JP3087458B2 - Spray combustor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spray combustor for injecting fuel from a fuel injection valve into a combustion cylinder to perform combustion.

[0002]

2. Description of the Related Art As a conventional spray combustor, there is a combustor shown in FIG. This combustor sends the primary air A1 to the combustion chamber N in the combustion cylinder 7 through the cut-and-raised area 80b of the swirl vane 80 as a flame stabilizer and the center hole 80d.
The fuel sprayed from is supplied through the center hole 80d of the flame stabilizer. However, in this conventional configuration, when the fuel spray amount is reduced, the primary air
The amount of A1 had to be reduced, and the swirling flow downstream of the flame stabilizer became weak. As a result, the stability of the flame deteriorated, and there was a problem that the blow-off easily occurred. Accordingly, the present applicant has proposed a spray combustor shown in FIG. 13 in Japanese Patent Application No. 2-319239. In this combustor, the air sent through the center hole 80d of the flame stabilizer and the air sent through the swirler vane 80, which is the main body of the flame stabilizer, are completely independently separated by the primary air cylinder 2. Supply, thereby increasing the amount of air sent through the swirl vanes 80 so that it can be supplied to the combustion chamber N in the combustion cylinder 7, and another air is supplied to the combustion cylinder 7.
Is sent into the combustion chamber N as separate air from the hole on the inner peripheral surface of
The fuel sprayed from the fuel injection valve 11 is supplied to the center hole 80 of the flame stabilizer.
The air is supplied to the combustion chamber N together with the air through d. FIGS. 14A and 14B are detailed views of the vicinity of a flame stabilizer of a conventional spray combustor, wherein FIG. 14A is a front view and FIG. 14B is a sectional view. This example is different from the example of Japanese Patent Application No. 2-319239 only in that the shape of the swirling blade 80 is slightly different. The same applies to this example and the two examples described above, but the air passing through the swirling blade 80 has a configuration in which a part of the airflow A5 flows radially outward of the swirling blade 80.

[0003]

However, in each of the above-described conventional examples, a part of the airflow A5 passing through the swirling blade 80 flows radially outside the swirling blade 80. A6 and the airflow A7 inward in the radial direction are reduced, the swirling flow is weakened, and there is a problem that a smooth swirling flow cannot be performed. In addition, this is a factor that creates an airflow stagnation region on the outer peripheral side of the swirling blade 80. Further, in the combustor having the configuration shown in FIGS. 13 and 14, when the fuel flow rate is increased, the air current is strongly swirled, so that the fuel spray spreads immediately from the vicinity of the exit of the center hole 80d, and depending on conditions, There is a drawback that the tendency that the swirling blade 80 is wet or soot adheres to the blade 80 is increased. On the other hand, when the fuel flow rate is reduced, the swirling air gradually does not contribute to combustion,
For example, the generation of soot was increased, and there was a disadvantage that the flame holding property and the combustibility were not improved.

[0004] Accordingly, an object of the present invention is to solve the above-mentioned drawbacks of the conventional spray combustor, to provide a more stable flame, and to provide a spray combustor exhibiting good combustion characteristics.

[0005]

In order to solve the above-mentioned object, a spray combustor according to the present invention comprises a swirler having a center hole at a center portion, and fuel is injected into a combustion cylinder through the center hole of the swirler. A spray combustor having a fuel injection valve for spraying, wherein:
On the peripheral side, a flat plate area reaching the center hole is continuously provided,
Provided a plurality of air holes smaller than the center hole diameter in the plate area
It is characterized by:

[0006]

According to the feature of the present invention , a flat plate area extending to the center hole is continuously provided on the inner peripheral side of the blade cutting and raising area constituting the swirling blade, and air holes smaller than the center hole diameter are formed in the flat plate area. Since a plurality of fuel sprays are provided, the fuel spray injected into the combustion cylinder is sprayed immediately after the injection by the air sent from the center hole and the air sent from the surrounding air holes near the outlet of the center hole. Is transported downstream without being disturbed. In other words, by the air from the center hole and the air from the surrounding air holes, the spray is injected without being disturbed by the swirling flow early,
Flame is held under the influence of swirling flow. Therefore, the flame is formed at a certain distance from the exit of the center hole, and no soot adheres to the center hole and the swirl vanes. In addition, when there is no air hole around the center hole, hindrance of spraying near the center hole outlet is not observed, but a stagnation region is formed there, and as the swirl vane inner diameter increases, soot adhesion is observed. to become.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view showing one embodiment of the spray combustor of the present invention, FIG. 2 is a detailed view of a main part thereof, (A) is a front view, and (B) is a longitudinal sectional view. The nozzle mounting flange 1 has a cylindrical plate-shaped main body 1a, a cylindrical part 1b integrally protruded from the inner periphery of the main body 1a, and a circular tubular body protruded integrally from one surface of the main body 1a. And an annular flange 1c. On one surface of the nozzle mounting flange 1, a substantially cylindrical primary air cylinder 2, a substantially cylindrical secondary air cylinder 3 fitted to the primary air cylinder 2 at a predetermined interval, and a secondary air cylinder 3 And a substantially cylindrical outer cylinder 4 which is fitted at a predetermined interval to the outside, and a substantially cylindrical air inflow cylinder 5 is attached to the other surface of the nozzle mounting flange 1.

The primary air cylinder 2 has a tapered cone portion 2a integrally formed at one end, and the other end is fitted to the annular flange portion 1c of the nozzle mounting flange 1.
The secondary air cylinder 3 has an annular plate portion 3a and an annular tube portion 3b integrally at one end, and an annular plate portion 3d at the other end integrally with a tube plate. Nozzle mounting flange 1
Attached to. The outer cylinder 4 has a tubular plate-shaped annular plate portion 4a at one end and a tubular plate-shaped annular plate portion at the other end.
4b, which is in contact with the nozzle mounting flange 1 via the secondary air cylinder annular plate 3d. One end of the air inflow cylinder 5 has a main body portion of the nozzle mounting flange 1.
1a, and has a disk portion 5a integrally formed at the other end thereof for closing the other end of the air inflow cylinder 5. A substantially cylindrical combustion cylinder 7 is fitted inside the distal end of the outer cylinder 4 at a predetermined interval, and one end of the combustion cylinder 7 is fixed to the inner periphery of the annular plate 4 a of the outer cylinder 4.

The other end of the combustion tube 7 has a swirling cone 7a and a flame stabilizer (7b, 7b) having a tapered shape as an airflow guide.
c, 7d, 7e, 7f) are formed and fixed to the annular pipe portion 3b of the secondary air cylinder 3. Flame stabilizers (7b, 7c, 7d, 7e,
7f) is a swirl vane 7b which is a main part thereof,
A turning blade outer peripheral wall 7e as an air blocking wall provided on the entire outer periphery of 7b, a plate region 7c provided on the inner peripheral side of the turning blade 7b which is a blade cutting and rising region, and a plurality of plates provided in the plate region 7c And a center hole 7d at the center. The air hole 7f is smaller than the center hole 7d. The outer peripheral wall 7e of the swirling vane of the combustion cylinder 7 is fixed to the annular pipe portion 3b of the secondary air cylinder 3.

A substantially cylindrical nozzle adapter 9 is fitted in the cylindrical portion 1b of the nozzle mounting flange 1. At one end of the nozzle adapter 9 is a fuel injection valve that sprays fuel
11 and an igniter 10 for igniting the fuel. Fuel is pressure-fed to the fuel injection valve 11 from a fuel supply device (not shown) via a fuel supply pipe 20 penetrating the disk portion 5a of the air inflow cylinder 5 and a nozzle adapter 9. A combustion air supply pipe 6 connected to a combustion air supply device (not shown) is connected to the air inflow cylinder 5.

With the above construction, the combustion air chamber 12 surrounded by the air inlet cylinder 5 and the nozzle mounting flange 1 is provided.
And a first air chamber 13 surrounded by the primary air cylinder 2 and the nozzle mounting flange 1 and communicating with the inside of the combustion cylinder 7 through the center hole 7d of the flame stabilizer (7b, 7c, 7d, 7e, 7f). And a second air chamber formed between the primary air cylinder 2 and the secondary air cylinder 3
14, a third air chamber 15 surrounded by the outer cylinder 4, the nozzle mounting flange 1, the secondary air cylinder 3, and the combustion cylinder 7. A plurality of rectifying air holes 16 for communicating the combustion air chamber 12 and the first air chamber 13, a combustion air chamber 12 and a second air chamber 14 are formed in the main body 1 a of the nozzle mounting flange 1.
A plurality of rectifying air holes 17 communicating with the
And a plurality of rectifying air holes 18 for communicating the air flow with the third air chamber 15. The combustion cylinder 7 has a number of holes 19 in part.
Are formed.

Next, the operation will be described. The fuel supplied to the fuel injection valve 11 through the fuel supply pipe 20 and the nozzle adapter 9 is injected from the injection hole of the fuel injection valve 11, and the flame is supplied to the center hole of the flame stabilizer.
It flows into the combustion cylinder 7 through 7d. On the other hand, the combustion air pumped into the combustion air chamber 12 through the combustion air supply pipe 6 passes through the rectification air hole 16 formed in the main body 1a of the nozzle mounting flange 1 also serving as a rectification plate. 1 air chamber 13
And flows into the combustion cylinder 7 as primary air A1 along with the fuel sprayed from the fuel injection valve 11 through the flame holder center hole 7d. Therefore, even when the spray amount of the fuel into the combustion cylinder 7 is small, the primary air A1 can give a sufficient penetration force to the fuel.

The combustion air in the combustion air chamber 12 is supplied as secondary air to the second air chamber 14 through the rectifying air hole 17, and is supplied to the swirl vanes 7b and 7b of the flame stabilizer. 7b
It passes through the air hole 7f of the flat plate area 7c on the inner peripheral side. At this time,
The secondary air A2 that has passed through the swirl vanes 7b flows into the combustion cylinder 7 as a swirl flow A6 that flows in the forward and circumferential directions, and becomes a smooth flow by the swirler cone 7a that is an airflow guide of the combustion cylinder 7. And serve to inflame.

In the present invention, since the swirl vane outer peripheral wall 7e, which is an airflow blocking wall, is formed, the outflow of the airflow A5 that tends to exit radially outward of the swirl vane 7b is prevented, and the airflow A5 in the forward and circumferential directions is prevented. A smooth swirling flow A6 is formed in the airflow. The secondary air A2 that has passed through the air holes 7f provided in the flat plate region 7c on the inner peripheral side of the swirling blade 7b flows inward A7 from the spray boundary region. Due to the inward airflow A7, the spray is not disturbed by the swirling flow immediately at the early stage of the spray formation, that is, immediately after entering the combustion cylinder 7, so that the flame holding property and the combustibility due to the uneven fuel spray and the like are improved. Adverse effects, and fuel wetting and soot adhesion to the swirl vanes can be avoided. In addition, when there is no air hole 7f, a stagnation region is formed, which is one of the factors of soot adhesion, but in the present invention, due to the function of the air hole 7f,
Both the effect of preventing the formation of the stagnation region and the effect of raising the flame work, and the flame is formed from a certain distance downstream from the center hole 7d.
However, due to the effect of the swirling flow A6 passing through the swirling blade 7b, the flame holding property is improved as compared with the conventional case. Also, the amount of air passing through the swirl vanes 7b and the air holes in the plate area 7c on the inner peripheral side of the swirl vanes 7b
The ratio of the 7f to the passing air amount is almost determined by the opening area ratio, so the secondary air
Even when the flow rate of A2 is changed, the effect of preventing the soot from adhering to the flame stabilizing property, the combustibility, and the flame stabilizing device is not significantly changed. Further, the combustion air in the combustion air chamber 12 is supplied to the third air chamber 15 through the rectified air holes 18 and flows into the combustion cylinder 7 as the tertiary air A3 through the holes 19. Thus, when the fuel injected from the injection hole of the fuel injection valve 11 is ignited by the igniter 10, a stable flame is formed in the combustion cylinder 7.

In the embodiment described above, the turning blade outer peripheral wall 7e which is an airflow blocking wall is provided on the entire outer periphery of the turning blade 7b.
A flat plate area 7c having a plurality of air holes 7f is provided on the inner peripheral side of the swirling blade 7b, the supply air is separated into primary air and secondary air by the primary air cylinder 2, and a swirler / air flow guide is further provided. Although the configuration is such that the cones 7a are provided, it is not always necessary to provide all the components. For example, in the spray combustor shown in FIG. 3, the swirl vane outer peripheral wall 7e which is an airflow blocking wall is provided on the entire outer periphery of the swirl vane 7b, but the above configuration is not provided. However, also in the example shown in FIG. 3, it is possible to prevent a part of the air that passes through the swirl vanes 7b and enters the combustion cylinder 7 from flowing in the radial outside of the swirl blades 7b.

In addition, in the example of the spray combustor shown in FIG. 4, in addition to the structure in the structure of the spray combustor shown in FIG. As a result, the air passing through the center hole 7d and the air passing through the swirl vanes 7b can be completely separated and independent, and a stable flame can be formed even when the fuel flow rate is largely changed.

Also, in the example of the spray combustor shown in FIG.
Is not provided. However, also in the example shown in FIG. 5, the presence of the air holes 7f eliminates the disadvantage that the spray enters the combustion cylinder 7 due to the swirling flow and is immediately disturbed.

The spray combustor shown in FIG. 6 has a configuration in addition to the configuration shown in FIG. 5, that is, a configuration of a primary air cylinder 2 for separating supply air into primary air and secondary air. It has a configuration. Further, the spray combustor shown in FIG. 7 has the above configuration, that is, the swirl vane outer peripheral wall 7e which is an airflow blocking wall.
, That is, the air hole 7f, that is, the primary air cylinder 2 is provided, but the configuration, that is, the structure provided with the swirler cone 7a as the airflow guide is not provided. The spray combustor shown in FIG. 8 shows an example in which the cylindrical block 21 is provided as an airflow blocking wall in place of the swirl vane outer peripheral wall 7e having the following configuration. In addition, although the other configuration is provided, the configuration, that is, the configuration provided with the swirler cone 7a as the airflow guide is not provided.

The spray combustor shown in FIG. 9 has a conical block 22 installed as a swirler cone in the above configuration. Other configurations are also available. The spray combustor shown in FIG. 10 is provided with a cylindrical-conical block 23 instead of a swirler outer peripheral wall as an airflow blocking wall having a swirler cone as an airflow guide having the following configuration. , Is also provided. Further, the spray combustion device shown in FIG. 11 has a configuration in which the primary air cylinder 2 is removed from the embodiment shown in FIG. That is,
, And does not have the configuration.

In the above embodiment, the pressure injection valve is used as the fuel injection valve, but an air injection nozzle, an ultrasonic nozzle, or a fuel return nozzle may be used as the fuel injection valve. Further, as one of the fuel proportional control injection systems, a spray cut system may be used.

[0021]

According to the present invention the above configuration consists of action, according to the spray combustor according to claim 1, flat region extending to the center hole on the inner peripheral side region and raised blade cutting constituting the swivel blade Are continuously provided, and a plurality of air holes smaller than the center hole diameter are provided in the flat plate region, so that the fuel spray injected into the combustion chamber has air near the center hole outlet and air sent from the center hole and its surroundings. By the air sent from the air hole of the above, the spray is immediately transported downstream without being disturbed immediately after the injection. Therefore, the flame is formed at a certain distance from the exit of the center hole, and soot is prevented from adhering to the center hole and the swirling blade .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a spray combustor of the present invention.

FIG. 2 is a detailed view of a main part of the spray combustor shown in FIG.

FIG. 3 is a longitudinal sectional view of a spray combustor showing another embodiment.

FIG. 4 is a longitudinal sectional view of a spray combustor showing another embodiment.

FIG. 5 is a longitudinal sectional view of a spray combustor showing another embodiment.

FIG. 6 is a longitudinal sectional view of a spray combustor showing another embodiment.

FIG. 7 is a longitudinal sectional view of a spray combustor showing another embodiment.

FIG. 8 is a longitudinal sectional view of a spray combustor showing another embodiment.

FIG. 9 is a longitudinal sectional view of a spray combustor showing another embodiment.

FIG. 10 is a longitudinal sectional view of a spray combustor showing another embodiment.

FIG. 11 is a longitudinal sectional view of a spray combustor showing another embodiment.

FIG. 12 is a longitudinal sectional view showing an example of a conventional spray combustor.

FIG. 13 is a longitudinal sectional view showing an example of another conventional spray combustor.

FIG. 14 is a detailed view of a main part of still another conventional spray combustor.

[Explanation of symbols]

 7 Combustion cylinder 7a Swirler cone as airflow guide 7b Swirl vane 7c Plate area 7d Center hole 7f Air hole 11 Fuel injection valve

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-17410 (JP, A) JP-A-5-172311 (JP, A) JP-A-4-350403 (JP, A) 87017 (JP, U) Heikai 2-28924 (JP, U) Heisei 4-33822 (JP, U) Heisei 5-79209 (JP, U) (58) Fields surveyed (Int. ⁷ , DB name) F23D 11/24

Claims (1)

(57) [Claims] A swirl vane having a central hole to 1. A central, through the central hole of the orbiting blades, a spray burner and a fuel injection valve for spraying fuel into the combustion cylinder, the handed
On the inner peripheral side of the blade cutting and raising area constituting the rotating blade,
A flat plate region extending to the core hole is provided continuously, and the flat plate region
A spray combustor comprising a plurality of air holes smaller than a center hole diameter .