JPH04104101U - gas turbine blades - Google Patents

Abstract

(57) [Summary] [Purpose] To obtain a gas turbine blade that makes it possible to change the ratio of the amount of cooling air to the heat exchange air passage, and that can also be used for other purposes depending on the turbine load. . [Configuration] An air flow control orifice 9 with holes 3a and 3b having cross-sectional areas corresponding to the first and second air flows set by cooling calculations is connected to the gas turbine blade 1.
It was removably attached to the recess provided in the air intake hole 2 of. [Effect] By selecting and using an air flow control orifice, there is no need to newly manufacture gas turbine blades according to the load of the turbine, improving manufacturing efficiency and further reducing costs significantly.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention relates to a gas turbine blade for air-cooled rotor blades.

0002

[Conventional technology]

As is well known, gas turbine blades are used when the gas turbine rotates at full speed to achieve its maximum capacity. Made with maximum heat resistance so that it can withstand the hot ambient temperature when It is built. Conventional example 1 of such air-cooled rotor blades for gas turbines is generally is a gas turbine that forms one system of cooling air passages set by cooling calculations. It is known for its wings. In addition, in order to operate the gas turbine with high thermal efficiency, it is necessary to reduce the amount of cooling air as much as possible. It is also known that it is necessary to suppress the

0003 However, the gas turbine blade of Conventional Example 1 has an air inlet installed at the bottom of the blade. One system of heat exchange air passages that takes in air through the holes and pumps it to the downstream edge of the blade. As a result, the temperature at the downstream edge of the blade becomes particularly high, and as a result, the blade This created a temperature difference between the blades, which was one of the causes of reduced service life of the blades.

0004 In order to solve this technical problem, a gas turbine blade of conventional example 2 shown in Fig. 4 is proposed. Are known. FIG. 4 is a longitudinal cross-sectional view of this improved gas turbine blade, in which 1 indicates a gas turbine blade. Turbine blades, 2 is an air inflow hole, 3 is a first air passage, 4 is a second air passage, 5 is a gas An air outlet (not shown) is provided at the edge of the downstream side of the turbine blade 1, and 6 is a gas outlet. Air blowing holes provided on the upper surface of the turbine blade 1, 7 a heat exchanger provided on the inner wall of the air passage The promoting fins 8 are heat exchange protrusions.

[0005] This conventional example 2 is different from the conventional example 1 in which the first air passage is provided, and further includes a wing. Two systems of heat exchange air with a second air passage blowing out cooling air on the upper surface. It forms a passageway.

[0006] However, when the turbine load (output) is small, the temperature of the turbine blades is low. Therefore, it is desirable to suppress the amount of cooling air to increase the work efficiency of the turbine. However, the improved gas turbine blade of Conventional Example 2 does not allow this cooling air volume to be changed. The problem was that it was difficult to read. Therefore, Gaster manufactured for one purpose Bottle blades cannot be used for other purposes and must be manufactured each time, resulting in high manufacturing costs. However, gas turbines that can adjust the amount of cooling air and can be used for other purposes There was a request for the development of a bottle wing.

[0007]

[Problem that the idea aims to solve]

This idea solves the above-mentioned conventional technical problems and allows each of the two systems to use air for heat exchange. This makes it possible to change the ratio of cooling air volume to the passage, and also allows for use in other applications. The object of the present invention is to provide a gas turbine blade that can be used for other purposes.

[0008]

[Means to solve the problem]

When cooling gas turbine blades by heat exchange, the flow rate of cooling air is It is determined by the cross-sectional area of the hole. This idea focuses on this point and solves the above problems. It was completed by solving the problem.

[0009] In other words, this invention is based on the first air flow and the second air flow set by the cooling calculation. Air flow control orifices with holes of cross-sectional area corresponding to each air flow are used. It can be attached and detached to the recess provided at the entrance of the air inlet hole provided at the bottom of the gas turbine blade. It was installed.

0010

[Effect]

The air flow control orifice of this invention has two systems installed on the gas turbine blade. It is possible to introduce a preset ratio of cooling air flow into each heat exchange air passage. In both cases, simply by replacing the air flow control orifice mentioned above, the cooling air flow rate can be adjusted. It has the ability to freely change the ratio.

[0011]

【Example】

An embodiment of this invention will be described below with reference to the drawings. FIG. 1 is a longitudinal cross-sectional view of a gas turbine blade of this invention. , air inlet hole 2 provided at the bottom allows cooling air to be fed under pressure from a compressor (not shown). A recess is provided at the inlet of the air inlet hole 2, and the air inflow hole 2 is attached to the recess. The air is introduced into the first air passage 3 and the second air passage 4 through the air flow control orifice 9. The air flow passing through the second air passage 4 is caused by air flowing through the upper surface of the gas turbine blade 1. The air flow passing through the air path blown out from the air blowing hole 6 and passing through the first air passage 3 is as follows: Air is emitted from a blow-off hole (not shown) provided in the downstream end edge 5 of the gas turbine blade 1. The structure is such that an air path is formed. Note that the arrows in the diagram indicate the flow of cooling air. shows. Further, in the air passage, heat exchange promoting fins 7 are provided on the inner wall thereof. At the same time, air flows through the first air passage 3 and into the blow-off hole provided at the downstream end edge 5 of the blade. Protrusions 8 are provided on the inner wall surface near the edge of the downstream side of the air path to efficiently exchange heat. I have made it possible.

0012 FIG. 2 is a plan view of the part where the air flow rate control orifice 9 is attached, as seen from arrow A. The air flow control orifice 9 includes a through hole 3a corresponding to the first air passage 3 and a through hole 3a corresponding to the first air passage 3. A through hole 4a corresponding to the second air passage 4 is opened. This air flow control orifice The slot 9 is detachably attached to a recess provided at the entrance of the air inflow hole 2. Ru. This attachment means uses the centrifugal force that accompanies the rotation of the gas turbine to The air flow rate control orifice 9 is in close contact with the air inflow hole 2, so it must be fixed firmly. It is not necessary, and it is sufficient to fit it into the recess provided in the air inflow hole 2. In addition It goes without saying that if it is not removable, it may be fixed using conventional means. Nor.

[0013] FIG. 3 shows another embodiment of the air flow control orifice 9, in which the ratio of the cross-sectional area A through hole 3b corresponding to the first air passage 3 and a passage corresponding to the second air passage 4 with different The hole 4b is opened.

[0014]

【Effect of the invention】

According to this idea, the appropriate cooling air is calculated according to the load of the gas turbine. Select and use an air flow control orifice that has a through hole with a cross-sectional area that corresponds to the air flow rate. Therefore, unlike conventional methods, new adaptation is required each time the load on the gas turbine changes. Eliminates the need to manufacture gas turbine blades, improving manufacturing efficiency and significantly reducing It is possible to achieve a significant cost reduction, and it has an extremely excellent economical effect.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a gas turbine blade according to the invention.

FIG. 2 is a plan view of the air flow rate control orifice attachment portion in FIG. 1 as viewed from arrow A;

FIG. 3 is a plan view of an air flow rate control orifice mounting portion of another embodiment of the present invention as viewed from arrow A;

FIG. 4 is a longitudinal cross-sectional view of a conventional gas turbine blade.

[Explanation of symbols]

1 Gas turbine blade 2 Air inflow hole 3 First air passage 4 Second air passage 5 Downstream edge 6 Air outlet 7 Fins for promoting heat exchange 8 Heat exchange protrusion 9 Air flow control orifice

Claims (1)

[Scope of utility model registration request] [Claim 1] A gas turbine provided with a first air passage that pumps cooling air taken in from an air inflow hole at the bottom of the blade to the edge of the downstream surface of the blade, and a second air passage that pumps the cooling air to the upper surface of the blade. A gas turbine blade comprising an air flow rate control orifice attached to a recess provided at the inlet of the air inflow hole.