JPS60126521A - Fuel injection valve of combustor for gas turbine - Google Patents

Abstract

PURPOSE:To enable always a superior atomization and making fine particles to be performed without being influenced by a flow rate of fuel and a flow speed of air by a method wherein fuel in injected into an air gallery through injection nozzles. CONSTITUTION:A fuel gallery 10 in a distributor 9 is formed with a plurality of injection nozzles 25 to be opened in a direction crossing at a right angle with a central axis of an air gallery 11 having a circular cross section. The air gallery 11 is formed with injection nozzles 28 opened at both sides facing to the flow of the air A in the distributor 9, the nozzles being crossed at a right angle with the injection nozzle 25. The fuel in the fuel gallery 10 is injected into the air gallery 11 through the injection nozzle 25, it is mixed in advance with the air and uniformly atomized over an entire air main flow pipe 7 through several injection nozzles 28. With this arrangement, a characteristic in atomization of fuel and making fine particles of fuel can be kept well without being affected by a flow speed of the air A and the flow rate of the fuel.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) This invention relates to improvements in fuel injection valves for gas turbine combustors.

(Background technology) In order to achieve better combustion in the combustor and achieve a 4T nap, premixing is used in which fuel is sprayed toward the air from the compressor, mixed well, and then flows into the combustion tube. A gas turbine combustor of the following type is known.

As a fuel 111 injection valve used in such a combustor,
For example, the one shown in Figure 1 was filed in a patent application filed in 1973 by the present applicant.
No. 8-174992.

To explain this, a streamlined center core 2 that follows the flow of incoming air is disposed on the center line of the main air pipe 1 in a combustion cylinder (not shown).

Reference numeral 3 denotes a fuel passage that guides fuel into the center core 2. A plurality of fuel supply pipes 4 are connected to this fuel passage 3 and extend radially from the outside of the center core 2 toward the combustion cylinder side. A fuel injection nozzle 5 is interposed.

According to this, fuel is uniformly sprayed over substantially the entire area of the main air pipe 1 into the inflow air A from the compressor through the injection nozzles 5 of each fuel supply pipe 4 protruding from the center core 2, resulting in a uniform fuel concentration distribution. The mixture becomes a mixture and is supplied to the combustion tube.

Furthermore, since the center core 2 has a streamlined shape, there is no possibility that a circulating flow region will occur downstream of the center core 2, and therefore, there is no need to worry about the air-fuel mixture remaining downstream of the combustion slant supply whistle 4 and causing self-ignition. be done.

However, in such an injection valve, the fuel is directly sprayed into the incoming air A through the injection nozzle 5 with a fuel supply rate of 4, so that the flow velocity of the incoming air Δ is sufficient. If this is not possible, or if the fuel flow rate is reduced,
There is a problem that the atomization and atomization characteristics of the fuel deteriorate.

(Purpose of the Invention) This invention was made by paying attention to such problems, and it is possible to always obtain good atomization and atomization characteristics without being affected by the fuel flow rate or air flow rate. The purpose is to provide fuel injection valves.

(Structure and operation of the invention) Therefore, the present invention provides a combustor for a gas turbine in which fuel is sprayed into air flowing in from a compressor, and this air-fuel mixture is supplied to a combustion tube and combusted. A streamlined center core is provided, and distributors with multiple peeling cross sections are arranged radially around its outer periphery, and each distributor has a fuel gear to supply fuel and a fuel gear to supply air under pressure. An air gear is formed, and a fuel injection nozzle that opens the fuel gear V into the air gear and a spray nozzle that opens the air gear to the outside of the distributor are formed.

Therefore, the fuel injected into the air gear through the injection nozzle mixes with the air in the air gear and is vigorously injected from the spray hole into the incoming air from the compressor.
The atomization and atomization characteristics of the fuel are not significantly affected by the flow velocity of the incoming air or the flow rate of the fuel, and are always maintained at a good level.

(Example) Hereinafter, this invention will be explained according to the example shown in FIG. 2.3.

In the figure, 6 is a casing of a combustor, 7 is a passage for air to be fed under pressure from the compressor, and a combustion tube (not shown) is disposed downstream of this passage.

The main air pipe 7 is provided with a teardrop-shaped streamlined center core 8 on its center line, and on the outer periphery of the center core 8 there are a plurality of distribution sections having peeled cross sections with low fluid resistance as shown in FIG. The vessels 9 are provided radially protrudingly at equal intervals.

Inside the distributor 9, in addition to a fuel gearbox 10, an air gearbox 11 is formed.

The center core 8 is divided into a head 12 and a tail 13.
A chamber 14 that communicates with all the fuel gears 10 and a chamber 15 that communicates with all the air gears 11 are formed inside the fuel tank 3 . The head 12 is screwed onto the tail 13, and the machined hole 16 between the communication holes 14 and 15 is closed by the protrusion 17 of the head 12.
○Ring 18 ensures oil tightness.

At least one of the plurality of distributors 9 is connected to a stay 19, and the fuel gear 10 of the distributor 9 is connected to the stay 19.
A fuel passage 20 that communicates with the air gear and an air passage 21 that also communicates with the air gear gallery 11 are formed, and the fuel passage 20
The air passage 21 is connected to a fuel and air supply source (not shown) by piping.

The stay 19 is attached to the mounting opening 2 formed in the casing 6.
2, the center core 8 and distributor 9 are inserted into the main air pipe 7, and then fixed to the casing 6 via the flange 23 so as to airtightly close the mounting opening 22.

2/4 indicates a gasket interposed between the flange 23 and the casing 6.

In the distributor 9, a plurality of injection nozzles 25 (pores) are formed in the fuel gear 10 and the air gear 11 having a circular cross section in a direction perpendicular to the central axis thereof.

Reference numeral 26 denotes a machined hole that was used when drilling the small hole 25, and this machined hole 26 is firmly closed with a plug 27.

On the other hand, spray nozzles 2B are formed in the air gear gallery 11 to be perpendicular to the spray nozzles 25, and are open on both sides facing the flow of the air A of the distributor 9.

With this configuration, fuel from the fuel supply source passes through the passage 20 of the stay 19, enters the fuel gearbox 10 of the distributor 9, is led to the communication line 1/1 of the center core 8, and is connected to the fuel gearbox of each distributor 9. 10.

Then, as shown in FIG. 3, the fuel in the fuel gear 10 is injected into the air gear 11 through the injection nozzle 25, becomes a fuel jet, collides with the inner peripheral wall surface of the air gear 11, and moves upward and downward. The flow is divided to form and cover the fuel film 29.

-h, air from the air supply source enters the air gear 11 of the distributor 9 through the passage 21 of the stay 19, is supplied to the air gear 11 through the communication chamber 5 of the center core 8, and is ejected from the spray nozzle 28. However, at this time, the above fuel film 29
is atomized by the shearing action of the air, and is vigorously sprayed toward the air A flowing into the main air pipe 7.

The fuel in the fuel gear 10 is injected into the injection nozzle 2 like a mouth.
5 into the air gear gallery 11, premixed with air, and evenly sprayed over the entire area of the main air pipe 7 by a large number of spray nozzles 28, so that the atomization characteristics of the fuel are similar to that of the air A. It can be maintained well without being affected by the flow rate of the fuel or the flow rate of the fuel, thus promoting the mixing of the fuel and the air A, and also without causing swirling flow etc. using a swirler etc. An extremely uniform air-fuel mixture from the fuel concentration valve 4i can be supplied to the combustion cylinder. Furthermore, as the atomization and atomization characteristics of the fuel are improved, the width of the fuel flow rate, the so-called turndown ratio, can be greatly reduced.

FIG. 4 shows another embodiment, in which the center summer area 8A
The head 12A is a stay 19A extending parallel to the flow of the incoming air A. The stay 19A is composed of a double pipe, and the fuel passage 2O guides fuel from the fuel supply source through the communication chamber 14 to the fuel gear gallery 10 of each distributor 9 through the inner pipe 30.
A is formed, and an annular space formed by the inner tube 30 and the outer tube 31 communicates air from the air supply source to the chamber 15.
An air passage 2 leading to the air gear 11 of the distributor 9 via
It is 1A.

Since the head 12A of the center core 8A is formed on the stay 19A, the fuel gear 10 and air gear 11 of all the distributors 9 are formed in a hole-like shape. is omitted.

According to this, there is also an advantage that the distribution characteristics of the fuel and air to the fuel gear gallery 10 and the air gear gallery 11 of the distributor 9 are improved compared to the embodiment described above.

In each of the above embodiments, the air gear 11 is arranged at the front end of the blade of the distributor 9, and the fuel gear 10 is arranged at the rear end. That is, the fuel gear 10 may be arranged closer to the front end of the blade of the distributor 9 than the air gear 11.

Furthermore, if steam is fed into the air gear 11 of the distributor 9 instead of air, the amount of NOx and smoke generated during combustion can be reduced.

(Effects of the Invention) In summary, according to this invention, the atomization and atomization characteristics of the fuel are not affected much by the flow rate of the fuel or the flow rate of the air flowing into the compressor, and are always maintained at a good level. The effect is that an extremely uniform premixture can be supplied to the combustion cylinder even under operating conditions.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a main part of a conventional example, Fig. 2 is a sectional view of a main part showing an embodiment of the present invention, Fig. 3 is a sectional view taken along the line B-B, and Fig. 4 shows another embodiment. It is a sectional view of the main part. 7... Main air pipe, 8,9A... Center core, 9.
...Distributor, 10...Fuel gear, 11...Air gear, 25...Injection nozzle, 26...Spray nozzle. Patent applicant Nissan Motor Co., Ltd. Figure 1 Figure 2

Claims (1)

[Claims] In a gas turbine combustor that sprays fuel into the inflowing air from a compressor and supplies this air-fuel mixture to the combustion tube for combustion, a streamlined hinter core that follows the flow of the inflowing air is installed. Distributors each having a plurality of airfoil-shaped surfaces are arranged radially in the interior of each distributor, forming a fuel gear to which fuel is supplied and an air gear to which air is fed under pressure. - A fuel injection valve for a combustor for a gas turbine, characterized in that a fuel injection nozzle that opens a V-rally into an air gear rary, and a spray nozzle that connects the air V-rally to the outside of a distributor are formed.