JPH0559323B2 - - Google Patents

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 being filed by the applicant as Japanese Patent Application No. 172,797/1983. 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 having an inner cylinder and an outer cylinder. It is constructed so that fuel is injected into the mixing chamber from the main fuel injection valve to perform pre-evaporation and pre-mixing in the incoming air, and this is guided from the head to the combustion chamber. Compared to the diffusion combustion method, this method provides a uniform supply of a lean mixture and a stable flame, so it has the feature of significantly reducing NO _x emissions.

However, in such conventional combustors, the pre-evaporation and premixing chamber is provided in the backflow can type annular passage, so the size of the combustion tube remains unchanged and the annular passage itself Due to the narrow radial width, it is difficult to achieve a uniform distribution of fuel in the pre-evaporation premixing chamber provided here.

The purpose of the present invention is to focus on such problems,
To provide a pre-evaporation and pre-mixing type combustor which can obtain sufficient pre-mixture, has the overall length of the combustor comparable to that of a conventional diffusion combustor, is highly durable, and is significantly cheaper to manufacture than conventional ones. There is a particular thing.

In order to achieve such an object, the present invention includes a cylindrical combustion chamber that burns a premixture, and a cylindrical combustion chamber that is arranged in parallel with the combustion chamber with different axes and has a cross-sectional area smaller than the cross-sectional area of the combustion chamber. A combustion chamber casing is provided with an independent cylindrical premixing chamber for pre-evaporation and premixing, and a head casing is detachably provided at one end of the combustion chamber casing. At least one of the combustion chamber casing and the head casing is configured to reverse the flow of the premixture and to introduce a communication chamber into the cylindrical combustion chamber in a tangential direction thereof at a joint between the combustion chamber casing and the head casing. It is characterized by the fact that it is provided in

The present invention will be explained in detail below based on the drawings.

FIG. 1 and FIG. 2 show an embodiment of the present invention,
Here, 1 is a cylindrical pre-evaporation premixing chamber, 2 is a cylindrical combustion chamber with a larger cross-sectional area than the premixing chamber 1, and these premixing chambers 1 and combustion chambers 2, which are arranged in parallel, In this example, a castable or machinable heat insulating material is used to form the integral molded block 3 which also serves as a heat insulator. The block 3 is separated into the head casing 4A side and the combustion chamber casing 4B side, and when the casing 4 is assembled, the blocks 3 are molded integrally, and each block 3 is attached with adhesive (primer) or the like. and fix it to the wall surfaces of casings 4A and 4B.

5 is a communication chamber formed in the block 3 on the side of the head casing 4A, and 6 is a communication chamber formed on the side of the combustion chamber casing 4B.
This baffle plate is fitted into the top of the side block 3 and held between both blocks 3, and this buffle plate 6 defines the space between the communication chamber 5 and the combustion chamber 2, and also separates the buffle plate 6 from the combustion chamber 2. The flame stabilizer 7 forms an annular nozzle 8 into the combustion chamber 2 .

9 is an auxiliary fuel injection valve that is removably inserted from the outside of the head casing 4A with its center aligned with the flame stabilizer 7, and 10 is a main fuel injection valve that is inserted into the premixing chamber 1 from the outside of the casing 4B. , and 11 more
is an ignition sparkler that ignites the premixture M sent to the combustion chamber 2.

Further, in the block 3, a dilution cylinder 13 provided with a dilution hole 12 is provided on the downstream side of the cylindrical combustion chamber 2.
A scroll inlet portion 14 is integrally formed further downstream of the dilution cylinder 13.

Next, to describe the combustion operation in the combustor configured as described above, the combustion air A flowing in along the outer circumference of the dilution cylinder 13 is first guided to the premixing chamber 1, where it is connected to the main fuel injection valve 10. It mixes with the fuel F atomized by the injection from the air, becomes a premixture M, and is guided to the communication chamber 5.

Since the premixture M is introduced from the top of the premixing chamber 1 into the communication chamber 5 from the tangential direction as shown in FIG. The premixed air becomes a swirling flow around the . The premixture M thus sufficiently vaporized is combusted in the combustion chamber 2, and further diluted by the dilution air A' supplied from the dilution hole 12 on the downstream side, and combustion continues as a lean mixture. The resulting hot gas is sent to the scroll.

As mentioned above, in the combustor of this example, the combustion chamber 2, premixing chamber 1, etc. are formed of a single piece of heat insulating material, so there is no need to arrange special combustion areas and their heat insulating materials as in the past. Moreover, since the premixing chamber 1 is formed in a cylindrical shape, a uniform premixture M can be generated by uniform diffusion distribution of the fuel F.
It becomes easy to generate.

In addition, since the full plate 6 and the 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 9 is not essential for the pre-evaporation and premix combustion system, the auxiliary injection valve 9 is used at startup, during load fluctuations, and even during high loads.
By using the combustor in combination as an auxiliary, it is possible to achieve the effect of maintaining a wider range of motion performance in the combustor.

As is clear from the above description, according to the present invention, there is provided a cylindrical combustion chamber in which a premixture is combusted; A combustion chamber casing in which an independent cylindrical premixing chamber for pre-evaporating and premixing fuel is formed, and a head casing detachably provided at one end of the combustion chamber casing, the premixing chamber The flow of the premixture obtained in step 1 is reversed, and a communication chamber is formed between the combustion chamber casing and the head casing at the joint between the combustion chamber casing and the head casing, and a communication chamber is formed to introduce the premixture into the cylindrical combustion chamber in the tangential direction thereof. Since the combustor is provided on at least one side of the combustor, sufficient premixture can be obtained, and the overall length of the combustor is only as long as a conventional diffusion combustor, which not only has excellent durability but also reduces manufacturing costs. It is also possible to obtain an extremely inexpensive combustor.

In addition, by making the premixing chamber independent and cylindrical, the fuel can be uniformly diffused and distributed.
An ideal premixture can be obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of the configuration of the combustor of the present invention, and FIG. 2 is a sectional view taken along the line BB in FIG. 1. DESCRIPTION OF SYMBOLS 1... Premixing chamber, 2... Combustion chamber, 3... Block, 4, 4A, 4B... Casing, 5... Communication chamber, 6... Buffle plate, 7... Flame stabilizer, 8... Annular Nozzle, 9... Auxiliary fuel injection valve, 10... Main fuel injection valve, 11... Ignition plug, 12... Dilution hole,
13... Dilution tube, 14... Scroll inlet section.

Claims (1)

[Claims] 1. A cylindrical combustion chamber for combusting a premixture, and pre-evaporation and premixing of fuel with a cross-sectional area smaller than the cross-sectional area of the combustion chamber, which is arranged in parallel with different axes from the combustion chamber. a combustion chamber casing in which an independent cylindrical premixing chamber is formed, and a head casing detachably provided at one end of the combustion chamber casing, the premixture obtained in the premixing chamber; A communication chamber is provided in at least one of the combustion chamber casing and the head casing at a joint between the combustion chamber casing and the head casing to reverse the flow of the combustion chamber and to introduce the cylindrical combustion chamber in a tangential direction thereof. Characteristic combustor.