JPH02150605A - Pulse burner - Google Patents

Abstract

PURPOSE:To make a force of combustion variable in a wide range while keeping the combustion efficiency at a high level by a method wherein the quantity of a fuel supplied to a combustion chamber of the main body of a burner is made variable and the flow rate of air for combustion flowing into the combustion chamber is controlled in accordance with the quantity of the fuel supplied to the combustion chamber. CONSTITUTION:In a pulse burner, a fan 11 is stopped when the degree of opening of a fuel flow control valve 10 is the standard one. When the degree of opening of the fuel flow control valve 10 is increased so as to increase a force of combustion, an opening degree signal is sent to a fan control element 12. Based on this signal, the fan control element 12 makes the fan 11 rotate normally and controls the number of rotations thereof to be the one corresponding to the degree of opening, i.e. the number of rotations corresponding to the quantity of a fuel flowing into a combustion chamber 1. When the degree of opening of the fuel flow control valve 10 is decreased below the standard one so as to reduce the force of combustion, the fan control element 12 makes the fan 11 rotate reversely to make it correspond to the reduced quantity of the fuel flowing into the combustion chamber 1 and controls the number of rotations to be corresponding to the reduced quantity. Accordingly, combustion in the amount of combustion corresponding to the quantity of the fuel is attained with the air ratio fixed substantially.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a pulse burner that allows a wide variable range of combustion amount.

(Prior Art) A pulse burner is normally constructed as shown in FIG. That is, a combustion chamber 1 that burns a mixed gas of fuel and combustion air in a pulsed manner, a tail pipe 2 that exhausts combustion gas, and a combustion chamber provided in an air supply path that supplies air to the combustion chamber 1, for example, A nozzle-shaped flow control valve 3 whose flow coefficient in one direction is larger than a flow coefficient in the opposite direction, an air supply decoupler 4 connected to the upstream side of the flow control valve 3 to reduce noise, and air flowing into the combustion chamber 1. Fuel control valve 5 that limits the amount of fuel
, an igniter 6 for ignition, an exhaust decoupler 8 connected to the downstream side of the tail pipe 2, and a small-capacity fan 9 connected to the upstream side of the supply air decoupler 4. In addition,
In the figure, 7 indicates a frame sensor.

In such a pulse burner, intermittent explosive combustion occurs within the combustion chamber 1, resulting in pressure fluctuations and
Air and fuel are self-suctioned when the internal pressure becomes lower than atmospheric pressure. Therefore, in a pulse burner, the fan 9 can usually be stopped during steady combustion, which is one of the advantages.

Incidentally, recently, it has become desirable to incorporate pulse burners into various systems, and as a result, there has been a demand for pulse burners whose combustion power can be varied significantly. However, the range of variable capacity of the pulse burner cannot be freely controlled because air is self-suctioned.

FIG. 6 is a diagram showing the relationship between the ratio of the actual input to the standard input of a conventional pulse burner and (CO/CO2). As you can see from this figure, increasing or decreasing the amount of combustion results in air shortage.

There was a problem that there was too much air and the combustion amount could only be varied within a very narrow range.

(Problems to be Solved by the Invention) As described above, the conventional pulse burner has a problem in that it is not possible to have a wide variable range of combustion power while maintaining efficient combustion.

SUMMARY OF THE INVENTION An object of the present invention is to provide a pulse spanner that can vary combustion power over a wide range while maintaining high combustion efficiency.

[Configuration of the Invention (Means for Solving the Problems) In order to solve the above problems and achieve the objectives, the pulse burner according to the present invention has a method of varying the amount of fuel supplied to the combustion chamber of the pulse burner main body. and differential pressure control means for varying the difference between the pressure within the combustion chamber and the pressure at the air intake of the feed pulse burner body in accordance with the amount of fuel supplied to the combustion chamber. Item 1).

The pulse burner according to the present invention also includes means for varying the amount of fuel supplied to the combustion chamber of the pulse burner main body, and combustion air flowing into the combustion chamber according to the amount of fuel supplied to the combustion chamber. (Claim 4).

(Function) In the invention of claim 1, when the amount of fuel supplied to the combustion chamber is increased, the pressure at the air intake port of the combustion chamber is increased in accordance with this increased amount. Therefore, the difference between the pressure inside the combustion chamber and the pressure at the air intake port increases, and the amount of combustion air flowing into the combustion chamber increases. Also, when the fuel supplied to the combustion chamber is reduced, the pressure at the air intake port decreases correspondingly. Therefore, the difference between the pressure inside the combustion chamber and the pressure at the air intake port becomes smaller, and the amount of combustion air flowing into the combustion chamber is reduced. In this way, since the amount of air flowing into the combustion chamber can be varied in accordance with the amount of fuel to be supplied, the combustion amount can be varied over a wide range while keeping the air ratio constant.

Furthermore, in the second aspect of the invention, the amount of air flowing into the combustion chamber changes depending on the amount of fuel supplied to the combustion chamber. Therefore, in this case as well, the combustion variable range can be widened while keeping the air ratio constant.

(Example) Examples will be described below with reference to the drawings.

FIG. 1 is a partially cutaway side sectional view of a pulse burner according to an embodiment of the present invention. In the figure, the same parts as in FIG. 5 are given the same reference numerals.

This pulse burner is connected to a combustion chamber 1 that causes fuel and combustion air to react, a tail pipe 2 that exhausts the gas that has reacted in the combustion chamber 1, and an air supply path that supplies air into the combustion chamber 1. and an air supply decoupler 4 connected to the upstream side of the air flow control valve 3 to reduce noise.
A fuel valve 5 , a fuel flow control valve 10 connected to the upstream side of the fuel valve 5 , an igniter 6 for ignition, an exhaust decoupler 8 connected to the downstream side of the tail pipe 2 , and an air supply decoupler 4
a fan 11 connected to the upstream side of the fan 11 and capable of forward and reverse rotation;
The fan control unit 12 receives an opening signal of the fuel flow control valve 10 and controls the rotation direction and rotation speed of the fan 1 based on the received signal.

The fan control unit 12 stops the fan 11 when the fuel flow control valve 10 is at the standard opening, and stops the fan 11 when the opening is greater than the standard opening.
The fan 11 is rotated in the forward rotation direction at a rotation speed corresponding to the amount of increase in the opening degree, and when the opening degree decreases from the reference opening degree, the fan 11 is rotated in the reverse direction at a rotation speed corresponding to the amount of decrease in the opening degree. control so that Note that 7 in the figure indicates a frame sensor.

Next, the operation of the pulse burner configured as described above will be explained with reference to FIG. 2 as appropriate. Note that FIG. 2 is a diagram showing the pressure of the combustion chamber 1 and the air intake port of the combustion chamber 1.

In the pulse burner configured as described above, the opening degree of the fuel flow control valve 100 is the reference opening degree, that is, the fan 11 is stopped during steady combustion. At this time, the pressure at the air intake port 13 of the combustion chamber 1 is the pressure Po on the vertical axis shown in FIG. The pressure P within the combustion chamber 1 changes over time as shown in the figure. Therefore, the pressure P in the combustion chamber 1 is the pressure P at the air intake port 13 of the combustion chamber 1. , i.e. between times t1 and t4, combustion air flows into the combustion chamber 1 via the air flow control valve 3.

Here, when the opening degree of the fuel flow control valve 10 is increased in order to increase the combustion power of the pulse burner, this opening degree signal is sent to the fan control section 12. Based on this signal, the fan control unit 12 rotates the fan 11 in the normal direction and controls the rotation speed to correspond to the opening degree, that is, the rotation speed to correspond to the amount of fuel flowing into the combustion chamber 1. As a result, air intake 1
The pressure of 3 is pressure P. The pressure changes from P to P. Therefore, a combustion chamber 1 is supplied at a time t when the pressure P in this combustion chamber 1 becomes lower than the pressure P1 at the air intake.

~ time t5, combustion air flows in via the air flow control valve 3. That is, an amount of combustion air will flow into the combustion chamber 1 in accordance with the amount of fuel flowing into the combustion chamber 1, so that the air ratio will be approximately constant and combustion will be performed with a high combustion amount.

Furthermore, when the opening degree of the fuel flow control valve 10 is decreased from the reference opening degree in order to reduce the combustion power of the pulse burner, the fan control unit 12 causes the fuel flow control valve 10 to decrease in opening degree, that is, the flow of fuel into the combustion chamber 1 is reduced. fan 1 in response to the decrease in fuel amount.
1 is reversed, and the rotational speed is controlled to correspond to the amount of decrease. As a result, the air intake pressure 13 becomes the pressure P2. Therefore, the pressure inside the combustion chamber 1 becomes lower than the pressure P1 at the air intake port at the time t.
2 to time t3, combustion air flows in via the air flow control valve 3. That is, the amount of combustion air flowing into the combustion chamber 1 is smaller than that during steady combustion, and moreover, the amount of combustion air flowing into the combustion chamber 1 corresponds to the amount of fuel flowing into the combustion chamber 1. Therefore, in this case as well, the air ratio is approximately constant and combustion is performed in an amount corresponding to the amount of fuel.

FIG. 3 is a diagram showing the (Co/C02) characteristic with respect to the ratio of actual power corresponding to the standard input of this pulse burner.

The dashed curve shows the characteristics of a conventional pulse burner,
The solid curve shows the characteristics of the pulse burner according to the present invention. As can be seen from this figure, compared to conventional pulse burners, this pulse burner can greatly vary the combustion capacity while keeping the air ratio constant.

Note that the present invention is not limited to the embodiments described above. For example, a fan 11 is connected upstream of the air supply decoupler 4 as an element for controlling the differential pressure, which is the difference between the pressure in the combustion chamber 1 and the pressure at the air intake port of the combustion chamber 1. As shown in FIG. 4, by connecting the fan 11 downstream of the exhaust decoupler 8 and controlling it with the fan control section 12, the same effects as in the previous embodiment can be obtained. Furthermore, the amount of air flowing into the combustion chamber may be varied in accordance with the amount of fuel supplied. Furthermore, the present invention can also be applied to a coupled pulse burner that can reduce noise.

[Effects of the Invention] According to the present invention, the differential pressure control means for controlling the difference between the pressure at the combustion air intake port and the pressure in the combustion chamber according to the amount of fuel flowing into the combustion chamber is provided. The amount of air supplied can be varied in response to an increase or decrease in the amount of combustion air, and the range of variable combustion amount can be greatly expanded while keeping the ratio of fuel to combustion air substantially constant.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view of a pulse burner according to an embodiment of the present invention, FIG. 2 is a diagram for explaining the relationship between the pressure in the combustion chamber and the pressure in the air intake port, and FIG. 4 is a partially cutaway side view of a pulse burner according to another embodiment of the present invention; FIG. The figure shows the configuration of a conventional pulse burner, and FIG. 6 is a diagram for explaining the combustion amount variable range of the conventional pulse burner. 1... Combustion chamber, 2... Tail pipe, 3... Flow rate control valve, 4
...Air supply decoupler, 6...Igniter, 7...
Frame sensor, 8...Exhaust decoupler, 11...
Fan, 10...Fuel flow control valve, 12...Fan control unit, 13...Air intake port. Applicant's agent Patent attorney Takehiko Suzue - 〇 (to) LCLQ- 田

Claims (4)

[Claims] (1) A pulse burner main body, a fuel supply means for supplying fuel to the combustion chamber of the pulse burner main body, an air supply means for supplying combustion air to the combustion chamber, and exhaust gas reacted in the combustion chamber. a tail pipe, a means for varying the amount of fuel supplied to the combustion chamber, and a means for adjusting the pressure in the combustion chamber and the pulse burner body according to the amount of fuel supplied to the combustion chamber; 1. A pulse burner comprising differential pressure control means for varying the difference between the pressure and the pressure at the air intake port. (2) The pulse burner according to claim 1, wherein the differential pressure control means is constituted by an air supply control system that controls the outlet pressure of the air supply means. (3) The differential pressure control means is configured with an exhaust gas flow rate control system that controls the flow rate of exhaust gas exhausted from the tail pipe according to the amount of fuel supplied to the combustion chamber. pulse burner. (4) A pulse burner main body, a fuel supply means for supplying fuel to the combustion chamber of the pulse burner main body, an air supply means for supplying combustion air to the combustion chamber, and exhaust gas reacted in the combustion chamber. A pulse burner equipped with a tail pipe, a means for varying the amount of fuel supplied to the combustion chamber, and controlling a flow rate of air flowing into the combustion chamber according to the amount of fuel supplied to the combustion chamber. A pulse burner comprising air supply amount control means.