JPS6020008A - pulse combustor - Google Patents

Abstract

PURPOSE:To reduce the generation of a combustion noise and to enable continuance of stable pulse combustion, by a method wherein a number of nozzles through which fuel is injected into a combustion chamber are bored in the side, and an air plate having a number of air ports is located on the upper stream side of the combustion chamber. CONSTITUTION:Fuel injection nozzles 14 are bored in the side of a fuel feed cylinder 15, and this causes fuel gas to flow toward the circumference of a combustion chamber 1. The air for combustion is fed through a number of air ports 9, and is mixed with fuel gas, fed to the combustion chamber 1, in the vicinity of the air ports 9. This causes a flame 13 to be formed in a dispersing manner in the vicinity of such mixture part of the fuel gas with the air for combustion, and the generation of a combustion noise is reduced. Further, an air chamber 10 is formed on the upper stream side of an air plate 8 to uniformize the air for combustion, and the uniformly dispersed flame is formed in the combustion chamber to further reduce the generation of the combustion noise.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement of a pulse combustor used as a heating device for industrial, commercial or domestic water heaters, hot air equipment, etc.

[Conventional configuration and problems]

A conventional pulse combustor has a combustion chamber, a tail pipe,
It consisted of an air passage with an air valve and a fuel passage with a fuel valve. This type of pulse combustor generally operates as follows.

That is, upon starting (ignition), combustion air is first supplied to the combustion chamber by a blower, and then fuel is supplied. If ignited with an igniter or the like at this stage, explosive combustion will occur, but at this time, the air valve and fuel valve will be opened due to the pressure increase in the combustion chamber, cutting off the supply of fuel and air.

After the combustion gas is discharged from the sol pipe, the pressure in the combustion chamber becomes negative pressure, the fuel valve and the air valve are closed, and air and fuel are supplied to the combustion chamber. This supply and the same song,
The hot combustion gases flow back and ignite the fuel/air mixture, causing another explosive combustion. After this, the same ignition, ignition, and suction of fuel and air occur without air blowing from the blower, and regular explosive combustion continues.

Some pulse combustors of this type supply fuel and air separately to a combustion chamber, mix them in the combustion chamber, and then perform pulse combustion. had the disadvantage of making a loud combustion noise.

In addition, fuel and air are mixed in advance, and this air-fuel mixture is supplied to the combustion chamber through a flame trap with many holes.
There is also a type of pulse combustor that performs pulse combustion. This type of pulse combustor has the disadvantage that a combustion condition, that is, flashback, occurs upstream of the flame trap, which often causes interruption of pulse combustion, and as a result, it is difficult to continue stable combustion as a pulse combustor. accompanied by.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a pulse combustor which eliminates the drawbacks of conventional devices as described above and which produces quiet combustion and is capable of continuing stable pulse combustion.

[Structure of the invention]

The pulse combustor according to the present invention is a pulse combustor that includes a combustion chamber, a tail pipe, and a fuel supply tube protruding into the combustion chamber, and the fuel injection port to the combustion chamber is connected to the fuel supply tube. An air plate having a large number of holes in the side surface and a large number of air holes is provided on the upstream side of the combustion chamber, the fuel supply cylinder is located in the center of the air plate, and an air chamber is provided upstream of the air plate. It is characterized by the fact that it was established.

[Explanation of Examples]

The invention will now be described in more detail with reference to the drawings, which illustrate preferred embodiments of the invention.

FIG. 1 shows a cross-sectional view of a pulse combustor according to the invention.

In FIG. 1, 1 is a combustion chamber, 2 is a tail pipe, 3 is an air passage, and 4 is a fuel passage. Although not shown, a cushion chamber, a muffler, or the like is often installed downstream of the tail pipe 2. 5 is a fuel valve provided in the fuel path, and 6 is an air valve provided in the air path. A valve chamber 7 is provided downstream of the air valve 6. 8 is an air plate that partitions the air chamber 10 connected to the air path 3 and the combustion chamber 1, and the air plate 8 is provided with a large number of air ports 9,
The air chamber 10 and the combustion chamber 1 are communicated with each other.

A plan view of the air plate 8 is shown in FIG. Reference numeral 11 denotes an ignition electrode, the discharge ignition portion of which is exposed to the combustion chamber 1. 1
2 is an ignition transformer for the ignition electrode 11; 1
3 schematically shows a flame.

Reference numeral 14 designates a large number of fuel injection ports formed in the fuel supply tube 15.

Next, the operation of the illustrated embodiment will be explained. fuel gas 16
is supplied to the combustion chamber 1 from the fuel injection port 14 through the fuel path 4. Combustion air 17 is fed at IN 1m (not shown)
The power of the air valve G1 is supplied to the combustion chamber 1 from the air port 9 through the valve chamber 7, the air passage 3 and the air chamber 10. The air and fuel supplied into the combustion chamber 1 are mixed, ignited by the spark discharge of the ignition electrode 11, and exploded, producing a flame 1.
3 is formed.

Due to the exposure, the pressure inside the combustion chamber increases, the air valve 6 and the fuel valve 5 are closed, and the supply of fuel gas and combustion air is cut off. The combustion gases pass through a narrow tailpipe 2 and are exhausted out of the combustor.

When the combustion gas is discharged from the tail pipe 2, a negative pressure is generated inside the combustion chamber 1, and the fuel valve 5 and air valve 6 open.
Fuel gas and combustion air are sucked into the combustion chamber 1 and burned!
+1 gas and combustion air mix.

At that time, the high temperature combustion exhaust gas flows back into the combustion chamber 1, the mixture of combustion exhaust gas and combustion air is ignited, and an explosion occurs again. Then, similar explosions occur one after another, resulting in a pulse combustion state. When the pulse combustion state is reached, send J! 1
Even if m stops, fuel gas and combustion air are automatically drawn into the combustion chamber.

A fuel injection port 14 is bored in the side of the fuel supply cylinder 15,
The fuel gas flows toward the periphery of the combustion chamber 1.

Further, combustion air is supplied from a large number of air ports 9, and mixes with the fuel gas supplied to the combustion chamber 1 near the air ports 9.

The flames 13 are formed in a dispersed manner near the mixing portion of the fuel gas and combustion air.

As a result, combustion noise was reduced.

An air chamber 10 is provided upstream of the air plate 8.

This is to ensure that the combustion air supplied through the air valve 6 is uniformly supplied into the combustion chamber 1 from each air port 9. The combustion air homogenized by the action of the air chamber 10 is uniformly dispersed within the combustion chamber 1, and as a result, a uniformly distributed flame is formed within the combustion chamber.

Therefore, it contributes to reducing combustion noise.

FIG. 3 shows the results of comparing the conventional example and the present invention with respect to combustion noise. As a conventional example, a type was used in which fuel gas and combustion air were separately supplied to the combustion chamber to avoid combustion. The horizontal axis is the combustion amount (kcat,,'h),
The vertical axis shows the noise (e, Δ range). The noise measurement was performed at a position 1 m away from the combustion chamber 1. The pulse combustor according to the present invention shows a value lower by about 5d [3] than that of the conventional example.

[Effects of the Invention] As explained above, as a result of successfully forming a flame dispersed by a large number of fuels, fuel gas supplied from a large number of air ports, and combustion air, combustion noise has been reduced compared to the conventional method (compared to the previous two). Therefore, the pulse combustor according to the present invention can be used as a low-noise combustor.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, and FIG. 2 is a front view of the air plate of the present invention. FIG. 3 shows the results of comparing the conventional example and the present invention regarding combustion noise. 1... Combustion chamber 2... Tail pipe 5... Fuel valve G... Air valve 8... Air plate 9...
・Air port 14...Fuel spout 15...Fuel supply cylinder Patent applicant Matsushita Electric Industrial Co., Ltd.

Claims (1)

[Claims] This is a pulse combustion feeder that connects a combustion chamber, a tail pipe, and a fuel supply tube that protrudes into the combustion chamber. -1-flow (11th stage t) of the combustion chamber, the combustion chamber 1 is located in the center of the air plate, and an air chamber is provided upstream of the air plate. The pulse combustor is characterized by the fact that it has been installed.