JPH05288002A - Air-cooled ceramic static blade - Google Patents

Abstract

PURPOSE:To enable usage of high-temperature combustion gas and provide a high-efficiency gas turbine by decreasing a temperature of a ceramic blade. CONSTITUTION:A thin plate 27 formed with a plurality of minute ports 28 is sandwiched between a ceramic blade 21 and a core bar 24 with gaps 25 and 26. Cooling air 31 is blown to an inner surface side of the blade 21 through the plural minute ports 28 formed on the thin plate 27.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air-cooled ceramic stator vane suitable for use in gas turbines, jet engines and the like.

[0002]

2. Description of the Related Art For example, a gas turbine, as shown in FIG. 4, supplies the air compressed by a compressor 1 to a combustor 2 where it is mixed with fuel and burned to generate combustion gas. It is introduced into the turbine unit 3 and converted into rotational energy, and the rotational energy is used to drive the generator 4 to obtain electric power.

The turbine section 3 is provided with stationary blades 5 and moving blades 6 as schematically shown in FIG. 5, and the high temperature combustion gas supplied from the combustor 2 shown in FIG. Rotating energy can be obtained by injecting the moving blades 6 through the stationary blades 5. This vane 5 is a combustor 2
It has to withstand a combustion gas temperature of about 1300 degrees Celsius supplied from, for example, and therefore a ceramic material has been developed.

6 and 7 show a conventional vane 5. That is, the vane 5 is divided into three parts, that is, the blade part 7 made of ceramic, the inner shroud 8 made of ceramic, and the outer shroud 9 made of ceramic so as to be easy to manufacture and avoid excessive thermal stress. Metal inner shroud 10 and metal outer shroud 1
It was a hybrid structure in which it was sandwiched by 1 and clamped with a cored bar 12 to be integrally fixed.

The inner shroud 8 made of ceramic
And an inner shroud 10 made of metal, and an outer shroud 9 made of ceramic and an outer shroud 11 made of metal.
A cushioning material 13 is inserted between each of these parts to make uniform the tightening load and to serve as a heat shield.

Further, several cooling holes 14 are bored in the core metal 12, and a heat insulating material 16 is provided between the core metal 12 and the ceramic blade 7 and the inner and outer shrouds 8 and 9.
Has been inserted. Then, in the cooling hole 14 of the core metal 12,
Cooling air 15 is caused to flow from the outside to the inside to cool the inside of the cored bar 12 to reduce the difference in thermal expansion between the ceramic and the metal.

[0007]

By the way, the conventional ceramic vane 5 as described above can only withstand a gas temperature of about 1300 degrees Celsius. However, in recent years, the demand for the development of highly efficient gas turbines has increased, and for this purpose, there has been a demand for providing vanes that can withstand higher temperatures.

The present invention has been made to solve the above-mentioned problems of the prior art. In order to provide a highly efficient gas turbine, the temperature of the ceramic blade portion is lowered,
An object of the present invention is to provide an air-cooled ceramic stator vane capable of using high-temperature combustion gas.

[0009]

In order to solve the above-mentioned problems, the present invention sandwiches the inner and outer sides of a ceramic blade with an inner shroud and an outer shroud made of ceramic, respectively, and penetrates them. In a ceramic vane tightened with a core metal and integrally fixed, a thin plate with a large number of pores formed between the blade part and the core bar is provided with air gaps for both the blade part and the core bar. While inserting so as to keep it, air discharge means is formed on the trailing edge side of the blade part, and cooling air supplied between the core metal and the thin plate is passed through a large number of pores formed in the thin plate to make a ceramic blade. The cooling air is blown out to the inner surface side of the portion, and this cooling air is discharged into the high temperature gas from the air discharging means formed on the trailing edge side of the blade portion.

[0010]

[Operation] According to the above means, the cooling air is supplied between the cored bar and the thin plate, so that the cooling air passes through a large number of pores formed in the thin plate, and the inner surface side of the ceramic blade portion. Since the core metal is cooled by the cooling air, the inner surface side of the blade is cooled by impingement. Therefore, the temperature of the ceramic blade can be lowered by about 200 degrees from the conventional temperature, and the combustion gas having a temperature higher by that amount can be introduced into the gas turbine for use.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the air-cooled ceramic stator vane according to the present invention will be described in detail below with reference to FIGS. Here, FIG. 1 is a sectional view showing an embodiment of an air-cooled ceramic vane according to the present invention with a part cut away, and FIG. In addition,
In FIGS. 1 and 2, the same parts as those in FIGS. 6 and 7 are designated by the same reference numerals, and a description thereof will be omitted.

The air-cooled ceramic stator vane according to the present invention is divided into three parts, a ceramic blade part 21, a ceramic inner shroud 22 and a ceramic outer shroud 23, which are made of metal. It has a hybrid structure in which it is sandwiched between the inner shroud 10 and the outer shroud 11 made of metal, and is tightened by a core metal 24 to be integrally fixed. The ceramic blades 21 are fixed to the ceramic inner shroud 22 and the ceramic outer shroud 23 by spigot method. Reference numeral 20 indicates this spigot portion.

The core 24 and the ceramic wing 2
A thin plate 27 is inserted between the shroud 1 and the inner and outer shrouds 22 and 23 so as to keep the spaces 25 and 26, respectively. A large number of pores 28 are formed in this thin plate 27. Further, one end side of the thin plate 27 is welded to the metal outer shroud 11 as indicated by reference numeral 29, and the other end side is inserted into the groove 30 formed in the metal inner shroud 10 without any clearance. .. Further, the trailing edge side of the wing portion 21 is formed to have an open cross-section portion structure as indicated by reference numeral 32 in FIG.

The operation of the air-cooled ceramic stator vane according to the present invention thus constructed will be described. The core metal 24 and the thin plate 27 are explained.
The cooling air 15 is supplied to the space 25 between the cooling air 15 and the cooling air 15 and blows out to the inner surface side of the ceramic blade portion 21 through the large number of pores 28 formed in the space 25. That is, the inner surface side of the blade portion 21 is impingement cooled by the cooling air 15. Then, the cooling air 31 that has cooled the blade portion 21 and whose temperature has risen passes through the gap 26 between the inner surface of the blade portion 21 and the thin plate 27, and then flows from the open cross-section portion 32 on the trailing edge side of the blade portion 21 into the high temperature gas. It is discharged inside.

FIG. 3 is a characteristic diagram comparing the cooling efficiencies of the air-cooled ceramic vane according to the present invention and the conventional vane, and the curve C shows the cooling efficiency of the air-cooled ceramic vane according to the present invention on the one hand. , Curve D shows the cooling efficiency of the conventional vane. That is, the conventional vane 5 shown in FIGS. 6 and 7 is one in which cooling air 15 is made to flow from the outside to the inside of the cooling hole 14 formed in the core metal 12 to cool the core metal 12 itself. The cooling efficiency at this time is as shown by the curve D. On the contrary,
The air-cooled ceramic stator vane according to the present invention positively blows the cooling air 31 through the large number of pores 28 formed in the thin plate 27 so as to collide with the inner surface side of the ceramic blade portion 21. Is cooled, and the cooling efficiency is as shown by the curve C.

[0016]

As described in detail above, according to the present invention,
The inner surface side of the ceramic blade portion is positively impingement-cooled, and therefore, the temperature of the ceramic blade portion can be lowered by about 200 degrees from the conventional temperature. Therefore, the combustion gas at a high temperature can be introduced into the gas turbine and used as much as the temperature of the ceramic blade portion is lowered. It becomes possible to provide a gas turbine.

[Brief description of drawings]

FIG. 1 is a partially cutaway plan view showing an embodiment of an air-cooled ceramic stator vane according to the present invention.

FIG. 2 is a perspective view seen from a portion cut along line BB in FIG.

FIG. 3 is a characteristic diagram showing a comparison of cooling efficiencies of an air-cooled ceramic stator vane according to the present invention and a conventional ceramic stator vane.

FIG. 4 is a system diagram showing a general configuration of a gas turbine.

5 is a partial cross-sectional view schematically showing a turbine section in FIG.

FIG. 6 is a sectional view showing a conventional ceramic vane with a part cut away.

7 is a sectional view taken along the line AA of FIG.

[Explanation of symbols]

 15 Cooling Air 21 Wings 22 Ceramic Inner Shroud 23 Ceramic Outer Shroud 24 Core Bar 25 Void 26 Void 27 Thin Plate 28 Pore 31 Cooling Air 32 Open Cross Section

Claims (3)

[Claims] 1. A ceramic vane in which an inner side and an outer side of a ceramic blade part are sandwiched between an inner shroud and an outer shroud made of ceramic, respectively, and which are integrally fixed by tightening a core bar penetrating therethrough. A thin plate having a large number of pores formed between the wing portion and the core metal is inserted so as to maintain air gaps in both the wing portion and the core metal, and air is provided on the trailing edge side of the wing portion. Forming a discharge means,
The cooling air supplied between the core metal and the thin plate is blown out to the inner surface side of the ceramic blade portion through a large number of pores formed in the thin plate, and the cooling air is supplied to the trailing edge side of the blade portion. An air-cooled ceramic stationary vane characterized in that the air is discharged into high-temperature gas from the air discharge means formed in the above. 2. The inner and outer sides of a ceramic wing are sandwiched between an inner shroud and an outer shroud made of ceramic, respectively, and are fixed integrally by being tightened by a core bar penetrating them. An air-cooled ceramic stationary vane in which cooling air is supplied to the inner surface of the blade, wherein a trailing edge of the ceramic blade has an open cross-section structure. 3. A ceramic vane in which an inner side and an outer side of a ceramic blade part are sandwiched by a ceramic inner shroud and an outer shroud, respectively, and are integrally fixed by tightening a cored bar penetrating therethrough. A thin plate with a large number of pores formed between the blade and the core metal is inserted so as to maintain a gap in both the blade and the core metal, and the trailing edge side of the blade is opened. Formed in a cross-sectional structure, the cooling air supplied between the core metal and the thin plate is blown to the inner surface side of the ceramic blade through a large number of pores formed in the thin plate, and the cooling air is discharged. An air-cooled ceramic stationary vane, characterized in that the air is discharged from the trailing edge of the blade portion into high temperature gas.