JPH0345282B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a liquid fuel combustion device that atomizes and burns liquid, and such a device can be used in industrial boilers, heating furnaces, consumer boilers, space heaters, etc. used.

Conventional configuration and its problems A conventional swirl-type pressure spray burner will be explained.

FIG. 1 shows an example of a rotating pressure spray burner.
Reference numeral 1 denotes a nozzle, which is provided inside the blower tube 2. Combustion air from the blower 3 is supplied to the combustion section through the blower tube 2 while being swirled by the swirling vane 4 provided at the opening at the tip thereof. On the other hand, the spray ejected from the nozzle 1 has a spray angle of approximately 40 to 90 degrees, and mixes with the combustion air to form a conical flame.
The disadvantage of this method is that since the spray and air travel in approximately the same direction, the flow velocity in the combustion section where fuel and air coexist is high, and the flame tends to lift.
In order to prevent this drawback, the swirling vanes 4 create a circulating flow of air to create a flame-holding mechanism.
This swirl vane 4 is used to improve the poor mixing of air and spray flowing in approximately the same direction, and to improve the difficulty of combustion in a pressure swirl nozzle with a particle size of 50 to 60 microns. This gives the flame a strong swirl, making it extremely noisy.
As described above, the conventional method requires a flame-holding mechanism and a means for forcibly mixing the spray and air, making the structure complicated and generating a large amount of noise.

Purpose of the invention The purpose of the present invention is to atomize liquid with a simple structure,
This aims to realize a low-noise liquid fuel combustion device that does not require the generation of forced turbulent air by increasing the vaporization rate of fuel to make it easier to burn, and by making it easier to mix fuel and air. Another purpose is to obtain a simple structure that does not have a flame-holding mechanism that has been intentionally used in the past.

Structure of the Invention The present invention sends pressurized fuel oil to a nozzle to generate a linear jet stream. The jet flow is initially a smooth flow, but gradually becomes an oscillating flow and then a split flow. The impactor of the present invention is provided in the smooth flow region closest to the nozzle. The reason for this is that the split flow region and the oscillating flow region are unstable and the distance between the nozzle and the impactor becomes long, making it difficult to accurately position the impactor.

After the liquid flow collides, it spreads as a liquid film flow in an approximately disk shape, and particles are generated from the tip of the liquid flow by splitting. The split fine particles spread as a substantially disk-shaped spray film on an extension of the liquid film.

Then, a nozzle is provided in a combustion air blower tube, and a collision body is provided outside the opening of this blower tube,
The key point of the present invention is to place the disk-shaped thin spray film facing the combustion air flow.

That is, since the combustion air hits the surface of the spray film (nozzle direction plane) at right angles, the air velocity rapidly decreases at the surface of the spray film. At the same time, air is supplied to the entire spray film, and the air easily enters the spray.

Furthermore, since the spray film is thin and disc-shaped, air is easily mixed into the entire spray.

Further, since the particle size obtained by this collision atomization mechanism is extremely fine, the vaporization and combustion rate are extremely fast.The combustion phenomenon under such a situation will be described below.

Since the air velocity on the surface of the spray film is slowed down, the flame at the interface between the air and the spray film is easily stabilized. That is, this is because a region with a flow velocity lower than the combustion velocity was formed on the surface of the spray film. In other words, the spray film functions as a flame-holding plate.

In addition, since the combustion air easily enters the spray, the air and fuel are mixed well and soot is hardly produced.
Further, since the particle size is small, the flame stabilization generated at the interface is a blue flame, which has the effect of preventing soot as a combustion intermediate product from adhering to the collision body.

Description of examples An embodiment of the present invention will be described with reference to FIG.

Reference numeral 1 denotes a single-hole nozzle, which is provided at the center inside the blower tube 2 . Combustion air is supplied from the blower 3 to the combustion section through the opening 5 while cooling the nozzle 1 inside the blower tube 2 .

On the other hand, the liquid fuel pressurized by the pump 6 is ejected from the outlet of the nozzle 1 and hits the collision body 8 having a circular collision surface 7 located outside the opening 5 while maintaining a linear smooth flow. This collision body 8 is a support body 9
The nozzle 1 is fixed to the nozzle 1 by a screw, and is adjusted so that the liquid flow hits the center of the collision surface 7.

After the collision, the liquid flow spreads as a substantially disc-shaped liquid film flow and a spray flow. This spray stream is actually an umbrella-shaped disk as shown in the figure, and its tip is spread downstream by the combustion air. When ignited by an igniter (not shown) in such a state, a flame is generated in the middle of the spray film, that is, in the portion where the spray spreads in a substantially disk shape. This flame is a blue flame generated at the interface between the above-mentioned spray film surface and air. This flame becomes a stable flame and rapidly vaporizes the surrounding spray, so the spray disappears and becomes a mixture of gas and air and their combustion products, which change the direction of the flame downstream. .

On the other hand, a negative pressure is generated on the surface of the spray film (in the opposite direction of the nozzle 1) because the gas near the collision surface 7 is transported toward the outer circumference of the spray film by the spray flow, and the air is exhausted into this negative pressure area. Alternatively, the flame is recirculated to promote vaporization of the spray from the back side of the spray film.

Next, another embodiment will be described with reference to FIG.

Nozzle 1 and opening 5 of blow tube 2 surrounding it
and the collision body 8, a rectifying plate 12 having a large number of combustion air holes 10 and a liquid flow through hole 11 in the center.
has been established. Combustion air hole 1 of the baffle plate 12
0 rectifies the air in the blower tube 2 to further reduce the turbulence of the combustion flame, resulting in lower noise.Compared to Fig. 2, the high-speed combustion air from the small hole rushes into the spray film, causing the spray to form. Improves air mixing and promotes combustion. Further, even if the swirl vane or other flame stabilizing mechanism described in the conventional example is added, it does not impair the effects of the present invention and can further improve the performance. It is also possible to provide additional air.

Effects of the Invention The liquid fuel combustion device using the present invention does not lose any of the advantages of heavy oil resistance and instant ignition/extinguishing properties that are characteristics of spray combustion, and the spray itself has the effect of a flame-holding plate. A device with a simple structure can be realized. In addition, since the spray with small particle size resulting from collisional atomization and the combustion air can be mixed without turbulence, it has low noise, an effect that could not be achieved with conventional simple burners. This effect is further enhanced by the embodiment shown in FIG.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a conventional example, FIG. 2 is a block diagram showing one embodiment of the present invention, and FIG. 3 is a block diagram showing another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Nozzle, 2... Blower tube, 4... Swirl vane, 5... Opening part, 8... Collider, 12... Current plate.

Claims (1)

[Claims] 1. A linear liquid stream is ejected from the tip of a single-hole nozzle, and a colliding object is ejected from the linear part of the liquid stream (the columnar part before becoming a droplet array), facing the liquid stream. A liquid fuel combustion device, wherein the single-hole nozzle is provided in a blower tube that communicates with a blower to supply combustion air to a combustion section, and the collision body is provided outside an opening of the blower tube. 2. The liquid fuel combustion device according to claim 1, further comprising a rectifying plate having a liquid flow through hole in the center and a large number of combustion air holes around the periphery, provided between the opening of the blast tube and the collision body.