other hand, in the mounting structure of the spark plug P shown in FIG. 3, the outer end of the spark plug receiver 9 is extended outward in the horizontal direction (the outer cylinder 1 side) to form the step of the body 6. Thus, the outer end portion of the long diameter portion 6c, which has a longer diameter than the short diameter portion 6b for forming the cooling air hole 6a, is covered. As a result, the cooling air hole 6a is connected to the spark plug receiver 9
The air introduction portion from the outer cylinder 1 to the inside of the spark plug receiver 9 is formed by the inner surface of the spark plug receiver 9 and the long diameter portion 6 of the body 6.
It becomes a gap BG between the outer surface and a. That is, the air in the outer cylinder 1 is not introduced into the cooling air hole 6a unless it passes through the gap BG.

On the other hand, at the inner end of the spark plug P arranged inside the combustor body 2, an air gap AG is formed between the outer surface of the insulator 8 covering the electrode 7 and the inner surface of the body 6.
The gap BG is smaller than the air gap AG. In order for dust to enter the body 6, it must be large enough to pass through the gap BG. If the air gap AG, which is larger than the gap BG, can pass through the gap BG, dust can pass through the air gap AG. Therefore, the fact that the air gap AG is clogged with dust can be eliminated.

In the spark plug P shown in FIG. 4, the spark plug receiver 9 is attached in the process of mounting the spark plug P on the combustor body 2 as shown in FIG.
Instead of forming the gap BG at the spark plug P itself,
A small gap BG (smaller than the air gap AG) is formed in the air introduction portion for the cooling air hole 6a. First, the body 6 has the steps as described above, and the cylindrical portion 11 is extended from the major diameter portion 6c toward the minor diameter portion 6b to cover the cooling air hole 6a. A gap BG smaller than the air gap AG is formed between the inner surface of the tubular portion 11 and the outer surface of the short diameter portion 6b of the body 6.

The passage structure of the cooling air in the combustor and the spark plug P attached to the combustor is as described above.
Next, the cooling structure of the turbine intake duct 15 will be described with reference to FIGS. 5 to 7. The turbine intake duct 15
As shown in FIG. 5, it comprises a scroll 15A and a scroll 15B, and a cooling structure is provided for the scroll 15A. That is, the scroll 15A includes the wall members 15a, 15b, 1
5c and 15d are arranged in a continuous manner by partially superimposing them, and double wall portions and single wall portions are alternately provided in a continuous manner. For example, in the overlapping portion of the wall materials 15a and 15b, the wall material 15a is an inner wall and the wall 15b is an outer wall. A blow hole (impingement hole) IH is provided near the upper end of the overlapped portion, that is, the outer wall portion of the double wall portion (if the overlapped portion of the wall members 15a and 15b is the wall member 15a). Has been drilled. Scroll 1
The outside of 5A is a cooling air duct F for introducing cooling air from the outlet of the (post-stage) compressor 14 (on the upstream side of the combustor). It is introduced through the IH and sprayed on the inner wall.
As shown in FIG. 7, this portion is referred to as a blow cooling unit C1.

The cooling air blown to the inner wall in the blow cooling section C1 is used for the outer wall and the inner wall of the double wall portion (for example, the wall material 1).
5a and 15b) diffuses and causes convection to cool the double wall portion. This is the convection cooling section C2.
Further, the outer wall of the double wall (wall member 15b in the case of the double wall members 15a and 15b) is extended below the inner wall, and the lower wall member (for example, wall member 15c) is provided. It is a single wall until it polymerizes. In this part, between the double walls,
That is, air flows out like a film from the convection cooling section C2 to cool this single wall portion. This portion is referred to as a film cooling portion C3. In this way, the three cooling units are continuously provided to effectively cool the scroll 15A, that is, the wall material of the turbine intake duct 15 with a small amount of cooling air, and to cope with high temperature and high pressure. The turbine intake duct 15 can be provided.

However, the scroll 15 having such a structure
In A, the inner wall portion of the overlapped portion of the wall material is heated by the high-temperature high-pressure air flowing in the turbine intake duct 15, while the outer wall portion is the air before combustion in the cooling air duct F outside thereof. Since there is a high temperature difference, the inner wall may warp toward the outer wall. In order to avoid this, in this embodiment, as shown in FIGS. 6 and 7, slits are formed at the lower end of the inner wall portion (that is, the inner wall portion of the double wall convection cooling portion C2 near the film cooling portion C3). S is provided so that the stress applied to the inner wall is released. Also,
The end of the slit S is rounded to form an end hole Sa,
Concentration of stress in this portion is avoided.

Further, a pad (spacer) SP is provided at a portion of the outer wall facing the slit S,
Even if the inner wall warps toward the outer wall due to thermal deformation, the air flows from the convection cooling unit C2 to the film cooling unit C3 except for the portion where the seat SP abuts on the inner wall and the seat SP abuts. It will be secured.

Next, the cooling structure in the stationary blade supporting mechanism of the turbine section will be described with reference to FIGS. 8 and 9. Static wings 1
Each of 6B and 16C has a claw portion 16a projecting from its outer end and is locked to an annular stationary blade support member 24A or 24B (collectively, stationary blade support member 27). Member 2
Each of 4A and 24B is screwed to a mounting seat that projects radially from the inner surface of a tubular vane support member housing 25 that encloses the entire turbine portion. Further, the cover 26 is fastened together with bolts for screwing the stationary blade supporting members 24A and 24B, and the portion surrounded by the cover 26, the stationary blade supporting member 24, and the stationary blade supporting member housing 25 is a cooling air cavity. It is called CC. There is a small gap between the cover 26 and the inner surface of the stationary blade supporting member housing 25, and between the cooling air cavity CC and the outer surface of the stationary blade supporting member housing 25 and the stationary blade 16 / moving blade 17. Space I formed
Air can flow into. The stator vane support member housing 25 has a cooling air introduction hole 25a penetrating therethrough in the tangential direction of the annular stator vane support member 24, and its outlet communicates with the cooling air cavity CC.

Scroll 1 of the turbine intake duct 15
A cooling air duct G for introducing air from the outlet of the (post-stage) compressor 14 is formed outside 5B, and communicates with the outer surface of the stationary blade supporting member housing 25. Cooling air is introduced from the cooling air duct 25 into the cooling air cavity CC through the cooling air introducing hole 25a. The direction of the cooling air introducing hole 25a and the pressures inside and outside the stator blade support member housing 25. Due to the difference, it is possible to introduce cooling air having a high flow velocity with a small amount of cooling air. As described above, the air introduced into the cooling air cavity CC flows out into the space I from the gap of the cover 26, flows into the gap between the stationary blade 16 and the moving blade 17, and is used for cooling the turbine.

Next, the passage structure of the cooling air of the moving blades 17 in the turbine section will be described with reference to FIGS. 10 to 14. First, the mounting structure of the moving blade 17 to the disk 18 will be described with reference to FIGS. 10 to 12. The rotor blade 17 has a shank portion 17b formed on the opposite side (disc mounting side) via a rib portion 17a parallel to the outer peripheral surface of the disc 18. The base end of the shank portion 17b is a dovetail-shaped fitting portion 17c, which is fitted into the fitting holes 18a, 18a ... It is used as a radial stopper.

Further, in the fitting hole 18a, the fitting portion 1
There is a gap G as shown in FIG. 12 in order to form an air pool for introducing cooling air to the moving blade 17 between the tip of the moving blade 17c and the moving blade 17 wobbles in the radial direction. For positioning in the radial direction, a positioning projection 18b is projected from the disk 18 in the fitting hole 18a so as to abut the tip of the fitting portion 17c.

As shown in FIGS. 13 and 14, the shank portion 17b has a conical hole-shaped cooling air hole h formed therein, and a cooling air hole (not shown) formed in the moving blade 17 is formed.
Is in communication with Then, the fitting portion 17 of the cooling air hole h
As shown in FIG. 12, the opening at the tip of c is displaced from the contact position of the positioning protrusion 18b so as to face the gap g formed between the tip of the fitting portion 17c in the fitting hole 18a. , It is possible to introduce air.

As described above, with respect to the cooling air hole provided in the moving blade 17, the gap g provided in the fitting hole 18a is used as an air reservoir and air is supplied from the tip of the shank portion 17b (fitting portion 17c). Is introduced. Next, the cooling air passage structure to the gap g will be described with reference to FIGS. 10 and 11. Disk 1 with rotor blades 17 mounted radially on the outer circumference
The reference numeral 8 is provided around the drive shaft 19. The disk 18 shown in FIG. 10 is the uppermost disk 18A in the combustion air passage, and has gears 18e and 18e on the upper and lower sides so as to mesh with another disk 18B and the like. (The upper and lower directions of this combustion air are referred to as the front-rear direction.) The protruding portion 18 provided with this gear 18e to the upper side
At f, a cooling air hole 18d is formed in a penetrating manner in the vertical tilt direction. And the front and rear protrusions 18f and 18f
On the outer peripheral side, disc-shaped seal members 20 and 21 respectively covering the front surface and the rear surface of the disk 18 are provided.

Among the seal members 20 and 21, between the seal member 20 and the front surface of the disk 18 (18A),
A gap serving as the cooling air passage D is formed, and a guide vane 20 a is projected from the inner surface of the seal member 20.
The cooling air is supplied from the air chamber E around the drive shaft 19 formed in front of the disk 18A as shown in FIG.
It is introduced into the cooling air passage D via 8d and guided in the outer peripheral direction of the cooling air passage D by the guide vanes 20a. At the outer peripheral portion of the cooling air passage D, a step is formed to form a fitting portion with the disc 18, and the fitting portion communicates with the disc 18 and the cooling air passage D. A cutout portion 18c is formed, and the cutout portion 18c is formed.
Communicate with the front side of the fitting hole 18a. In this way, the cooling air guided in the cooling air passage D in the outer peripheral direction is introduced into the gap g in the fitting hole 18a through the notch portion 18c.

In the vicinity of the outer peripheral side of the cutout portion 18c, a circumferential positioning projection 20b is provided so as to abut against the disc 18 from the inner wall surface of the seal member 20, whereby the disc is provided. 18 and its fitting hole 1
The front and rear directions of the moving blade 17 fitted in the 8a are positioned. Further, the outer peripheral portion of the seal member 20 is fitted into the rib portion 17a of the moving blade 17, so that the stationary blade 16
The combustion air passage communicating with the moving blades 17 and the cooling air passage in the seal member 20 are sealed so as to be isolated from each other. The same applies to the seal member 21 on the rear surface side.

The above is related to the cooling structure of each part corresponding to the high heat generation of the turbine gas of the gas turbine in order to improve the output characteristics, and finally, to the high pressure of the turbine gas for improving the output characteristics. Regarding the configuration of the inter-stage duct 13 in the compressor for reducing the pressure loss, FIG.
5 will be described. Diffuser 12 of the front compressor 12
c and the impeller 14a of the rear-stage compressor 14, in the inter-stage duct 13 that is connected to the outlet of the front-stage diffuser 12c at the upper end, in the horizontal direction (axial direction) to remove the swirling flow. The front exit guide vane 13a is formed. Below that, an inter-stage duct chamber 13b having an enlarged volume is formed. The inter-stage duct chamber 13b
Does not restrain the flow from the front-stage inlet guide vane 13a, and reduces the flow velocity evenly throughout. A lower stage inlet guide vane 13c that is arranged in the vertical direction (radial direction) and communicates with the inlet of the rear stage impeller 14a is formed below it in order to reduce the remaining swirling flow.

Thus, in the interstage duct 13, the air that has been uniformly rectified as a whole by the reduction of the flow velocity in the interstage duct chamber 13b and the removal of the swirling flow due to the arrangement of the guide vanes is sent to the rear stage compressor 14 Can be sent to the impeller 14a.

[0050]

The present invention has the following effects because it is configured as described above in order to improve the output characteristics of the gas turbine. First, to improve output characteristics,
Although the combustion temperature of the combustor is increased, a cooling structure corresponding to the combustion temperature is required in each part, particularly in the combustor, the turbine intake duct below the combustor, and the turbine part. Among them, first, in the combustor, the arrangement position of the cooling air hole is configured as in claim 1, so that the air introduced into the combustor body from the cooling air hole is in the combustor body. When the liquid fuel dripping on the sliding part of the above is hit, the liquid fuel is scattered into the space of the premixing chamber to ensure sufficient mixing of the liquid fuel and air in the premixing chamber and to secure the NO _X reducing effect. In addition, the sliding portion is in the vertical direction, and the introduction of air from the cooling air holes eliminates the swirling of air in the premixing chamber, thereby eliminating the problem of lowering combustion efficiency.

Further, in the spark plug arranged in the combustor of the gas turbine, since the cooling air passage structure is constituted as described in claim 2, in the body of the spark plug, the air is discharged from the space in the outer cylinder. Since the cooling air is introduced through a gap smaller than the gap, dust itself that may clog the air gap cannot enter, and the problem of poor ignition can be solved.

Further, since the cooling structure of the turbine intake duct is constructed as described in claim 3, the turbine intake duct is repeatedly cooled in three ways, that is, spray cooling, convection cooling, and film cooling, and a small amount of cooling is performed. A cooling effect is obtained with a cooling air, loss of air pressure on the compressor side can be suppressed, and thermal deformation of the wall material is avoided by the configuration of the slit and the seat, and the convection cooling part associated with the thermal deformation can be avoided. The obstruction of the air flow from the film cooling section to the film cooling section can be avoided.

Further, with respect to the stationary blade supporting mechanism of the turbine portion, since it is configured as in claim 4, it is possible to send the cooling air to the stationary blade supporting member, suppress the thermal deformation thereof, and prevent the air flowing to the turbine from flowing. Can handle high temperature and high pressure. Further, since the flow velocity of the cooling air can be increased depending on the arrangement direction of the through holes, the cooling effect can be enhanced with a small amount of air, the amount of cooling air introduced from the compressor can be suppressed, and the pressure loss can be suppressed. .

With respect to the cooling air passage structure of the moving blade in the turbine portion, since it is configured as in claim 5, it is possible to adopt a moving blade having a shank portion having a dovetail shape whose fitting portion to the disk can be easily processed. It is possible and contributes to cost reduction. Even when the moving blade of this shape is adopted, the opening of the cooling air hole at the tip of the dovetail-shaped portion communicates with the gap in the fitting hole to ensure the introduction of cooling air to the moving blade. At the same time, positioning of the moving blades in the radial direction of the disk can be ensured by the positioning projections protruding from the disk.

With regard to increasing the gas pressure, which is one of the factors for improving the output characteristics, the compressor is configured as in claim 6, so that the air flow is uniformly rectified in the interstage passages. , It can be sent to the compressor in the latter stage, pressure loss can be reduced, and it can contribute to high gas pressure. Moreover, this can be realized at low cost.

[Brief description of drawings]

FIG. 1 is an overall side sectional view of a gas turbine.

FIG. 2 is a side sectional view of a combustor according to the present invention.

FIG. 3 is a side partial cross-sectional view showing a spark plug mounting structure according to an embodiment of the present invention.

FIG. 4 is a side partial cross-sectional view of a spark plug of another embodiment.

5 is a side sectional view showing a cooling structure of the turbine intake duct 15. FIG.

FIG. 6 is a front view of a portion of the double wall portion of the scroll 15A where a slit S and a seat SP are arranged.

FIG. 7 is a partially enlarged side sectional view showing a cooling structure of a turbine intake duct 15.

FIG. 8 is a side sectional view showing a cooling structure for a support mechanism of a stationary blade 16.

9 is a sectional view taken along line ZZ in FIG.

FIG. 10 is a partial side sectional view of a moving blade 17 portion.

FIG. 11 is a partial front view of the same.

FIG. 12 is a partial front view showing how the shank portion 16a of the rotor blade 16 is fitted to the disk 17.

FIG. 13 is a front cross-sectional view showing a structure in which a cooling air hole h is formed in a shank portion 16a of a moving blade 16.

FIG. 14 is a side sectional view of the same.

FIG. 15 is a side sectional view showing an interstage passage structure in a multistage centrifugal compressor.

FIG. 16 is a side sectional view of a conventional combustor.

FIG. 17 is a side sectional view showing a conventional spark plug mounting structure.

FIG. 18 (a) is a perspective view of a conventional blade having a fitting portion having a plurality of fitting step portions at the tip of the shank portion, in which cooling air is introduced from the side of the shank portion. , (B) are perspective views of a type in which cooling air is introduced from the side and the tip of the shank portion, and (c) is (b).
FIG. 3 is a perspective sectional view of the illustrated blade.

FIG. 19 is a side cross-sectional view of a structure in which air is introduced to the side of the rotor blade shank from a cooling air passage formed along a duct fixed to the stationary blade.

FIG. 20 is a side sectional view of a structure in which a cooling air hole communicating with a fitting hole of a moving blade is formed in a disk.

FIG. 21 is a side sectional view of a structure in which a cooling air passage communicating with a fitting hole of a moving blade is formed between a disc and a seal member.

FIG. 22 is a side sectional view showing an interstage passage structure of a conventional multistage centrifugal compressor.

[Explanation of symbols]

 1 Outer Cylinder 2 Combustor Main Body 2a Upper End 2b Short Diameter 2c Long Diameter 3 Liner 4 Liquid Fuel Injection Nozzle A Premixing Chamber B Combustion Chamber C Sliding Surface H Cooling Air Hole P Spark Plug 6 Body 6a Cooling Air Hole 7 Electrode 8 Insulator 9 Spark plug receiver AG Air gap BG Gap 12 Pre-stage compressor 12c Diffuser 13 Inter-stage duct 13a Pre-stage outlet guide vane 13b Inter-stage duct chamber 13c Rear stage inlet guide vane 14 Rear stage compressor 14a Impeller 15 Turbine intake duct 15A ・ 15B Scroll 15a, 15b, 15c, 15d Wall material IH Blow hole S Slit SP Batting seat (spacer) C1 Blow cooling part C2 Convection cooling part C3 Film cooling part 16 Stator blade 16a Claw part 17 Moving blade 17a Rib part 17b Shank part 17c Fitting Part 18 Disc 18a Fitting hole 18b Positioning protrusion 18c Cutout 18d Cooling air hole 19 Drive shaft 20 Sealing member 20a Guide vane 20b Positioning protrusion 24 Stator vane supporting member 25 Stator vane supporting member housing 25a Cooling air introducing hole h Cooling air hole g Gap D Cooling air passage E Air Room

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI technical display location F02C 7/266 F02C 7/266 (72) Inventor Mari Naito 1 Chayacho, Kita-ku, Osaka City, Osaka Prefecture No. 32 Yanmar Diesel Co., Ltd. (72) Inventor Norikazu Imai No. 32, No. 32 Chayamachi, Kita-ku, Osaka City, Osaka Prefecture Yanmar Diesel Co., Ltd.

Claims (6)

[Claims] 1. A combustor for a gas turbine, wherein an upper end portion of a main body of a combustor which is a vertical cylinder is bent horizontally outward to provide an air intake port, and a liquid is provided near the inside of the air intake port. In a configuration in which a fuel injection nozzle is arranged and a premixing chamber is provided between a liner vertically arranged in the center of the combustor body and a vertical wall surface of the combustor body, the upper end of the combustor body is bent. A slidable portion of the liquid fuel is provided from the portion toward the premix chamber, and the air introduced from the cooling air hole formed in the vertical wall surface of the combustor body hits the lower end portion of the slidable portion. A gas turbine characterized by. 2. A spark plug attached to a combustor of a gas turbine, wherein a gap between a member covering an outer opening of a cooling air hole formed in a body of the spark plug and the body is
A gas turbine characterized in that it is configured to open smaller than an air gap of the spark plug with respect to a cooling air intake space. 3. A turbine intake duct communicating from a combustor of a gas turbine to a turbine section, wherein a wall portion of the turbine intake duct is partially formed as a double wall, and an outer wall of the double wall is formed as an air compressor. An air hole is formed in the form of a film from the convection cooling section of the double wall, followed by a blast cooling section for blasting the air introduced from the hole to the inner wall. In a structure in which a film cooling portion that flows out and cools a single wall portion is formed, the inner wall of the double wall convection cooling portion in the vicinity of the film cooling portion,
A gas turbine, characterized in that a slit is provided, and a pad is provided to secure a gap between an outer wall and an inner wall which serves as an air communication passage from the convection cooling section to the film cooling section. 4. A structure in which a stationary blade of a gas turbine is supported by an annular stationary blade supporting member, and the stationary blade supporting member is supported in a tubular stationary blade supporting member housing, wherein the stationary blade supporting member housing is provided. And a through hole for introducing air is provided in a tangential direction of an outer peripheral circumference of the vane support member, while an air introduction path communicating from the compressor outlet to the outside of the vane support member housing is formed. And a gas turbine. 5. A shank portion of a moving blade in a gas turbine is fitted into a fitting hole formed on an outer circumference of a disk, and a fitting portion to be fitted into the fitting hole formed at a tip of the shank portion is dovetailed. In the shape, a cooling air hole is formed from the tip of the shank portion to the moving blade, and the cooling air hole is communicated with the fitting portion of the shank portion in the fitting hole. The gas turbine is characterized in that a positioning projection that abuts the tip of the fitting portion of the shank portion is projected from the disc while ensuring a gap that serves as an air reservoir. 6. A multi-stage centrifugal compressor for a gas turbine, wherein the interstage passage is a volume expansion chamber.