JPH0456208B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is particularly applicable to the low frequency range (100
This invention relates to a combustion noise reduction device that reduces noise (~500Hz).

(Prior Art) Conventionally, a combustion apparatus of the type in which a plurality of line-shaped burners a are arranged side by side in a combustion cylinder to which combustion air is forcibly supplied is provided with a secondary air ventilation gap b between them. known. However, as shown in Fig. 4, the secondary air flowing through the ventilation gap b flows along the sides of each linear burner a, and as a result is pushed by the secondary air flowing through the center of the ventilation gap b. Near the burner's burner, the secondary air tends to flow toward the burner, and this flow is not constant and constantly changes, causing the flame to oscillate, causing noise in the low frequency range. Occur.

Conventionally, this kind of noise has been reduced by attaching sound-absorbing materials to the exhaust pipe or intake port.

(Problems to be Solved by the Invention) However, with this sound absorbing material, it is difficult to absorb particularly low frequency noise.

An object of the present invention is to provide a device that reduces low frequency noise generated during combustion.

(Means for Solving the Problems) In order to achieve the above object, the present invention has the following features:
The described combustion noise reduction device has a plurality of line-shaped burners arranged side by side in a combustion cylinder to which combustion air is forcibly supplied, with a secondary air ventilation gap between them. , a secondary air tuner having a circular cross section is provided along the longitudinal direction of the linear burners, the upper end of which is located above the center between the linear burners and facing below the flame opening surface of the linear burners; The combustion noise reduction device according to claim 2 is one in which a plurality of line-shaped burners are arranged side by side in a combustion cylinder to which combustion air is forcibly supplied, with a secondary air ventilation gap between them. A flat plate-shaped secondary air tuner is provided along the longitudinal direction of the linear burners, the upper end of which is located above the center between the linear burners and located below the flame opening surface of the linear burners. Become.

(Function) In the case of a device having the above configuration, between the ventilation
This makes it possible to suppress the flow of secondary air flowing through the center of the flame, thereby preventing the secondary air from moving toward the flame opening as much as possible, allowing the flame to flow in any direction without being restricted. It is possible to prevent as much as possible the occurrence of combustion noise caused by the secondary airflow that flows freely.

(Example) An example of implementing the present invention will be explained with reference to the attached drawings.

In the drawings, 1 indicates the combustor main body, 2 indicates a combustion shell provided therein, and 3 indicates a plurality of linear burners provided within the combustion shell 2, and the linear burners 3 have secondary air flowing between them. They are arranged side by side with a ventilation gap.
Fuel gas is supplied to each line-shaped burner 3 via a manifold pipe 4 provided with a gas nozzle 4a corresponding to each burner 3. Reference numeral 5 indicates a blower connected to the lower part of the combustion shell 2 for forcibly supplying combustion air, 6 indicates a water heat exchanger provided at the upper part of the combustion shell 2, and 7 indicates an exhaust passage connected to the upper part.

In the embodiment shown in FIGS. 1 and 2, a secondary air tuner 8 having a circular cross section and whose upper end faces a position located above the center between the linear burners 2 and below the flame opening surface 2a of the linear burners 2. is provided along the longitudinal direction of the linear burner 2, and the tuner 8 is approximately 3 mm in diameter at a position approximately 5 mm below the flame opening surface 2a.
A round bar was provided along the length direction of each linear burner 3.

When doing so, the round rod can be used to suppress the flow of secondary air flowing through the center of the ventilation gap, so that the secondary air is directed toward the flame outlet as shown by solid line A in Figure 4. It was possible to suppress this as much as possible, and also to suppress the generation of secondary air flow with no fixed direction as shown by the chain line B, thereby suppressing the fluctuation of the flame, thereby reducing the combustion noise. According to experiments, when the tuner 8 is not present, the 53rd to 54th horns are
I was able to make it less than 50 horns.

What is shown in FIG. 3 is the central upper part between the linear burners 2, and the flame opening surface 2a of the linear burners 2.
A flat plate-shaped secondary air tuner 8 whose upper end faces a lower position is provided along the longitudinal direction of the linear burner 2, and the secondary air tuner 8 is provided between the ventilation holes at the lower end of the line burner. A metal plate was provided over a range from the position to a position approximately 6 mm below the flame outlet surface 2a.
In this case, the flow of secondary air flowing through the center of the ventilation gap can be suppressed by the metal plate,
This also prevented secondary air from flowing toward the flame opening and causing the flame to sway.

(Effect of the invention) As described above, the combustion noise reduction device according to claim 1 has the following effects:
By providing a secondary air tuner with a circular cross section along the longitudinal direction of the linear burners, the upper end of which is located above the center between the linear burners and facing below the flame opening surface of the linear burners. The combustion noise reduction device according to the second aspect of the present invention includes a flat secondary air tuner whose upper end faces a position below the flame opening surface of the linear burner, which is located above the center between the linear burners. By providing it along the direction, it is possible to prevent the secondary air from flowing toward the flame outlet side and causing the flame to waver as much as possible.
This makes it possible to reduce the noise generated during combustion as much as possible.

[Brief explanation of the drawing]

FIG. 1 is a cutaway side view showing one example of implementing the present invention;
FIG. 2 is an enlarged view of the main parts thereof, FIG. 3 is an enlarged side view of the main parts showing another embodiment, and FIG. 4 is an enlarged side view showing the main parts of the conventional example. 1... Combustor main body, 3... Line burner, 8
...Secondary air synchronizer.

Claims (1)

[Scope of Claims] 1. In a combustion cylinder to which combustion air is forcibly supplied, a plurality of line-shaped burners are arranged side by side with a secondary air ventilation gap between them, A combustion sound formed by providing a secondary air tuner with a circular cross-section along the longitudinal direction of the linear burners, the upper end of which faces a position below the flame opening surface of the linear burners and located above the center between the linear burners. Lowering device. 2. When a plurality of line-shaped burners are arranged side by side with a secondary air ventilation gap between them in a combustion cylinder to which combustion air is forcibly supplied, the line-shaped burners are A combustion noise reduction device comprising a flat secondary air tuner provided along the longitudinal direction of the linear burner, the upper end of which is located at the upper center of the linear burner and faces below the flame opening surface of the linear burner.