JPS5817370B2 - Fire ``en'' jet burner - Google Patents

Description

[Detailed description of the invention] FIELD OF THE INVENTION The present invention relates to a flame jet burner.

A flame jet burner injects air and fuel from its base into a combustion cylinder that has a nozzle at its tip for combustion, and ejects high-temperature combustion gas from the nozzle at high speed.

A conventional flame jet burner has a single annular air injection port at the periphery of the base of the combustion cylinder, a fuel injection port in the center, and a swirling flow of the injected air within the air guide path to the air injection port. A guide means is provided so that

The reason why this conventional flame jet burner has an annular air injection port on the periphery of the base is to prevent the injected fuel from coming into contact with the inner wall of the combustion cylinder and causing incomplete combustion, and to prevent the injected fuel from contacting the inner wall of the combustion cylinder and causing incomplete combustion. This is because the suction force draws the fuel in the center and mixes it with air.

However, the injected air forms a relatively regular flow along the inner wall of the combustion cylinder, and has the disadvantage that it is difficult to mix with the fuel near the center where the concentration is highest just by the suction force due to the swirling flow.

In other words, the air injected as a swirling flow has a strong tendency to spread outward due to the centrifugal force, so much of it flows along the inner wall of the combustion cylinder, resulting in a lack of air near the center. Mixing may be delayed.

Therefore, since the combustion speed is slow and the flame is long, the combustion tube becomes long and installation is likely to be subject to restrictions such as location.

Furthermore, in addition to being used for combustion, a considerable amount of the injected air is also discharged from the nozzle, making it difficult to achieve complete combustion unless the excess air ratio is increased.

The purpose of the present invention is to quickly and uniformly mix fuel and air in a flame jet burner, thereby increasing combustion efficiency. We focused on the fact that the regularization of the flow and the delay in the mixing of air and fuel were caused by just installing two or more air injection ports.

This was done based on the discovery that since air and fuel are quickly mixed and combusted, there is no risk of incomplete combustion due to the fuel coming into contact with the inner wall of the combustion cylinder even without providing an annular air injection port on the periphery of the base. .

In other words, two or more air injection ports that inject air as a swirling flow are provided at the base of the combustion cylinder, and the swirling flow of air ejected from each air injection port involves the flow of fuel, and also creates turbulence due to air collisions. The aim is to utilize this effect to quickly and uniformly mix fuel and air.

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

FIG. 1 is a longitudinal sectional view showing one embodiment of a flame jet burner according to the present invention, and FIG. 2 is an enlarged view of its base.

1 in the figure is a triple case 1a. It is a combustion cylinder consisting of 1b and 1c, and a nozzle 2 is provided at the tip.

An appropriate gap is provided between the cases Ia and 1b1c of the combustion tube 1, through which cooling water flows.

The cooling water enters from the water inlet 3 and flows to the drain port 4, and is used to protect the combustion tube 1 from high temperatures caused by combustion.

An annular air injection port 5a is opened at the base peripheral edge of the combustion tube 1, and a circular air injection hole 5b is provided in the center.

Spiral blades 7a and 7b are provided in air guide paths 6a and 6b for guiding air to both air injection ports 5a and 5b, respectively, as guide means for making the injected air into a swirling flow.

As the guide means, spiral grooves may be formed in place of the blades 7a and 7b, and any guide means may be used as long as the injected air forms a swirling flow.

Furthermore, injectors 9 whose tips serve as fuel injection ports 8 protrude at equal intervals between the air injection ports 5a and 5b.

High-pressure air is supplied to the air injection ports 5a, 5b from an air supply port 10 through air guide paths 6a, 6b, and to the fuel injection port 8 from a fuel supply port 11 through a fuel guide path 12. High-pressure fuel is supplied.

With this configuration, the fuel injected from the fuel injection port 8 is first caught in the swirling flow of air injected from the air injection port 5b in the center, and then gradually diffuses outward to the peripheral portion. A turbulent flow is generated by colliding with the swirling flow of air injected from the air injection port 5a, which spreads uniformly within the combustion cylinder 1, and the fuel and air are completely mixed.

At this time, it is more effective if the blades 7a and 7b are arranged so that the swirling directions of the air injected from both air injection ports 5a and 5b are opposite to each other.

This kind of flame jet burner not only uses the suction force of the swirling air flow outwards from the center to draw the fuel into the air flow (like the conventional flame jet burner), but also draws the fuel into the air flow ( The air is not drawn into a swirling flow and collided with each other to create turbulence, and the air is uniformly dispersed within the combustion tube 1 and mixed with the fuel, so the mixing is quick and wasteful. There is also less air discharged from the nozzle 2.

Therefore, since the combustion speed is high and the flame is short, the combustion tube 1 can be relatively short, and the overall size of the burner can be reduced.

Furthermore, since complete combustion can be achieved with a small amount of supplied air, higher temperature combustion gas can be ejected from the nozzle 2.

Furthermore, when igniting a flame jet burner, oxygen is mixed into the air to assist in ignition, and since the mixture with air is extremely good, there is also the advantage that sufficient ignition can be achieved even with a small amount of mixed oxygen.

In the flame jet burner shown in FIGS. 1 and 2, an inner air injection port 5b is provided at the center of the base of the combustion tube 1, and a plurality of fuel injection ports 8 are provided around it. There is no problem even if the fuel injection port 8 is singular or the air injection port 5b is provided offset from the center depending on the positional relationship with the fuel injection port 8.

FIG. 3 shows another example of the arrangement of the air injection ports and the fuel injection ports.

a is a double annular air injection port 13 at the periphery of the base of the combustion cylinder.
a, 13b are provided, and a fuel injection port 14 is provided in the center.

With this arrangement, the fuel injected from the fuel injection port 14 is not only sucked into the swirling flow of air injected from the inner air injection port 13b, but also is absorbed by both air injection ports 13a.
, 13b, the turbulent flow caused by the collision of the air causes the entire mixture to be mixed with air.

Further, there may be a plurality of fuel injection ports 14, and even both air injection ports 13a.

It is more effective if the swirling flow of the air injected from 13b is in the opposite direction.

b) Well, a plurality of air injection ports 15 are arranged at equal intervals, and a fuel injection port 16 is positioned between the air injection ports.

With this arrangement, the fuel injected from the fuel injection port 16 is not only caught up in the swirling flow of the air injected from the adjacent air injection port 15, but also the fuel injected from the air injection port 15 is The turbulence created by the collision mixes the whole with air.

In this case, it is more effective if the swirling directions of the air ejected from the adjacent air injection ports 15 are made to be opposite to each other.

As explained above, the flame jet burner according to the present invention mixes air and fuel through two effects: entrainment in the air injected as a swirl flow and turbulence caused by collisions between the injected air. Therefore, mixing is quick and uniform, and combustion efficiency is high.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view showing one embodiment of the flame jet burner according to the present invention, Fig. 2 is an enlarged view of its base, and Fig. 3 a.
-b are diagrams showing other examples of arrangement of air injection ports and fuel injection ports. Combustion cylinder, 1a, 1b, 1c: case, 2: nozzle, 3
: Water injection port, 42 drain port, 5a, 5b: Air injection port, 6a, 6b: Air guideway, 7a, 7b: Wings, 8: Fuel injection port, 9: Injector, 10: Air supply port, 11
: Fuel supply port, 12: Fuel guideway, 13a, 13b: Air injection port, 14: Fuel injection port, 15: Air injection port, 16
:Fuel injection port○

Claims (1)

[Scope of Claims] 1. In a flame jet burner that injects air and fuel into the combustion cylinder from an air injection port and a fuel injection port provided at the base of the combustion cylinder having a nozzle at the tip for combustion. A flame jet burner characterized in that it is provided with the air injection ports as described above, and is provided with a guide means for making the injected air into a swirling flow in the air guide path to each air injection port. 2. A flame jet burner as claimed in claim 1, characterized in that guide means in each air guide path is arranged to contain swirling flows in opposite directions. 3. A patent claim characterized in that an annular air injection port is provided at the periphery of the base of the combustion cylinder, an air injection port is also provided at the center, and one or more fuel injection ports are located between both air injection ports. The flame jet burner according to item 1. 4. The flame jet burner according to claim 1, characterized in that a double ring-shaped air injection port is provided on the peripheral edge of the base of the combustion cylinder, and one or more fuel injection ports are located in the center. . 5. The flame jet burner according to claim 3 or 4, characterized in that guide means are provided in both air guide paths so that the injected air forms a swirling flow in opposite directions. .