JPS6235001A - Gas turbine air cooled blade - Google Patents

Abstract

PURPOSE:To maintain the cooling efficiency good, by making the longitudinal length of each of slits of an insert, to be longer than the lateral length of the top of each of fins formed on the inner wall-surface of the outer layer of a blade. CONSTITUTION:Fins 9 are formed side by side, on the inner wall-surface of the outer layer 6 of a blade, and an insert 8 is set on the inside of these fins 9. The longitudinal length of each of slits 13 of the insert 8 is made to be longer than the lateral length at the top of each of the fins 9. Even if the tops of the fins 9 are placed in the slits 13 respectively, as an error is made when the blade is processed or assembled, openings are formed at the tops of the fins 9, and cooling air is guided to flow out. In this way, the cooling efficiency can be maintained good.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a gas turbine air cooling blade, and particularly relates to a gas turbine air cooling blade.
An insert with a large number of holes is installed in the Jll.
The cooling air flowing out from this insert cools the body.
Involved in internal air-cooled gas turbine IJI problems.

[Technical background of the invention...]

3. The gas turbine system is shown in Figure 4. In FIG. 4, the air 1 sucked in is compressed to 71 degrees by a compressor 2 and sent to a combustor 3. Fuel 4 is supplied to the combustor 3, and the fuel 4 generated by combustion enters the gas turbine 5, collides with turbine blades, and expands, thereby converting thermal energy into rotational energy of the turbine to generate power.

Since the combustion gas exiting the combustor 3 has a high temperature of 1000° C. or more, the turbine blades exposed to the high temperature gas need to be cooled with cooling air. The air for this purpose is provided by the discharge of the compressor 2 or the bleed air from an intermediate stage of the compressor 2. In particular, the turbine first stage static W is exposed to the most severe temperature conditions because the high-temperature combustion gas collides with it first, so an insert-type cooling W with excellent cooling effect is used for this blade. .

The structure of the insert type cooling W is shown in Figures 5 and 6. In this insert 1 type cooling vXJ, an inner 8 in which a large number of circular holes 7 are formed inside the blade skin 6 is arranged at a predetermined distance from the inner wall surface of the blade skin 6. Further, a large number of fins 9 are arranged in parallel on the inner wall surface of the blade skin 6 at predetermined intervals to increase the heat transfer area and improve the cold 7J1 performance.

Cooling air A flows from the central outer periphery (upper part in the figure) to the wing skin 6.
It is introduced into the inside of the insert 8 disposed therein, and collides with the inner surface of the leg skin 6 through a number of holes 7 formed in the insert 8. The cooling air that has collided with the inner surface of the wing skin 6 passes through the gap between the fins 9 and flows to the rear of the wing (on the right side in the figure) while performing forced convection cooling (impingement cooling), and some of the air is formed on the wing skin 6. The remaining gas flows through the gap between the bin fins 11 formed on the outer circumferential surface of the outer skin 6, cooling the blade, and merges with the mainstream gas from the 412 end 12 of the blade.

[Problems with background technology]

In such a gas turbine air-cooled blade, under normal conditions, the fins 9 provided on the inner wall surface of the blade skin 6 and the holes formed in the inserter 1-8 are in a positional relationship as shown in FIG. Yes, the cooling air has a specified flow h′! It passes through the gap between the fins 9 and performs cooling 1 of the blade.

However, if the hole 7 of the insert 8 is not formed at the specified position due to the manufacturing rA difference during the punching process, the position of the fin 9 installed on the blade skin 6 and the method 1 when manufacturing the blade skin 6 by precision casting may vary. If an error occurs, or if an assembly error occurs when fixing the insert 8 to the wing skin 6, the hole 7 is formed in the inner 8 as shown in FIG. It becomes blocked and prevents cooling air from flowing out. As a result, the blades may not be sufficiently cooled, leading to damage to the blades.

[Purpose of the invention]

The present invention provides the above-mentioned insert type gas turbine cooling r
An object of the present invention is to provide a gas turbine air-cooled blade that can prevent deterioration in blade cooling performance due to errors during processing or assembly of JI I.

[Summary of the invention]

The gas turbine cooling blade of the present invention is a gas turbine air-cooled hIX equipped with a blade skin in which a large number of fins are provided on the inner wall surface, and an insert that is disposed within the blade skin and in which a large number of holes are formed. , the hole formed in the insert is formed of a slit, and the length of the long side of the slit is longer than the length of the fin top in the width direction.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 shows the structure of an insert according to the present invention.

A large number of rectangular slits 13 are formed in this insert 8 at predetermined intervals. The opening area of the slit 13 determines the cooling air flow rate, so it is set by calculating the flow rate coefficient depending on the slit shape. The length in the width direction of the top of the fin 9 is slightly longer than that of the top of the fin 9.

In a gas turbine air-cooled blade with such an inner 8 disposed inside, if there are no errors during blade processing or assembly, the slit 13 will be blocked by the top of the fin 9 as shown in FIG. The desired blade cooling performance can be obtained. Also, if an error occurs during processing or assembly of W and the top of the fin is completely located within the slit 13 formed in the inlet 8 as shown in FIG. Since the length is longer than the length in the width direction of the top of the fin 9, openings are formed on both sides of the top of the fin 9 in the width direction, and cooling air flows out from this opening. Furthermore, it goes without saying that when a portion of the top of the fin 9 closes the slit 13, an opening is formed through which the cooling air flows out.

In the present invention, there is no restriction on the shape of the slit formed in the insert 8, as long as the length on the long side of the slit is slightly longer than the widthwise length of the top of the fin 9. It may be a shaped slit. Further, the slits formed in the inner 8 may be arranged in parallel at predetermined intervals, or may be arranged in a staggered manner.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to form a slit in the inserter 1 whose long side is longer than the widthwise length of the top of the fin provided on the wing skin, so that errors in processing or assembling the wing can be avoided. Since the fin tops do not completely block the slits and an opening is formed through which cooling air always flows out, cooling performance for the blades can be maintained at all times.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention, FIG. 2 is a sectional view showing the normal arrangement of the insert and fin shown in FIG. 1, and FIG. 3 is a diagram not shown in FIG. 1. Fig. 4 is a system diagram of a gas turbine; Fig. 5 is a cross-sectional diagram of a cooling blade using insert type 1; Fig. 6 is a cross-sectional diagram showing an insert type cooling blade. Figure 7 is a cross-sectional view showing the normal arrangement of the conventional insert and fin, and Figure 8 is a cross-sectional view of the conventional insert and fin, showing the normal arrangement of the fin. It is. 7...Air, 2...Compressor, 3...Combustor, 4...
...Fuel, 5...Gas turbine, 6...Bokurin, 7
... circular shape with a hole), 8 ... inserter], 9 ...
Fin, 10... Hole, 11... Bin fin, 13.
··slit. Applicant's agent Kihaya Hatano 4 illustrations 5 times

Claims (1)

[Claims] A gas turbine air-cooled blade comprising a blade skin having a large number of fins on an inner wall surface, and an insert disposed within the blade skin and having a large number of holes formed therein, wherein the holes formed in the insert are A gas turbine air cooling blade comprising a slit, the length of the long side of the slit being longer than the length of the fin top in the width direction.