JPS60117008A - Burner - Google Patents

Abstract

PURPOSE:To enable uniform dispersion of fuel, to improve durability, and to reduce a manufacturing cost, by a method wherein an independent cylindrical prevaporizing and premixture chamber is disposed in parallel to a combustion chamber, and fuel-air premixture is inversed and is guided to the combustion chamber through a communicating chamber formed in a burner head. CONSTITUTION:An air A for combustion flowing along the outer peripheral part of a dilution cylinder 13, is guided to a premixing chamber 1 where the air for combustion is mixed with fuel F sprayed by injection of the fuel through injection by means of a main fuel injection valve 10 to produce fuel-air premixture M which flows in a communicating chamber 5. The fuel-air premixture forms a swirl flow around a flame stabilizing device 7, and in which case, the fuel-air premixture is further inversed and is guided to a combustion chamber 2 through an annular nozzle 8 for combustion. Further, the fuel-air premixture is diluted with a diluting air A' fed through a dilution hole 12 on the downstream side thereof, and the premixture, which forms diluted fuel-air mixture, continues to be burnt, and the produced high temperature gas is fed to a crawl inlet part 14.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a combustor, and more particularly to a counterflow can type combustor of a pre-evaporation and pre-mixing type.

As a conventional combustor of this type, although not shown in the drawings, for example, there is a combustor currently pending as Japanese Patent Application No. 3G-772797 by the present applicant. In the example in this application, an annular pre-evaporation premixing chamber is provided between the inner cylinder and the outer cylinder near the head of a counterflow can type combustor provided with an inner cylinder and an outer cylinder. It is configured to inject fuel from the main fuel injection valve into the mixing chamber to perform pre-evaporation and pre-mixing in the incoming air, and guide this through the head to the combustion chamber. Compared to the combustion method, this method provides a uniform supply of a lean air-fuel mixture and a stable flame, so it has the feature of significantly reducing NO emissions.

However, in such conventional combustors, the pre-evaporation and pre-mixing chamber is provided in the annular passage in the form of a counterflow can, so the size of the burner tube remains unchanged, and the current passage Due to its narrow radial width, it is difficult to uniformly distribute the fuel in the pre-evaporation premixing chamber provided here.

The purpose of the present invention is to solve these problems, and to achieve sufficient premixture, the overall length of the combustor can be reduced to the same level as a conventional diffusion combustor, it is highly durable, and the production table can be used in a manner similar to that of a conventional diffusion combustor. The object of the present invention is to provide a pre-evaporation and pre-mixing type combustor which is significantly cheaper.

In order to achieve this object, in the present invention, five independent cylindrical pre-evaporation premixing chambers are arranged in parallel with the combustion chamber, and the air in the annular passage is pre-evaporated from the same direction as in the counterflow type. The premixture obtained in the premixing chamber is introduced into the head combustion chamber through a communication chamber provided in the combustor head. Detailed description of the invention.

1 and 2 show an embodiment of the present invention, where / is a cylindrical pre-evaporation premixing chamber, C is a combustion chamber, and these premixing chambers L and combustion are arranged in parallel. In this example, the chambers are molded as an integral molded block J that also serves as heat insulation, using castable or machinable heat insulation material. The block 3 is separated into the head casing 371 side and the combustion chamber casing dam B side, and the blocks 3 are molded into one body when the casing dam is assembled, and each block 3 is attached with adhesive (primer) or the like. Casing +
Fix it to the walls of A and +B.

S is a communication chamber formed in the block 3 on the side of the casing 9A, and A is a buckle plate fitted into the top of the block 3 on the side of the combustion chamber casing 11B and held between both blocks 3. When this baffle plate 6 defines a space between the communication chamber S and the combustion chamber 7, the baffle plate 6 and the flame stabilizer 7 form an annular nozzle to the combustion chamber 7.

? Align the center of the flame holder 7 with the head casing 4.
(This is the auxiliary fuel injection valve that is removably inserted from the outside of A, lθ is the main fuel injection valve that is inserted from the outside of the casing <cH into the premixing chamber l, and l/ is sent to the combustion chamber This is an ignition lamp that ignites the premixture M.

Further, a dilution cylinder 13 having a dilution hole / is fitted on the downstream side of the cylindrical combustion chamber / in the block 3 , and a scroll inlet / / is further downstream of the dilution cylinder / 3 . &
are integrally molded.

Next, to describe the combustion operation in the combustor configured in this way, the combustion air A flowing in through the outer peripheral part KG of the dilution tube IS is first led to the premixing chamber I, where it is connected to the main fuel injection valve. Mixed with fuel F atomized by injection from 10 [7
, it becomes a premixture M and is guided to the communication chamber S.

Thus, from the top of the premixing chamber/to the communication chamber 5.

As shown in Figure 2, since the premixture M is introduced from the tangential direction, the premixture N becomes a swirling flow around the flame stabilizer 7, and is further reversed here. The premixture is guided from the annular nozzle g to the combustion chamber. The thus sufficiently vaporized premixture M is combusted in the combustion chamber, and further downstream, dilution air A' is supplied from the dilution hole /2.
The resulting high-temperature gas is diluted by the gas mixture and continues to burn as a lean mixture, and the resulting hot gas is sent to the scroll.

As mentioned above, in the combustor of this example, the combustion chamber, premixing chamber, etc. are made of integral heat insulating material, so there is no need to arrange the special combustion tube and its heat insulating material as in the conventional case. Further, since the premixing chamber l is formed in a cylindrical shape, a uniform premixture M can be easily generated due to the uniform diffusion distribution of the fuel F.

In addition, since the baffle plate 6 and flame stabilizer 7 are configured to be detachable as separate parts, the required machining precision and heat resistance of these parts can be independently selected and combined. be able to.

Although the auxiliary injection valve g is not essential for the pre-evaporation premix combustion system, it is used during startup and sudden acceleration.

Furthermore, by using the auxiliary injection valve g as an aid during times of high load, etc., there is an effect that the combustor, which is subject to such load fluctuations, can maintain a wide range of operating performance.

As explained above, according to the present invention, an independent cylindrical premixing chamber for pre-evaporating and premixing atomized fuel;
The combustion chamber for combusting the premixture is arranged in parallel, and a communication chamber for guiding the premixture to the combustion chamber is provided between the top of the combustion chamber and the top of the premixing chamber. The premixture is reversed in the communication chamber and guided to the combustion chamber.

These premixing chambers, combustion chambers, and communication chambers are each made of integral heat insulating material, making it possible to create an internal combustion tube similar to that used in conventional preevaporation and premixing type combustors. In addition, since the combustion chamber is connected to the dilution cylinder that is integrated with the flow path connected to the scroll inlet, the number of parts is reduced and assembly is easy, and the overall length of the combustor is shortened. It is only as long as a conventional diffusion combustor,
Not only is it highly durable, but its manufacturing cost is also extremely low.

Further, by forming the premixing chamber into an independent cylindrical shape, the fuel can be uniformly diffused and distributed, and an ideal premixed gas can be obtained. Furthermore, by using an auxiliary injection valve in combination, it is possible to maintain excellent followability against severe load changes* such as during J start or sudden acceleration, and a wide range of operating performance can be achieved.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of the configuration of the combustor of the present invention; FIG. 2 is a sectional view taken along the line B--B in FIG. 1. l... premixing chamber, a... combustion chamber, 3...Block, Hiroshi, DaA, lIB...Casing, S...Communication room, 6... baffle board, 7...Flame holder, g... annular nozzle, t...auxiliary fuel injection valve, 10... Main fuel injection valve, l/... No ignition, /2... dilution hole, 13... Dilution cylinder. /44...Scroll entrance section. 1st 1 Figure 2 figure

Claims (1)

[Scope of Claims] 1) An independent cylindrical premixing chamber that performs pre-evaporation and premixing of fuel, a combustion chamber that is arranged in parallel with the premixing chamber and combusts the premixed mixture, and A combustor according to claim 1, further comprising a communication chamber for reversing the flow of the obtained premixture and guiding it to the combustion chamber. The mixing chamber and the combustion chamber are integrally formed with a heat insulating material,
5. A combustor characterized in that the communication chamber is formed separately from the heat insulating material, and the communication chamber is detachably attached to the premixing chamber and the combustion chamber.