JPS59231103A - Cooled blade of gas turbine - Google Patents

Abstract

PURPOSE:To contrive to improve the cooling performance of a blade by a structure wherein cooling medium pipes are fixed on the outer surface of blade base material with filling material and, after that, a covering layer made of sintered alloy is provided on said outer surface. CONSTITUTION:Cooling medium pipes 17 are arranged on the outer surface of blade base material 16 made of heat resisting metal and filling material 18 is filled between the pipes 17 in order to fix the pipes 17. Further, a covering layer 19 made of sintered alloy is provided on said outer surface. In this way, the pipes 17, which form the cooling layer, can be densely arranged side by side on the outer surface of the blade base material 16, and therefore the cooling performance of a blade can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a gas turbine cooling blade that allows a cooling medium to flow inside the turbine blade near its outer surface.

[Technical Background of the Invention and Problems Therewith] In general, gas turbines have many advantages over reciprocating engines, such as being smaller, lighter, and capable of producing large horsepower.

FIG. 1 is a diagram showing a schematic configuration of a normal gas turbine, in which guide vanes 3a and rotary vanes 3) are alternately arranged at one end of a shaft 2 rotatably provided in a cylindrical casing l. An axial flow type compressor 3 is provided in which the compressor 3 is arranged in the axial direction, and a power tarping is provided in the other end in which the rotor blades and stator blades are alternately arranged in the axial direction. A combustor is installed between the compressor 3 and the power turbine! is installed, the pressure inside the combustor j is increased with high-pressure air compressed by the compressor 3, and in this state fuel is injected and combusted,
The ultra-high-pressure, high-temperature gas generated by this combustion is guided to the power tarping and expanded to generate rotational power for the shaft.

By the way, in order to improve the efficiency of the gas turbine as described above, the most effective means is to increase the gas temperature at the inlet of the power tarping. but,
The permissible temperature of the metal material constituting the power tarping is generally about tro'c, and it is impossible to raise the gas temperature beyond this. Therefore, it is necessary to efficiently cool the members, especially the blades, constituting the power tarping that raises the gas temperature above the above-mentioned allowable temperature.

There are air cooling methods and liquid cooling methods as means for cooling the blades, but the folding method also has multiple refrigerant passages under the surface of the blade, and air and cooling liquid are circulated within these passages. There is.

However, in the air cooling system, when trying to raise the gas temperature, the amount of air required increases significantly, and the attached equipment also increases in capacity, and when the gas temperature exceeds a certain value, the overall efficiency decreases. There's a problem.

On the other hand, as shown in FIG. 2, in the liquid cooling system, cooling water is supplied from the cooling water supply port // provided in the blade root 10 to the manifold 13 formed inside the blade platform/a. The cooling water is supplied from the manifold /3 to a large number of cooling holes /4 (K) drilled inside the outer surface of the blade, and cools the blade base material /S by flowing it toward the blade tip. However, in this type of blade, it is necessary to drill cooling holes inside the blade base material, and not only is it difficult to do so, but there are also gaps between the cooling holes 74. There are problems such as variations in temperature distribution and difficulty in keeping the blade base material at a uniform temperature.

[Purpose of the invention]

In view of these points, the present invention is capable of improving the cooling performance of turbine blades exposed to high-temperature gas, is easy to manufacture, and can uniformize the temperature distribution of the blade base material.
The objective is to obtain gas turbine cooling blades with

(j) [Summary of the Invention] The present invention provides an outer surface K of a blade base material made of heat-resistant metal, and a large number of coolant conduction pipes extending Km from the root of the blade to the tip so as to cover the outer surface of the blade base material. At the same time, a powder filler with good thermal conductivity is filled and fixed between the coolant conduction pipes, and the outer surface of the blade is formed on the outer surface of the cooling layer consisting of the coolant conduction pipes and the filler. It is characterized in that layers made of sintered alloy are laminated.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to FIG. 3 and FIG.

In FIG. 3, the blade root 10 K U is connected to a cooling water supply port l formed in the blade platform l-, which communicates with the manifold/3VC, similar to the conventional turbine blade shown in FIG.
By the way, the blade base material 1 made of nickel-based heat-resistant metal is integrally formed with the blade platform 7.2.
A large number of coolant conduction pipes 1 having good thermal conductivity, such as pipes (4'), whose base ends communicate with the manifold i3 and extend toward the tips of the blades are disposed on the outer surface of the pipe 6.
7 are arranged so that they are almost in contact with each other, and the gap between each cooling medium conducting pipe/7 is filled with powdery material having a high melting point and good thermal conductivity, such as iron powder, carbon powder, graphite, etc. The cooling medium conduction pipe /7 is fixed to the outer surface of the blade base material /6 by the filling material, and a cooling layer is constituted by the cooling medium conduction pipe /7 and the filling material /g. . Further, on the outer surface of the cooling layer, a laminated material /9 made of a sintered alloy is layered to form the outer surface of the blade (Fig. 3).

As a result, the rotor on which the turbine blades are attached becomes hot.
When the drive is exposed to high-pressure gas, the cooling water that is the cooling medium introduced from the cooling water supply port
The coolant flows through the manifold/3 and through each cooling medium pipe/7 toward the tip of the blade, thereby cooling the blade base I/L, the laminated layer/Q, and the like. In other words, the blade base material /6 made of heat-resistant metal functions as a blade strength member, and in the cooling layer, the blade base material /l
and cooling of the coating r@/9 and absorption of the thermal stresses inherent therein.

Also a covering layer/? The main effect is as a heat shield.

〔Effect of the invention〕

Since the present invention is constructed as described above, the weight loss material and the hollow coating layer can be processed independently when manufacturing the same, and a pipe can be used for the part through which the cooling medium flows. Therefore, there is no need to perform complicated hole machining on the weight-reducing material itself as in the past, and the machining can be performed extremely easily. In addition, from the standpoint of cooling performance, it is possible to closely arrange the coolant conduction pipes that make up the cooling layer on the outer surface of the weight loss material, and it is possible to achieve a uniform temperature distribution over the entire blade surface, which increases the The base material can be kept at a uniform temperature, and the arrangement of the coolant passage pipes can also be changed in accordance with the temperature conditions of the blade surface. Furthermore, since a powdered filler is filled between the paulownia wood and the coating layer to fix the cooling medium conduction pipe, this filler causes deformation of the weight loss material, the conduction pipe, and the coating layer due to thermal stress. It has the advantage of being able to absorb heat and sufficiently withstand thermal stress.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram of a general gas turbine, Fig. 2 is a side view showing a partial cross section of a conventional water-cooled gas turbine blade,
FIG. 3 is a partially sectional side view of the gas turbine cooling blade of the present invention, and FIG. μ is a partially enlarged cross-sectional view of the gas turbine cooling blade of the present invention. 10... Root of the blade, //... Cooling water supply port, /3.
... Manifold P, /6... Weight loss material, /7... Cooling medium conduction hole, 7g... Filling material, /9... Covering layer.

Claims (1)

[Scope of Claims] / An outer surface K of a blade base material made of a heat-resistant metal, and a large number of cooling medium conduction pipes extending from the root of the blade to the tip so as to cover the outer surface of the blade base material, A powder filler with good thermal conductivity is filled and fixed between the coolant conduction pipes, and the outer surface of the cooling layer consisting of the coolant conduction pipes and the filler is made of a sintered alloy that forms the outer surface of the blade. A gas turbine cooling blade characterized by a layered layer. (h) The gas turbine cooling blade according to claim 1, wherein the cooling medium conducting pipe is made of a pipe with good thermal conductivity. 3. The gas turbine cooling blade according to claim 1, wherein the filler is made of a powdery substance with a high melting point and good thermal conductivity.