JPH0125962B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid fuel vaporization burner, that is, a burner that gasifies and burns liquid fuel such as petroleum.

Conventionally, there are various types of liquid fuel vaporization type burners, but the liquid fuel gasification methods can be roughly divided into the following two types.

Two types of fuel are vaporized by dropping liquid fuel onto a vaporization surface that has been preheated and heated using an electric heater or other heat source, and two types are those that vaporize liquid fuel by dropping it onto a vaporizing surface that has been preheated using an electric heater or other heat source, and those that vaporize liquid fuel by supplying the fuel to a rotating disk or the like and scattering the fuel using centrifugal force. It is brought into contact with the vaporized surface, vaporized, mixed with air, and then combusted.

However, with these conventional methods, it is necessary to preheat the vaporizing surface, which requires time to burn, and it is difficult to control the temperature of the vaporizing surface. There are disadvantages such as adhesion of the gas, which impairs good vaporization and deteriorates the combustion state, and the structure is complicated because the vaporizing surface and the combustion part are separated.

The present invention solves the above problems, simplifies the structure by eliminating the need for a special heating source, shortens the initial rise time, and enables stable blue flame combustion.

The basic structure of the present invention to achieve the above object is to provide a baffle plate having a convex shape toward the inside of the cone and a few small holes at the outlet of the burner cone, and supply air at high speed around the nozzle. An air outlet is provided, and by using the suction force generated by blowing out the air and the rectification of the air by the rectifying plate, high-temperature combustion gas is sucked into the burner cone from the combustion gas suction port drilled at the rear of the burner cone, and fuel gas is drawn into the burner cone. In addition, the burner cone is made of water-absorbing porous ceramic, and the front half of the cone is expanded forward at an angle slightly narrower than the spray angle of the nozzle, so that the fuel sprayed from the nozzle is By causing the spray to collide with the burner cone, the unburned liquid that hits the burner cone temporarily soaks into the burner cone, where it is evaporated using the heat of the cone heated in the combustion chamber and released as steam. At the same time, a stable flame is formed at the opening at the front end of the burner cone using the high-temperature gas staying in the recess behind the baffle plate as an ignition source.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In the figure, reference numeral 1 denotes a combustion chamber, and an air outlet 5 is opened in a side wall 1' of the combustion chamber, and a burner cone 3 is provided surrounding this outlet 5.

The air outlet 5 is formed to protrude into the combustion chamber 1 and communicates with a blower fan 9 on the outside of the combustion chamber 1.

In addition, the air outlet 5 gradually reduces its passage area toward the front to form a conical shape so that air can be blown out at high speed, and the opening at the front end is adjusted appropriately to obtain a stable air flow without turbulence. It is formed into a straight cylindrical shape with a certain length and diameter. The flow of air from the air outlet 5 is strongly related to the suction of high-temperature combustion gas, the stabilization of the flame at the outlet of the burner cone 3 and the baffle plate, and the combustion noise. An oil feed pipe 10 is inserted through the center of the air outlet 5 so as to hold the fuel spray nozzle 2 provided at its tip so as to slightly protrude from the front end opening of the air outlet 5.

The oil supply pipe 10 connects to an oil supply source 11 outside the combustion chamber 1.
A pressurizing pump 12 is provided in the middle.

The fuel spray nozzle 2 has a conventionally well-known structure, is formed so that the spray angle is, for example, approximately 60 degrees, and is provided so as to slightly protrude from the tip of the air outlet 5 and be located within the burner cone 3. .

Further, an igniter 13 is disposed close to the fuel spray nozzle 2 in a position that does not obstruct the flow of air from the air outlet 5.

The burner cone 3 is made of water-absorbing porous ceramic, and the rear half has a straight cylindrical shape, and the front half has a conical shape that expands forward at an angle slightly narrower than the spray angle of the fuel spray nozzle 2. It is attached to the side wall 1' of the combustion chamber 1 coaxially with the fuel spray nozzle 2 and the air outlet 5, surrounding the fuel spray nozzle 2 and the air outlet 5 so that the sprayed fuel sprayed from the spray nozzle 2 collides with the inner peripheral surface of the expanded portion 3a.

Further, the burner cone 3 has a fuel gas suction port 6 in the straight cylindrical portion 3b such that the opening area thereof becomes a necessary area to achieve suction of an appropriate amount of combustion gas. A rectifying plate 4 is provided at the opening at the front end.

The rectifier plate 4 may be made of metal such as stainless steel, but may also be made of water-absorbing porous ceramic and integrally formed with the burner cone 3 into the shape shown in the figure.

That is, the current plate 4 is formed into a conical or hemispherical shape with an open bottom, and its convex surface is connected to the burner cone 3.
It is provided coaxially with the burner cone 3 facing inward, and when it is integrally molded with the burner cone from ceramic, for example, the front end is connected to the front end of the burner cone 3 at an appropriate location in the circumferential direction.
Continuous through.

The baffle plate 4 is inserted into the burner cone 3 with its front end located at almost the same position as the front end of the burner cone 3, and between both 3 and 4 is provided a suction of combustion gas. The mixed gas flow path 8 is formed with an appropriate spacing effective for promoting the mixing of vaporized fuel and air without hindering the mixing.

Further, an appropriate number of small holes 7 are bored in the current plate 4.

Thus, such a burner blows out air supplied from the blower fan 9 from the air outlet 5 along the fuel spray nozzle 2. At this time, air is blown out from the air outlet 5 at a very high speed due to the shape of the air outlet 5, so the surrounding area becomes negative pressure, and together with the rectification of the air flow by the rectifier plate 4, the air in the combustion chamber 1 is The combustion gas is sucked into the burner cone 3 through the suction port 6. As a result, a circulating flow 1 passes from the air outlet 5 through the mixed gas flow path 8 between the burner cone 3 and the baffle plate 4, and reaches the inside of the burner cone 3 from the combustion gas suction port 6.
5 occurs.

Next, sparks fly from igniter 13. When liquid fuel such as kerosene is sprayed from the fuel spray nozzle 2 in this state, a mixture of the sprayed fuel and air is formed. At the same time, the spark from the igniter 13 ignites this mixture, and a yellow flame is formed in the center of the burner cone 3.

After ignition, hot combustion gas is sucked into the burner cone 3 from the combustion gas suction port 6 by the circulation action,
Instantly gasifies sprayed fuel.

Mixing of the gasified fuel and air is promoted by the mixing action of the mixed gas flow path 8 between the burner cone 3 and the baffle plate 4 provided at the center of the outlet of the burner cone 3. On the other hand, burner cone 3
The yellow flame inside sucks in the combustion gas from the fuel gas suction port 6, and at the same time moves to the outlet of the burner cone 3, where the mixture is ignited and completely combusted. Therefore, combustion is blue flame combustion.

This movement of the combustion position causes combustion gas with a low oxygen concentration to be sucked in, resulting in a lack of oxygen near the wall inside the burner cone 3, making it impossible to maintain flame adhesion in this area, and causing the fuel gas and air at the outlet of the burner cone 3 to become insufficient. This is achieved by moving the flame into a zone where it mixes with the

As a result, the flame is not formed in a closed space, but at the open end, resulting in quieter combustion noise.

In order to achieve the movement of the combustion position, it is necessary to suppress the mixing of the combustion gas with a low oxygen concentration sucked into the burner cone 3 and the combustion air, and this is due to the length and diameter of the straight part of the air outlet 5. is closely related to the diameter of the straight portion 3b of the burner cone 3 and the area of the combustion gas suction port 6.

On the other hand, unburned particles of fuel that are not gasified by the combustion gas collide with the inner circumferential surface of the expanded portion 3a of the burner cone 3, but since this is made of water-absorbing porous ceramic, the fuel is absorbed into the ceramic. Once it is inhaled and held, it is immediately evaporated and gasified by the heat of the burner cone 3 heated by combustion, and ignited at the cone outlet.

If the current plate is made of water-repellent ceramic, the same effect as burner cone 3 will cause
Combustion becomes even better as the unburned particles that hit the current plate are gasified.

Furthermore, since the concave portion of the baffle plate 4 becomes a negative pressure zone of the air, high-temperature combustion gas remains in this portion, and this high-temperature gas fuels the mixed gas flow path 8 between the cone 3 and the baffle plate 4. Serves as an ignition source for gas and air mixtures.

As a result, blue flames are emitted from the small holes appropriately drilled in the rectifier plate 4 and radially from the entire circumference of the end portion of the rectifier plate 4.

By providing a place at the outlet of the burner cone 3 in which the high-temperature gas remains, a stable flame can be formed at the outlet of the burner cone 3, and there is no disturbance of the flame.

Therefore, the baffle plate 4 has the functions of promoting the mixing of air and fuel gas, rectifying the airflow, serving as an ignition source by flame holding, and as an intake gasification surface for the atomized fuel.

Since the present invention has the above configuration, it has the following advantages.

(1) By forming the burner cone and, in some cases, the baffle plate installed at its front end opening, from water-absorbing porous ceramic, unburned liquid is temporarily sucked into the ceramic and then released as steam. The combustion gas is sucked into the burner cone, and the heat instantly gasifies the fuel sprayed from the nozzle.
Moreover, since the mixing of the gasified fuel and air is promoted by the baffle plate, complete combustion can be achieved at the burner cone outlet.As a result, the combustion becomes blue flame combustion with no red flame, and no soot is generated. It is possible to suppress the generation of carbon monoxide, reduce the excess air ratio, and improve combustion efficiency.

Also, since the length of the flame is short, the combustion chamber can be made smaller.

(2) The current plate is formed into a conical or hemispherical shape with an open bottom, and is installed at the burner cone outlet with its convex face facing inward, so that high-temperature combustion gas remains in the concave portion of the current plate. This serves as an ignition source for the fuel gas, which ignites toward the open end of the burner cone, making it possible to form a stable flame at the outlet of the burner cone, as well as flame formation occurring at the open end of the burner cone. The combustion noise is small and quiet.

(3) Since the fuel is gasified by the burner's own combustion heat, no special heating source is required and the start-up time is quick.

(4) Since the burner cone is made of ceramic, it has excellent heat resistance and improved durability.

(5) When the burner cone and current plate are made of ceramic, they can be integrally molded, resulting in a simpler structure and easier manufacturing.

(6) Combustion air is drawn into the burner cone and the heat is used to gasify the atomized fuel, so gasification occurs quickly and combustion is quick and stable.

(7) Since the burner cone is made of water-absorbing ceramic, even if the temperature of the cone itself rises and reaches a temperature considerably higher than the boiling point of the fuel, unburned fuel that hits the cone becomes granular. Does not generate tar etc.

Therefore, gasification of the fuel is not hindered by tar adhesion to the burner cone.

[Brief explanation of drawings]

The drawing is a schematic diagram of a liquid fuel vaporizing burner showing an embodiment of the present invention. 1... Combustion chamber, 2... Fuel spray nozzle, 3...
Burner cone, 4... Current plate, 5... Air outlet, 6... Combustion gas suction port, 7... Hole, 8... Mixed gas flow path.

Claims (1)

[Claims] 1. A fuel spray nozzle inserted into the combustion chamber, a burner cone surrounding the nozzle and provided coaxially with the nozzle so that the sprayed fuel sprayed from the fuel spray nozzle collides with the inner peripheral surface, and a front end opening of the burner cone. The burner cone is made of water-absorbing porous ceramic, and the front half is connected to the fuel spray nozzle. The second half is formed into a straight cylindrical shape, and combustion gas suction ports are appropriately opened in the circumferential direction of the straight cylindrical shape. The porous ceramic is formed into a conical or hemispherical shape with an open bottom, and a number of small holes are provided at appropriate locations.
The convex surface faces the inside of the burner cone, and a mixed gas flow path is provided at an appropriate interval between the convex surface and the burner cone. A liquid fuel vaporization burner formed into a straight cylindrical shape.