JPH0252911A - high load burner - Google Patents

Abstract

PURPOSE:To form a hollow flame for promoting combustion by drilling a main flame nozzle a certain distance away from a pilot flame nozzles of a flame stabilizing pilot burner in the center. CONSTITUTION:A cylindrical mixing chamber 4 is provided with a plate 5 on its upper opening, and reduced in diameter at its lower portion to connect to an outlet 7 of an air blower 6. A gas supply nozzle 8 is furnished on the outlet 7. A pilot burner B is located in the center of the plate 5 so as to locate pilot flame nozzles 2 a little above a combustion face 1 on the plate 5, and a number of slit-like main flame nozzles 3 are provided at position a certain distance away from the pilot flame nozzles 2 on the plate 5 and arranged radially at equal distances. As the slit-like main flame nozzles 3 are burned under a large input, combustion flame (a) extends upward with vigor and the central part of the flame becomes hollow.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a high-load burner that is compact and can provide high calories by increasing the amount of combustion per unit area.

[Conventional technology]

For example, a high-load burner uses the entire amount of combustion air as primary air, mixes it with fuel gas, and burns it under a large input, thereby increasing the amount of combustion per unit area and producing high calories in a compact size. However, it is an important problem to eliminate the combustion flame lift phenomenon caused by excessive input or the like or the combustion flame blow-off phenomenon caused by insufficient mixing of the air-fuel mixture.

However, in the conventional technology, no measures against lift or blow-off are taken.

[Problem to be solved by the invention]

This invention has been made in view of the above points, and it is possible to achieve high loads without lift or blow-off by mixing air into the air-fuel mixture induced by the flame flow and by holding the spark with a permanent pilot burner for flame stabilization. Moreover, the aim is to provide a high-load burner that can provide stable combustion.

[Means to solve the problem]

In order to achieve the above object, in the high-load burner of the present invention, a lean air-fuel mixture with a low air-fuel ratio, which has been mixed in advance with an arbitrary mixing means, is introduced into a cylindrical outer shell forming a combustion chamber and combusted. A flame-holding pilot burner is provided in the center of the combustion surface of a cylindrical burner body so as to slightly protrude from the combustion surface, and a large number of main flame holes provided on the combustion surface of the burner body are located from the flame-holding pilot burner. They are drilled at positions separated by a certain distance.

[For production]

In the high-load burner according to the present invention configured as described above, the main flame hole of the burner body is bored at a certain distance from the pilot flame hole of the central flame-holding pilot burner. The combustion flame is formed in a hollow shape, and the central cavity of the combustion flame has a negative pressure, so the suction force attracts air into the cavity, mixes it with the lean mixture from the main flame hole, and promotes its combustion. At the same time, it is also used as combustion air for the flame-holding pilot burner located in the center of the cavity to ensure stable combustion of the pilot flame, and the fuel necessary to stabilize the combustion flame in the burner body is always available for high-load combustion. It is to be maintained.

〔Example〕

Embodiments of the high-load burner of the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, A is a burner body, which is equipped with a plate plate 5 at the upper opening of a cylindrical mixing chamber 4, has a narrowed lower part, and is connected to a discharge lower of a supply air blower 6. has a configuration in which a gas supply nozzle 8 is exposed, and a pilot burner B for flame stabilization is provided in the center of the plate plate 5 with its pilot flame hole 2 slightly protruding from the combustion surface 1 of the plate plate 5. At the same time, a large number of slit-shaped main flame holes 3 are radially bored at equal intervals at a position a certain distance away from the pilot flame hole 2 in the plate plate 5. Reference numeral 9 denotes a cylindrical outer shell, which has a ventilation gap 10 between it and the burner body A on the outside of the burner body A, and forms a combustion chamber 12 between the upper end opening 11 and the plate plate 5 of the burner body A. It is provided. Note that if the outer peripheral edge of the plate plate 5 is slightly protruded outward from the cylindrical mixing chamber 4 to form a flange 13, and the flange 13 is slightly exposed into the ventilation gap 10, the two parts of the ventilation gap 1o are A vortex is generated in the flowing air, promoting mixing into the air-fuel mixture and increasing combustion efficiency. Moreover, if the slit-shaped main flame hole 3 is shaped so that it is narrow on the inside and widens toward the outside, it is possible to equalize the area of the flame hole.

In the above configuration, forced air from the air supply blower 6 and fuel gas from the gas supply nozzle 8 are mixed at a certain ratio between the discharge lower of the air supply blower 6 and the mixing chamber 4 to create a preset air space. A lean air-fuel mixture with a small fuel ratio (ratio of fuel to air) is formed, and a large amount of the lean air-fuel mixture is ejected from the slit-shaped main flame hole 3 of the plate plate 5 and combusted, thereby forming a high-load combustion flame a. However, the slit-shaped main flame hole 3 is bored at a certain distance from the pilot flame hole 2 of the central flame-holding pilot burner B, and the combustion is performed under a large input. , the combustion flame a extends upward vigorously, and its center is hollow, and the cavity has a negative pressure, so its suction force attracts air C from above into the cavity, and the combustion flame a side (outward)
The air is pulled into the air and mixed with the lean mixture from the slit-shaped main flame hole 3, and in combination with the swirling action of the secondary air flow caused by the collar 13 formed on the outer peripheral edge of the plate plate 5, the combustion is promoted. It also provides combustion air for the flame-holding pilot burner B located in the center of the cavity, stably burning the standing pilot flame, stably holding the combustion flame A, and maintaining efficient high-load combustion. .

In addition, in the above embodiment, the burner body A is cylindrical, but
It can also be square or other shape, and although a part of the combustion air is used as primary air to mix with the fuel gas as a means of mixing a lean mixture, it may be mixed by other means. .

〔Effect of the invention〕

Since the present invention has the above configuration, it produces the following effects.

A flame-holding pilot burner is provided in the center of the combustion surface of the burner body, and a number of main flame holes are bored in the combustion surface of the burner body at a certain distance from the flame-holding pilot burner. A cavity is formed in the combustion flame, and air is attracted by the negative pressure in the cavity, and self-sufficient air is mixed into the mixture to promote combustion. Since the pilot flame is also used as combustion air, it burns stably and is always available as a spark for the combustion flame, so even though it is a lean mixture, there is no lift or blow-off, etc. under high load, and stable combustion is achieved. It is compact and exhibits high combustion efficiency.

In addition, since it is possible to stably burn a lean mixture with a low air-fuel ratio that has been premixed using any mixing means and under high load, the exhaust gas is not only low in NOx, but also produces no soot. .

Furthermore, a flame-holding pilot burner is provided in the center of the combustion surface of the burner body, and a number of main flame holes are bored at a certain distance from the flame-holding pilot burner in the combustion surface of the burner body. Since it has a simple structure, the cost is extremely low.

[Brief explanation of the drawing]

The drawings show an embodiment of a high-load burner according to the present invention, with FIG. 1 being a longitudinal sectional front view and FIG. 2 being a lateral plan view. A... Burner body, 1... Combustion surface, B... Pilot burner for flame holding, 2... Pilot flame hole, 3... Main flame hole, 9... Outer shell, 12... combustion chamber. Patent Applicant: Toho Gas Co., Ltd. Paloma Industries Co., Ltd. Figure 1 3: (Maku1shi 9:?) Throw 12: x or Fire Figure 2

Claims (1)

[Claims] A combustion surface of a cylindrical burner body (A) that introduces and burns a lean air-fuel mixture with a low air-fuel ratio that has been premixed by any mixing means into a cylindrical outer shell (9) that forms a combustion chamber (12). A flame-holding pilot burner (
B) are provided slightly protruding from the combustion surface (1), and a large number of main flame holes (3) provided on the combustion surface (1) of the burner body (A).
A high-load burner that is installed at a certain distance from the flame-holding pilot burner (B).