JPH02259306A - Double pulse type combustion device - Google Patents

Abstract

PURPOSE:To provide a stable ignition as well as a silent ignition in a double pulse combustion device for a heating operation by a method wherein a pair of pulse burner exhausting pipes are in common with a combustion air supply pipe and a coefficient in forward direction of an air flow rate control valve is set higher than that of a reverse direction and each of igniting means is alternatively ignited. CONSTITUTION:A combustion air supply fan 17 is driven to supply combustion air to combustion chambers 10a and 10b through an air supply decoupler 16 and at the same time fuel is supplied from fuel supply pipes 13a and 13b, respectively. With such an arrangement, mixture gas which can be ignited instantaneously is generated within both combustion chambers 10a and 10b. Igniters 14a and 14b are alternatively energized by the controlling means 20 and a combustion is started from either one of them. In subsequent, the other combustion chamber starts to ignite and during this period, a combustion air and fuel for a next operation are supplied to a previous ignited combustion chamber. With such an arrangement, it is possible to perform a silent and stable ignition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a dual pulse combustion device used for space heating, heating, drying, etc.

(Prior Art) As a conventional dual pulse combustion device, a structure as shown in FIG. 4 is known. As shown in the figure, the combustion chamber 1a,
lb, and tail pipes 2a and 2b located downstream of this combustion chamber.
and a pulse burner consisting of combustion air flow rate control valves 3a, 3b located upstream of the combustion chamber, fuel supply pipes 4a, 4b, and ignition igniters 5a, 5b installed inside the combustion chamber. They are installed in parallel to form a double valve subburner.

Both pulse burners are commonly connected by an exhaust decoupler 6 provided downstream of the tail pipes 2a and 2b, and also commonly connected by a large supply air bluff upstream of the flow control valves 3a and 3b. , so that they acoustically interfere with each other.

A supply fan 8 used for supplying combustion air when starting the burner is provided upstream of the large supply air bluff. Further, each fuel supply pipe 4a, 4b is provided with a supply valve 9a, 9b.

As is well known, the combustion mode of this pulse combustion device is a type of unsteady combustion in which two air supply ignitions, explosions, and exhausts are repeated.In the above-mentioned double pulse burner, the two pulse burners are Because they interfere with each other, their phases are completely reversed, and for example, when one is in the explosion process, the other is in the air supply process, and combustion continues.

However, since the igniters 5a and 5b provided in the combustion chambers 1a and 1b are constantly energized by a circuit as shown in FIG. If the flame in one combustion chamber or both combustion chambers is blown away due to mutual interference due to a slight difference in ignition timing, the flame in one or both combustion chambers will be blown off, causing simultaneous ignition of both chambers again, and the situation will continue smoothly until the ambient temperature reaches a sufficient temperature. A proper combustion start-up could not be obtained.

(Problems to be Solved by the Invention) As described above, in the conventional dual pulse combustion device, the two combustion chambers simultaneously ignite at the time of ignition, causing a large noise, and the slight difference in ignition timing causing the two combustion chambers to ignite at the same time. Due to interference, one or both combustion chambers were extinguished, or both chambers were ignited simultaneously, making it impossible to achieve a smooth start of combustion.

The present invention was made in view of the above circumstances, and it
The purpose is to prevent simultaneous ignition in the room and provide stable and quiet ignition.

[Structure of the Invention] (Means for Solving the Problem) In order to achieve the above-mentioned object, the dual pulse combustion device of the present invention has a combustion chamber having a constant volume and a flow rate larger than the flow coefficient in the opposite direction. A pair of pulse burners equipped with a control valve, an exhaust means that commonly connects the downstream side of the tail pipe of each pulse burner of the pair of pulse burners, and an air supply pipe of the combustion chamber of each of the pulse burners that is commonly connected. The present invention is characterized in that it includes a supply means for supplying combustion air to each combustion chamber, an ignition means provided in each combustion chamber, and a control means for alternately igniting each of the ignition means at the time of ignition.

(Function) In the device configured in this way, when igniting, the control means alternately energizes the ignition means to ignite, so two
There is no simultaneous ignition in the two combustion chambers; combustion always starts in one combustion chamber, followed by combustion in the other combustion chamber, and the combustion process occurs and is maintained in opposite phases, resulting in two combustion chambers. Since the ignition takes place alternately in the chamber, stable and quiet ignition can be achieved.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
The figure is a configuration diagram of a dual pulse combustion device according to an embodiment of the present invention, which has a configuration in which two pulse burners of the same shape as the conventional one are arranged side by side, and combustion chambers 10a, 10b,
Tail pipes 11a and llb located on the downstream side of the combustion chamber and air supply pipes 12a and 12b located on the upstream side of the combustion chamber
Two pulse burners are arranged in parallel, each consisting of a fuel supply pipe 13a, 13b, and an igniter 14a, 14b, which is an ignition means installed in the combustion chamber, to form a double pulse burner.

Both pulse burners are connected in common by an exhaust decoupler 15, which is an exhaust means provided downstream of the tail pipes 11a and 11b, and also connected to an exhaust decoupler 15, which is an air supply means, provided on the upstream side of the air supply pipes 12a and 12b. They are connected in common by an air decoupler 16, so that they acoustically interfere with each other. A supply fan 17 is provided upstream of the supply air decoupler 16 and is used to supply combustion air when starting the burner. Also, each air supply pipe 12a.

12b and each fuel supply pipe 13a, 13b, combustion air flow control valves 18a, 18b and fuel flow control valve 1 are provided.
9a and 19b are provided.

The aforementioned combustion air flow rate control valves 18a, 18b and fuel flow rate control valves 19a, 19b have shapes that have different flow path resistance depending on the flow direction of fuel and air, and each combustion chamber 10a, 1
The direction in which air and fuel are supplied to 0b is installed so that the resistance is small (the flow coefficient in the forward direction is larger than the flow coefficient in the reverse direction). Also, a check valve or the like may be used instead of these valves.

Also, the above-mentioned igniter 14a for ignition.

14b is connected to a control means 20, and is controlled by this control means 20 to alternately energize the ignition igniters.

FIG. 2 is a circuit diagram showing a control means of a dual pulse combustion apparatus according to an embodiment of the present invention.

This circuit consists of a power supply 21. Step-up transformer 22. High voltage rectifying elements 23a, 23b, igniter 15a.

15b. The igniter 14a.

14b is provided within the combustion chambers 10a, 10b. The high-voltage rectifying elements 23 a and 23 b are connected so that their rectifying directions are different from each other. For this reason, the third
As shown in the diagram showing the ignition sequence of a dual pulse combustion device according to an embodiment of the present invention, it is possible to alternately control the energization of the two igniters 14a and 14b in response to AC power input. It is.

Next, the operation of the dual pulse combustion apparatus configured as described above will be explained.

At the time of ignition of this dual pulse combustion device, the combustion air supply fan 17 is driven, and the combustion air is supplied to the supply air decoupler 1.
6, the combustion chamber 10a.

10b. After igniting the igniter, fuel is supplied from the fuel supply pipes 13a and 13b. Since the air and fuel supplied to each combustion chamber 10a, 10b are equal in amount before ignition, an ignitable air-fuel mixture is formed in each combustion chamber 10a, 10b at the same moment. By alternately energizing the igniters 14g and 14b by the control means 20, combustion is always started in one of the combustion chambers 10a, and then in the other combustion chamber 10b. During combustion in this combustion chamber 10b, the combustion chamber 10a
Then, the next combustion air and fuel are supplied, and the igniter 14a is ignited to start the next combustion. In this way, combustion within the combustion chamber occurs in opposite phases, and combustion is repeated alternately. Therefore, the combustion exhaust gas pulsates in the tail pipes fla and ILb, and pressure fluctuations caused by combustion are canceled out in the exhaust decoupler 15, making it possible to achieve low noise and perform stable and quiet ignition.

Furthermore, when a variable frequency power source is used as the power source 21 in FIG.
It becomes possible to make the ignition period of b variable. Therefore, when igniting the dual pulse combustion device, ignition occurs alternately in the two combustion chambers, preventing simultaneous ignition of the two combustion chambers, and allowing quiet and stable ignition.

Further, the oscillation frequency of the dual pulse combustion device is acoustically determined by the combustion chamber volume, tail pipe length, etc., and changes depending on the ambient temperature. For this reason, when the ambient temperature is low (at the time of ignition in which pulse combustion is sustained only by ignition by the igniters 14a and 14b, the igniters L4a and 14b are controlled to be ignited alternately at the oscillation frequency of the pulse combustion device when the ambient temperature is room temperature). By controlling the device 20, quieter and more stable ignition can be achieved.

In addition, the ambient temperature becomes high from the start of ignition, and self-ignition becomes possible, causing the igniter 14a to ignite.

Until the igniter 14b is no longer needed, the oscillation frequency of the pulse combustion device changes as the ambient temperature changes, so a variable frequency power source is used as the power source 21 for the igniters 14a and 14b.

If the control device 20 controls the ignition frequency of 14b to be changed from the start of ignition in accordance with changes in the oscillation frequency of the pulse combustion device, quieter and more stable ignition can be achieved.

[Effects of the Invention] According to the present invention, at the time of ignition, the control means alternately energizes the ignition means to ignite, so combustion always starts from one of the combustion chambers without igniting the two combustion chambers at the same time. Subsequently, combustion begins in the other combustion chamber, and the combustion process occurs and is maintained in opposite phases, igniting alternately in the two combustion chambers, resulting in stable and quiet ignition.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a dual pulse combustion device according to an embodiment of the present invention, FIG. 2 is a circuit diagram showing a control means of a dual pulse combustion device according to an embodiment of the present invention, and FIG. The figure shows the ignition sequence of a dual pulse combustion device according to an embodiment of the present invention, FIG. 4 is a configuration diagram of a conventional dual pulse combustion device, and FIG. 5 shows a conventional dual pulse combustion device. FIG. 3 is a circuit diagram showing a control means of the pulse combustion device. 10a, b... Combustion chamber 11a, b... Tail pipe 2a, b... Air supply pipe 3a, b... Fuel supply pipe 4a, b... Igniter 5... Exhaust decoupler 6...・Air supply large bluff...Supply fans $a, b...Air flow rate control valves 9a, b...Fuel flow rate control valve 0...Control means 1...Power source 2...Step-up transformer 3a, b ...High voltage rectifier

Claims (3)

[Claims] (1) A combustion chamber having a constant volume, a tail pipe located on the downstream side of the combustion chamber, and a fuel supply pipe and an air supply pipe located on the upstream side of the combustion chamber; a pair of pulse burners equipped with a flow rate control valve larger than a flow rate coefficient in the opposite direction; an exhaust means that commonly connects the downstream side of the tail pipe of each pulse burner of the pair of pulse burners; and combustion of each of the pulse burners. A supply means for commonly connecting the air supply pipes of the chambers and supplying combustion air to each combustion chamber, an ignition means provided in each of the fuel chambers, and a control means for alternately igniting each of the ignition means at the time of ignition. A dual pulse combustion device characterized by comprising: (2) The dual pulse combustion apparatus according to claim 1, wherein the control means alternately ignites the ignition means at a frequency near the resonance frequency of the pulse combustion apparatus at room temperature. (3) The control means alternately ignites the ignition means by changing the ignition frequency of the ignition means from the start of ignition until steady pulse combustion is obtained. Pulse combustion device.