JP2726922B2 - Gas turbine combustor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas turbine combustor for continuously generating high-temperature combustion gas used as a working gas for a gas turbine, and more particularly to a ceramic liner for a gas turbine combustor. The present invention relates to a structure for supporting a gas turbine body on a ceramic scroll.

[0002]

2. Description of the Related Art With the rapid progress of ceramic forming / firing technology in recent years, ceramics from various heat-resistant structural parts to working parts such as internal combustion engine pistons, etc., which require high precision, have come to be manufactured. On the other hand, attention has been paid to the development of a cogeneration system that can flexibly cope with heat and electric load fluctuations and requires a short warm-up operation time, and a compact, high-output gas turbine has been incorporated. In order to further improve the thermal efficiency, the use of ceramic parts has been considered. A system was introduced that introduced the gas without cooling it. Therefore, it is necessary to generate higher-temperature combustion gas also in the combustor, and ceramics have been used for liners and the like as in gas turbines. Incidentally, in the combination of the combustor using such ceramic parts and the gas turbine body, the gas inlet temperature of the turbine reaches an extremely high temperature of about 1350 ° C., and the cooling loss is greatly reduced. At the same time, by performing heat recovery by facing heat exchange between the turbine exhaust gas and the intake air for the combustor in the regenerative heat exchanger, the thermal efficiency can be greatly increased (to about 42%).

[0003]

However, although the dimensional accuracy of ceramic parts has been ensured, they can be used aggressively in parts where heat resistance is required. Because they are brittle and have a very low coefficient of thermal expansion compared to parts, even when ceramic parts and metal parts are combined, they loosen and rattle at high temperatures or the mounting force increases, causing cracks in the ceramic parts. I often come across situations that said it would happen. Therefore, in order to fix the ceramic parts at a high temperature part, it is necessary to support the ceramic parts so that a necessary mounting force remains while avoiding an increase in thermal stress.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems that occur when supporting a ceramic part in a high-temperature area, and uses a ceramic liner that internally generates a high-temperature gas to resist vibration loads during operation. Further, a gas turbine combustor capable of absorbing a difference in thermal expansion from a metal casing to secure a center ring in a self-centering manner, preventing a side contact or the like, and connecting to a scroll of a gas turbine body. It is intended to be.

[0005]

In order to achieve the above object, a gas turbine combustor according to the present invention has a) a fuel supply means and a fuel ignition means. In a gas turbine combustor having a cylindrical ceramic liner supported by being connected,
b) The liner is provided in a cylindrical metal combustor casing connected to the metal scroll casing around the scroll, and between the periphery of the liner and the combustor casing and between the periphery of the scroll and the scroll casing. To form a combustion air passage communicating with each other, c)
The inner end of the liner is opened, and the opening periphery and the opening periphery of the connecting portion of the scroll are formed in a spherical arc shape corresponding to each other, and d) an outer end side of the liner in the combustor casing. In addition to fixing a cylindrical metal liner support, a ceramic compression spring is compressed between the inner end of the liner support and the liner, and the liner is moved toward the connection portion of the scroll. It is energizing.

According to a second aspect of the present invention, e) the peripheral edge of the opening of the connecting portion of the scroll is formed in a concave spherical arc shape,
It is preferable that the inner end side peripheral edge of the liner is formed in a convex spherical arc shape.

According to a third aspect of the present invention, f) the end wall of the outer end of the liner is formed in a ring shape inclined toward the inner center from the outer peripheral portion, and the ceramic is formed on the inner end side of the liner support. A plurality of compression springs may be arranged at equal intervals in the circumferential direction, or g) the liner support may be provided with combustion air from a central opening provided at an outer end of the liner. It is even more preferable to provide a combustion air supply opening provided with a swirler (swirl) guide vane (swirl).

[0008]

According to the gas turbine combustor of the present invention having the above-described structure, the ceramic liner of the combustor connected to the ceramic scroll of the gas turbine body has a scroll connection portion at the inner end of the opening. The liner is connected to the opening of the gas receiving portion, and the liner is urged toward the connecting portion of the scroll through a ceramic compression spring by a liner support fixed to the outer end of the liner. The connected state of the scroll is maintained. At this time, by setting an appropriate biasing force, the ceramic liner can be stably connected to the scroll of the gas turbine body by resisting the vibration load during operation and absorbing the difference in thermal expansion with the metal casing. It can be elastically supported. Since the liner and the scroll are made of ceramic and the biasing means of the liner are also made of a ceramic compression spring, even if the present combustor generates an unusually high-temperature combustion gas such as 1350 ° C., The biasing force does not weaken due to creep phenomenon or the like. In addition, since the peripheral edge of the opening of the connecting portion between the liner and the scroll is formed in a spherical arc shape (arc shape forming a part of the spherical shape), even if the liner or the scroll slightly moves, the self-centering is performed. The center ring is secured, the one-side contact is prevented, and a stable connection state is secured.

In the present combustor, a ceramic liner is
High-temperature combustion air is supplied from an air passage between the surrounding casing and fuel, and fuel is supplied by fuel supply means and mixed with the combustion air. By being ignited, combustion gas at an extremely high temperature can be generated. For this reason,
In addition to scrolls, for example, for a ceramic gas turbine in which the nozzle and turbine blade are each made of ceramic, the cooling loss is greatly reduced by introducing the nozzle and turbine blade at an ultra-high temperature without cooling midway. In addition, the heat efficiency can be greatly improved in conjunction with the recovery of exhaust heat to the high-temperature combustion gas. Incidentally, in the case of the conventional metal scroll, the supply combustion gas temperature is 960 ° C.
Although the temperature has been suppressed to a low level before and after, it is possible to increase the temperature to about 1350 ° C. by adopting ceramic parts, so that the gas turbine thermal efficiency can be greatly increased (to about 42%).

[0010] In the combustor according to the second aspect, the concave spherical arc-shaped opening edge on the scroll side and the convex spherical arc-shaped opening edge on the liner side are fitted and connected without difficulty, and if the liner is in operation. The centering with the scroll is reliably maintained even if the tilt is slightly caused by vibration or the like, and the connected state is stably maintained.

According to the third aspect of the present invention, the biasing force of the ceramic compression scroll acts from the peripheral portion to the center portion of the liner, so that the center of the liner is displaced even if the scroll side is slightly moved and the center is displaced. The inclination is allowed, and the connected state between the liner and the scroll is maintained.

[0012] In the combustor according to the fourth aspect, mixing of the fuel and air supplied into the liner is sufficiently promoted, and the combustion state is favorably maintained and stabilized.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a combustor for generating a high-temperature combustion gas according to the present invention.

FIG. 1 is a longitudinal sectional view showing a liquid fuel diffusion combustion type high temperature combustion gas generating combustor mounted on a ceramic gas turbine according to one embodiment of the present invention, and FIG.
FIG. 3 is a front view showing an inner surface of a liner support used in the combustor of FIG. 1, and FIG. 4 is a longitudinal sectional view of a support ring of the combustor of FIG. It is.

As shown in FIG. 1, a gas turbine combustor 1 according to the present embodiment is a liquid fuel diffusion combustion type combustor, and this combustor 1 is suitable for use in combination with a gas turbine body 5. Both are incorporated in a cogeneration system that can flexibly respond to changes in the heat-to-electricity output ratio and requires a short warm-up operation time. In the combustor 1, a cylindrical metal casing (combustor casing) 10 is provided at an inner end thereof on a connecting short pipe flange 52 of an outer peripheral portion of a metal casing (scroll casing) 51 arranged laterally of the gas turbine body 5. Side flange 1
2, and inside the casing 10,
A cylindrical ceramic liner 20 is housed concentrically. A lid 14 is hermetically attached and closed to a flange 13 around an inner end side (free end side) opening of the casing 10. The lid 14 penetrates a central opening 14 a of the lid 14 and serves as a fuel supply means. A liquid fuel injection device 48 is disposed in an airtight manner, and an ignition plug 49 as an ignition means is hermetically attached to the opening 15 a of the casing peripheral wall 15.

An inner end 21 of the ceramic liner 20 is opened, and the inner end 21 is connected to and supported by a gas receiving portion 56 of a ceramic scroll 55 on the gas turbine main body 5 side supplied with a high-temperature combustion gas. You. Liner 2
0 has an end wall 23 which is gradually inclined toward the outside center and has an opening 22a at the center. The opening edge 21a of the inner end 21 and the opening edge 56a of the gas receiving portion 56 of the scroll 55 have a convex spherical arc shape (part of a convex spherical shape) having a center point O on the liner central axis X and a radius R. ) And a concave spherical arc (a part of a concave sphere) in cross section.
The liner 20 is maintained while maintaining the contact state between 1a and 56a.
Can be slightly tilted in any direction around the center point O. The injection nozzle 48a of the fuel injection device 48 faces the central opening 22a of the end wall 23.
Nine igniters 49 a are slightly inserted into the liner 20 from one of the plurality of openings 24 a on the upper end wall side of the liner peripheral wall 24. The openings 24a not used for mounting the spark plugs 49, together with the openings 24b formed in the peripheral wall 24 below and adjacent thereto, play a role of secondary air supply of combustion air supply means. Further, auxiliary combustion air is supplied to the intermediate portion of the peripheral wall 24,
An opening 24c is provided for inserting an air or steam supply pipe (not shown) for performing air or steam injection for suppressing the generation amount of air.

On the end wall 23 of the outer end 22 of the liner 20 as described above, a cylindrical metal liner support 30 is provided with an inner peripheral recess 13 of the free end flange 13 of the casing 10.
The liner support 30 is inserted through an opening at the end of the casing 10 with the lid 14 removed. The liner support 30 has a flange 32 attached to a free end of the cylindrical peripheral wall 31, a bottom disk 33 attached to a liner side end of the cylindrical peripheral wall 31, and an upper portion of the liner peripheral wall 24 on the liner side outer peripheral portion of the bottom disk 33. A short tube 34 that loosely supports the end wall side is connected.

A plurality of openings 31a for introducing combustion air from an annular space S1 as a passage for supplying combustion air to the casing 10 are formed in the cylindrical peripheral wall 31. Inside the bottom disk 33, a plurality of holes 33a for accommodating a plurality of ceramic compression coil springs 35 of the urging means of the liner 20 are formed at equal intervals in a circumferential direction, and the fuel injection device is formed. A combustion air supply opening 33c (FIG. 3) for supplying the primary combustion air into the liner 20 in a swirl shape is formed around the central opening 33b into which the front end of the 48 is inserted. As shown in FIG. 3, a number of helical guide vanes (also referred to as swirlers) 33d for swirl generation are mounted on the combustion air supply opening 33c.

On the upper end wall 23 of the liner 20, a contact surface 41 with the ceramic compression coil spring 35 is flat and a contact surface 42 with the end wall 23 is formed on the end wall 23 as shown in FIG.
Ceramic support ring 40 with the same inclination
Is placed, the urging force of the coil spring 35 acts from the periphery of the liner 20, and even if the gas receiving unit 56 moves a little and the center shifts and the liner 20 tilts, the liner 20 is The contact between the inner end side 21 and the opening peripheral edges 21a and 56a of the gas receiving portion 56 of the scroll 55 can always be ensured.

The combustion air passage is formed in an annular space S1 between the casing 10 and the liner 20 and the liner support 30.
And the opening 31a of the cylindrical peripheral wall 31 and the primary combustion air supply opening 33c of the bottom disk 33 communicating therewith, and the secondary combustion air supply openings 24a and 24b of the liner peripheral wall 24 also communicating with the annular space S1. And a supplementary opening 24c.

The system for supplying combustion air will be described. Referring to FIG. 2, a compressor C which is rotationally driven by a rotor (not shown) in the gas turbine body 5 is shown.
The compressed air sucked from the bell mouth M and compressed by the bellows M flows from the outermost space S2 of the scroll 55 to the duct D1.
Through the regenerative heat exchanger H, where the heat is recovered by the counter heat exchange with the turbine exhaust gas.
The temperature rises from 820C to 820C. The heated pressurized air is then sent from the regenerative heat exchanger H via the duct D2 to the outer peripheral second space S3 of the scroll 55 (FIG. 1).
From there, the combustion gas is supplied to the annular space S1, and it becomes possible to generate high-temperature combustion gas that reaches 1350 ° C. in the combustor 1. Therefore, the cooling loss in the gas turbine body 5 is greatly reduced, and the thermal efficiency thereof can be greatly increased (up to about 42%).

FIG. 5 is a longitudinal sectional view showing a gas premixed lean burn type combustor for generating high-temperature combustion gas using gas as fuel, and corresponds to FIG. The combustor 1 'of this embodiment differs from the combustor 1 of the above embodiment only in the type of fuel (the former is liquid fuel and the latter is gas), and has a common basic structure. Therefore, common constituent members are denoted by the same reference numerals as in the above-described embodiment, and description thereof is omitted. Only the differences will be described. As shown in FIG. 5, a pilot pilot burner 49 'is inserted through the central opening 14a of the lid 14, and the tip of the pilot burner 49' is inserted into the central opening 33b of the bottom disk 33. It faces inside the liner 20. Bottom disk 3
A plurality of fuel supply holes 33d 'for injecting a gaseous mixture of gaseous fuel and air are formed around the center opening 33b of the fuel cell 3, and a swirler 33d "is attached to the fuel supply hole 33d'. A distal end of a gas fuel injection device 48 'as a fuel supply means is disposed near the inlet of each fuel supply hole 33d' and slightly apart from the inlet, and the base end side of each gas fuel injection device 48 'is a lid. 14 penetrates an opening 14b formed around a central opening 14a of the liner 2.
A bypass valve 24d that changes the flow of air in order to appropriately control the air-fuel ratio is attached to the casing 10 so as to face the opening 24c of 0. Although these configurations are different from the combustor 1, all of these differences are based on the difference in the type of fuel, and the two have completely the same basic configuration and operation of the combustor itself.

[0023]

As described above, according to the gas turbine combustor of the present invention, the following excellent effects can be obtained.

(1) By stably and elastically supporting and incorporating a ceramic liner with a ceramic spring, it is possible to generate a high-temperature combustion gas which has never existed before.

(2) The ceramic liner can be elastically supported to further withstand the vibration load during operation and absorb the difference in thermal expansion with the metal support structure member, and at the same time, self-centering by spherical contact. In addition, it is possible to stably connect to the ceramic scroll on the gas turbine main body side while securing the center ring and preventing the one-side contact or the like.

(3) By integrating the combustor into the gas turbine, the gas supply path can be shortened, and the compactness is excellent in thermal efficiency.

According to the second aspect of the present invention, (4) even if the liner is slightly tilted due to vibrations during operation or the like, the centering with the scroll is securely held and the connection state is stably maintained. Is done.

According to the third aspect of the present invention, (5) the biasing force of the ceramic compression scroll acts from the periphery to the center of the liner, for example, when the scroll side slightly moves and the center is displaced. Also, the inclination of the liner is allowed, and the connected state between the liner and the scroll is maintained.

(6) Mixing of fuel and air supplied into the liner is sufficiently promoted, and a good combustion state is maintained and stabilized.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view showing a liquid fuel diffusion combustion type high temperature combustion gas generating combustor mounted on a gas turbine according to one embodiment of the present invention.

FIG. 2 is a front view showing the entire gas turbine equipped with the combustor of the present invention shown in FIG. 1;

FIG. 3 is a front view showing an inner surface of a joint of the liner support used in the combustor of FIG. 1 with the liner;

FIG. 4 is a longitudinal sectional view of a support ring of the combustor of FIG. 1;

FIG. 5 is a longitudinal sectional view showing a gas premixed lean burn type high temperature combustion gas generating combustor using gas as a fuel, and FIG.
FIG.

[Explanation of symbols]

 1.1 Combustor for Gas Turbine 5 Gas Turbine Main Body 10 Metal Casing 12 Flange 20 Ceramic Liner 21 Inner End Side of Liner 20 21 Opening Edge 22 Outer End 23 End Wall 30 Liner Support 33d Swirl Guide Blade 35 Ceramic Compression coil spring 40 Ceramic support ring 48/48 'Fuel injection device 49 Ignition plug 51 Metal casing 52 Flange 55 Scroll 56 Gas receiving part 56a Opening periphery S1 Annular space

 ────────────────────────────────────────────────── ─── Continuing from the front page Patent application Article 30 (1) is applied for THE AMERI CAN SOCIETY OF MECHANICAL ENGINEERS. (72) Inventor Yoichi Shrine 3-1-1 Higashikawasakicho, Kobe City, Hyogo Prefecture In the factory (56) References JP-A-59-134333 (JP, A) JP-A-57-88224 (JP, A) JP-A-1-111148 (JP, U)

Claims (4)

(57) [Claims] 1. A gas turbine combustor having a fuel supply means and a fuel ignition means, and having a cylindrical ceramic liner supported by being connected to a ceramic scroll of a gas turbine, The liner is provided in a cylindrical metal combustor casing connected to a surrounding metal scroll casing, and the liner is provided between the periphery of the liner and the combustor casing and between the periphery of the scroll and the scroll casing. A combustion air passage communicating with the scroller, an inner end of the liner being opened, and an opening edge and an opening edge of a connection portion of the scroll formed in a spherical arc shape corresponding to each other; A cylindrical metal liner support is fixed to the outer end of the liner in the casing, and the inner end of the liner support is A gas turbine combustor, wherein a ceramic compression spring is compressed between the liner and the liner to urge the liner toward the connection portion of the scroll. 2. The gas turbine combustor according to claim 1, wherein an opening periphery of the connection portion of the scroll is formed in a concave arc shape, and an inner end side opening periphery of the liner is formed in a convex arc shape. 3. An end wall of the outer end of the liner is formed in a ring shape inclined toward an inner center from an outer peripheral portion, and a plurality of the ceramic compression springs are formed in a circle on an inner end side of the liner support. The gas turbine combustor according to claim 1, wherein the combustors are arranged at equal intervals in a circumferential direction. 4. A combustion air supply opening provided with a guide blade for supplying combustion air in a swirl shape from a central opening provided at an outer end of the liner, wherein the liner support is provided. A combustor for a gas turbine according to any one of the above.