JPS60211210A - Pulse burner - Google Patents

Abstract

PURPOSE:To prevent beat noise in a pulse burner during combustion, by partitioning the outlet sof tail pipes and the inlets of exhaust gas by a semi-cylindrical bulkhead having a bottom, as well as to partition an exhaust gas cushion chamber by a bulkhead, and by providing a connecting hole in the center of a bulkhead. CONSTITUTION:Since both of exhaust gas cushion chambers 7 and 8 are connected by a connecting hole 21, higher pressure of combustion gases 27 and 28 in the exhuast gas cushion chambers 7 and 8 acts on the gas in the other chamber, forcibly oscillates it and synchronizes it. The connecting hole 21 is located near the bottoms 31 and 32 of a semi-cylindrical bulkhead, and it effectively works to transfer static pressure, combining large jetting speed of combustion gases 27 and 28 injected from tail pipes 5 and 6. With such an arrangement, more synchronized combustion is obtainable. In addition, pulsation by combustion gas does not oscillate the bottom plates, because the combustion gas does not directly hit the bottom plates. As a result, beat noise in a pulse burner during combustion can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an improvement in a pulse combustion device used as a heating device for industrial, commercial or domestic water heaters, hot air blowers, and the like.

Conventional configuration and problems Conventionally, pulse combustors have a high flow rate of combustion gas and are pulsating, so they can be used as combustors with high heat exchange efficiency, and furthermore, they do not require a power source outside the plate during operation. This made it promising as a combustor with low running costs. Such a pulse combustor produces loud combustion noise and has a narrow variable range of heat output. Therefore, an attempt was made to reduce combustion noise and widen the variable range of heat output by burning two pulse combustors with low heat output in parallel.

At this time, if the exhaust cushion chamber is shared and the tail pipes of both pulse combustors are connected to the exhaust cushion chamber, the ignition performance will be poor. In particular, when one pulse combustor is operating, it is difficult to ignite the other. In addition, even when both were in combustion, combustion failures frequently occurred and combustion stoppage occurred.

On the other hand, if each pulse combustor is provided with an exhaust cushion chamber, each pulse combustor will have a large combustion volume.

Because differences in the frequency of pulse combustion occurred due to differences in the amount of suction air, structural dimensions, etc., the combustion sound was accompanied by a burbling phenomenon. As a result, the combustion noise was not reduced as much as expected and a harsh sound remained.

Purpose of the Invention The purpose of the present invention is to provide a quiet and highly efficient pulse combustion device that corrects the drawbacks of the prior art and uses a simple method to share an exhaust cushion chamber, prevents the generation of combustion noise, and increases thermal efficiency. shall be.

Structure of the Invention The present invention partitions an exhaust cushion chamber with a partition plate,
A pulse combustion device characterized in that an exhaust cushion chamber of each combustor is formed, a tail pipe outlet and an exhaust inlet are partitioned by a semi-cylindrical plate having a bottom, and a communication port is provided in the central partition plate. be.

An explanatory diagram of an embodiment is a configuration diagram of a pulse combustion apparatus according to an embodiment of the present invention. In the figure, 1.2 is a pulse combustor. 3 and 4 are combustion chambers, and 5 and 6 are till pipes communicating with an exhaust cushion chamber 7.8.

9.10 is a gas distributor looking into the combustion chambers 3 and 4, 11.12 is an air passage leading to the combustion chambers 3 and 4,
13.14 is the spark plug, 15.16 is the air valve, 1
7. , 18 is a gas valve, 19 is an air cushion chamber, 2o is a partition plate forming two exhaust cushion chambers 7.8, 21 is a communication hole provided in the partition plate 20, 22
．． 23 is an exhaust pipe, 24 is combustion air, 26.26 is combustion gas, 27.28 is combustion gas, and 29 is water. Further, 27 is a bottom plate provided with exhaust pipes 22 and 23, and the can body 36 and the gasket 28 are sandwiched and fixed with bolts 30. 31.32 is the bottom of the semi-cylindrical partition plate, 33 is the bolt that fixes it to the partition plate 2o, 34.35 is the cylindrical part of the semi-cylindrical partition plate, and the above constitutes a pulse combustor. ing.

Next, the operation will be explained. Fuel gas 25, 26 passes through gas valves 17, 18 and is supplied to combustion chambers 3, 4 from distributors 9, 1o having a large number of nozzle holes.

Combustion air 24 is supplied by a blower (not shown) and is supplied to the combustion chambers 3, 4 through the air cushion chamber 19, the air valve 15.16 and the air passage 11.12. The fuel gas and combustion air supplied to the combustion chambers 3 and 4 are mixed to form an air-fuel mixture, which undergoes explosive combustion due to discharge from the spark plugs 13 and 14. Due to the explosion, the pressure in the combustion chambers 3 and 4 increases, causing air valves 15 and 16 and gas valves 1 to
7.18 is closed and the supply of fuel gas 25.26 and combustion air 24 is stopped. The high temperature combustion gas 27.28 passes through the thin tail pipes 5 and 6 and exchanges heat with water 29,
It flows into the exhaust cushion chamber 7.8 with decreasing temperature. This exhaust cushion chamber is provided with a partition plate 20 that divides the chamber. The partition plate 2o and the cylindrical partition plate 31 are fixed to the can body 33 with bolts 32.

The partition plate 20 is provided with a communication hole 21 near the bottom of the semi-cylindrical partition plate 31. The combustion gases 27, 28 are discharged through an exhaust pipe 22.23 which passes between the exhaust cushion chamber 7.8 and the cylindrical part of the semicircular partition plate 31 and is connected to the bottom plate 2.

When the combustion gases 27, 28 pass through the tail pipes 6, 6, the pressure inside the combustion chambers 3, 4 becomes negative pressure, and the air valves 15,
16, gas valves 17 and 18 open, combustion air 24,
Fuel gas 25,26 is drawn into the combustion chambers 3, 4. At that time, the high-temperature combustion gas in the combustion chamber causes the mixture of combustion air and combustion gas to explode. Then, similar explosions are repeated one after another, resulting in a pulse combustion state. When the pulse combustion state is reached, fuel gas 25° 26 and combustion air 24 are automatically sucked even if the blower is stopped.

When two pulse combustors are used for combustion, as described above, it is difficult to match the frequencies of each pulse combustor, resulting in a slight difference in frequency. This difference was the cause of the buzzing phenomenon in the combustion sound. When the exhaust cushion chambers are communicated with each other through the communication hole 21 as in the present invention, the pressure of the combustion gas 27, 28 in the two exhaust cushion chambers 7, 8 is stronger, which acts on the other one, forcing it to vibrate and synchronize it. In addition, the communication hole 21 is located near the bottom part 31, 32 of the semi-cylindrical partition plate, or the tail pipe 6, 6 has a high jetting speed of the combustion gas 27, 6, so it is easy to transmit static pressure. If the opening area of the communication hole 21 is less than 1/20 of the cross-sectional area of the tail pipes 6, 6, the effect of pressure vibration between the exhaust cushion chambers will be small, and if it is more than 1/10, the effect will be small. If the action is too strong and simultaneous ignition is not performed, it will adversely affect the ignition of the combustor due to the ignition delay. A large number of communication holes 21 may be provided, and in that case, the diameter thereof is preferably 3 or more inches in order to prevent shielding by foreign matter such as dew condensation.

Combustion gases 27 entering the exhaust cushion chamber 7.8
, 28 flows back to the outlet side of the tail pipes 5 and 6 from a chamber partitioned by the bottom cylinder part of the partition plate 20 and the semi-cylindrical partition plate 31 provided in the exhaust cushion chamber 7. Exhaust is discharged from the exhaust pipe 22.23 through the gap between the wall of ゜8 and the cylindrical part of the semi-cylindrical partition plate 31. At this time, the wall of the exhaust cushion chamber is effective because the gap is wide enough to ensure uniform discharge. Not only can it be used as a heat transfer surface, but also the bottom part of the semi-cylindrical partition plate can be used as a heat transfer surface for the combustion gas 27.
28 so that it does not shine directly onto the bottom 27, the pulsating energy of the combustion gas is relaxed and flows out through the bottom plate and the exhaust pipes 22 and 23 connected thereto, which is also effective in reducing noise. .

Furthermore, the partition plate 20 of the exhaust cushion chamber 8 can be provided at a position that is appropriately changed depending on the combustion amount of the two combustors. The combustion frequency must be set the same in the two combustors.

Although the above embodiment describes the case where two pulse combustors are arranged in parallel, two or more pulse combustors may be used.
However, they may not be arranged in rows, but may be arranged in a circle.

As described in detail of the invention, two pulse combustors are combusted in parallel, a common exhaust cushion chamber is used, a partition plate and a semi-cylindrical partition plate are combined in the exhaust cushion chamber to form a compartment, and a semi-cylindrical partition plate is used. By providing a communicating hole near the bottom of the tube, the following effects were obtained. ■Since the pressures of the two pulse combustors are more susceptible to interaction, the combustion gas flows uniformly on the wall of the exhaust cushion chamber due to the cylinder part of the cylindrical partition plate, which makes the thermal surface force more effective. It can be used. ■Since the exhaust cushion chamber is shared and two exhaust cushion chambers are formed using one partition plate, both configuration and manufacturing are simplified.

[Brief explanation of the drawing]

The figure is a sectional view showing the main part of a Noculus combustion device according to an embodiment of the present invention. 12... Pulse combustor, 3, 4... Combustion chamber, 56... Tail pipe, 7, 8...
... Exhaust cushion chamber, 20 ... Partition plate, 21 ... Communication hole, 31 ... Semi-cylindrical partition plate, 33 ... Can body.

Claims (1)

[Claims] A tail pipe is provided at one end of the combustion chamber, and pulse combustors are arranged in parallel with an air and gas supply path provided at the other end, and a cylindrical exhaust cushion chamber is commonly connected to each of the tail pipes. A pulse combustion device characterized in that a partially opened cylindrical partition plate is provided to partition a cylindrical chamber, and a partition plate is provided to partition the inside of the cylinder.