JPS58195711A - Cooling device for transition piece - Google Patents

Abstract

PURPOSE:To improve a cooling effect and a specific output efficiency of a high temperature gas turbine, by a method wherein a cooling pipe is installed around the transition piece of the gas turbine, and a cooling air is jetted against the local high temperature part of said piece through the nozzle of the cooling pipe. CONSTITUTION:In a high temperature gas turbine, fuel through a fuel feed pipe 7 is burned by a burner 4, and combustion gas 8 is introduced to the turbine 2 through a transition piece 3 to rotate the turbine 2 and drive a load device 9. In which case, the air extracted from a final stage of a compressor 1 is cooled by a cooler 5 to boost it into a pressure higher than an atmosphere pressure 17 by means of an atomizing air compressor 6. After the air is fed to a cooling pipe 12 through an air feed pipe 11 through a flow rate regulating orifice 10, a cooling air 16 is blown through a nozzle 13 against a high temperature part 15 of the transition piece 3 to cool the metal of said piece 3. This permits the effective cooling of said piece 3 and enables the improvement of the specific output efficiency of the gas turbine 2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a two-piece cooling system for a gas turbine.
& Direct related. Sometimes it relates to a cooling device that cools a transition piece of a high-temperature gas turbine.

Generally, as shown in FIG. 1, a high-temperature gas turbine is constructed by introducing fuel from a fuel supply pipe 7 and combusting it in a combustor 4, and passing the generated high-temperature and high-pressure combustion gas 8 through a transition piece 3t. to the turbine 2.
is rotated to drive the load device 9. (1 in the figure is a compressor, and the air compressed here is cooled by cooling water W in a cooling device 5, and is sprayed into an air compressor 6.
is introduced into the combustor 4 as combustion air. W is cooling water. ) However, in the prior art, the transition piece 3 is not provided with any particular cooling means, and this often causes problems.

That is, for example, in a transition piece of a gas turbine having a single-cylinder combustor, the structure becomes complicated because the flow is distributed evenly to the first-stage stationary blades all around the circumference.

For this reason, there is a considerable temperature difference between each part of the transition piece, so if the temperature of the combustion gas is raised, the metal ljA degree may locally exceed the limit temperature, and unless it is cooled, it will be intermittent.

On the other hand, in order to measure the specific output efficiency of the gas turbine,
It is essential to raise the combustion temperature of gas turbines.

However, in the conventional transition piece, since the load is not cooled as described above, very high temperature gas cannot pass through the transition piece, and in the end, there is no choice but to keep the combustion gas temperature low, which reduces the efficiency of the turbine. niC
The work limit was almost reached. If we wanted to increase the fI and f18 without cooling, it would be necessary to make it from a special heat-resistant material, which would require a large amount of money and time to develop. will occur.

The object of the invention is to solve the above-mentioned problems by cooling the gas turbine, thereby achieving the specific output efficiency of the gas turbine, and at the same time, the cooling can be done reliably and stably, and at low cost. Transition 7 that can be obtained in
We will provide peace cooling equipment.

9 [The present invention is provided with a nozzle in the vicinity of the nozzle/piece, and the cooling air β is flowed out from the nozzle into the cooling pipe (t). ′:
By attaching 11lk to 1 and lowering the metal temperature of the transition piece, the above objective can be achieved without the need to make any particular changes to the shape of the transition piece.

Before explaining one embodiment of the present invention with reference to the figures below, the background to the present invention will be described. In a conventional gas turbine as shown in the schematic system diagram in Figure 's1,
Based on the experiments conducted so far, in order to increase the combustion gas temperature of the gas turbine 2, the metal II of the transition piece 3
It turns out that it is best to keep the A degree below the limit.

Therefore, in the present invention, in order to solve the above-mentioned problem,
As illustrated in FIGS. 2 and 3, the conventional orifice 10. Air introduction pipe 11. Cooling pipe 12t - This is an additional configuration.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. The structure of this example is shown schematically in FIG. 2, and in FIG. That is, as shown in the figure, in this example, an orifice 10°1 is branched from the atomizing air compressor 6 and attached to a pipe 7ji□i.Discharge casing 14': An air introduction pipe 11. It consists of a nozzle 13 provided in an annular cooling pipe 12 attached around the transition piece 3. The formation of the nozzle 13 in the cooling pipe 12 is as shown in FIG.

Cooling using this device involves cooling the air extracted from the first and final stage of the compressor 1 with the cooler 5, and then using the spray air compressor 6.
The pressure is raised above the atmospheric pressure 17, and the 9 air is introduced into the cooling pipe 12 by the lightning 11 through the flow rate adjustment orifice 10t, and the high temperature s15 of the transition piece 3 is passed through the nozzle 13.
Spray 16 tons of cooling air onto transition piece 3.
Cool the metal. The flow rate of cooling air 16 is adjusted by orifice 10. Specifically, the nozzle is designed to inject cooling air into the part to be cooled according to the temperature distribution of the 8 parts of high temperature @15.

According to this embodiment, as shown in the JGS diagram, the temperature of the transition piece metal can be lowered by approximately 2000 t, and the metal limit temperature (approximately 850 C).

In practice, when used at about 75 parts 0), the combustion gas temperature can be increased by 240C.

Therefore, as shown in FIG. 6, even if the gas turbine has the same size and shape, the output and efficiency can be greatly improved compared to the conventional gas turbine.

[Brief explanation of the drawing]

Figure 1 shows a schematic diagram of a conventional gas turbine system, Figure 2
3 is a diagram showing an outline of a gas turbine system according to an embodiment of the present invention, FIG. 3 is a diagram showing a state in which a cooling pipe is incorporated into the gas turbine in this example, and FIG. FIG. 5 is a diagram showing the details of the nozzle part, FIG. 5 is a diagram showing the relationship between metal temperature and combustion gas temperature, and FIG. 46 is a diagram showing the cycle calculation of the gas turbine. 2... Gas turbine, 3... Transition piece, 12... Cooling pipe, 13... Nozzle. Agent Patent Attorney Masami Akimoto #10 2 territories 63 days 4-eyes 15'' Dona to Tatsuryoku Su fLR ('C) $Z Mehijo (KWhp/s)

Claims (1)

[Claims] 1. By providing a cooling pipe around the transition piece of a high-temperature gas turbine, guiding cooling air through this cooling pipe, and letting the cooling air flow out from a nozzle provided in the cooling pipe, the metal temperature of the transition piece can be further reduced. A two-piece 7-piece cooling system characterized by having a configuration in which parts are locally cooled.