JPS646823B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an internal mixing type atomizer, and particularly to an internal mixing type atomizer suitable for atomizing high viscosity fluid.

Conventionally, as atomizers for atomizing various fluids such as fuel oil, steam atomization type, air atomization type, magnetic type, rotary cap type, emulsion type, collision type, ultrasonic type, etc. are known. However, at present, all of these atomizers can only be applied to low-viscosity fluids with a viscosity of 500 centipoise or less at 50°C. Particularly in boiler combustion, sufficient atomization is required, so the viscosity required of fuel oil is becoming even lower. In other words, when high viscosity fuel is atomized and burned in a burner that uses a conventional atomizer, the degree of atomization is poor, so some of the supplied fuel becomes coarse particles, causing the medium to scatter or the flame to become unstable. Problems such as Therefore, there are many fuels that have sufficient heat but cannot be used as boiler fuel because of their high viscosity.

An object of the present invention is to solve the above-mentioned conventional problems and provide an internal mixing type atomizer that can sufficiently atomize even highly viscous fluids.

In the internal mixing type atomizer of the present invention, the atomizing medium flow path is branched in the middle, one of which is a swirling path, and the atomized medium flow path is connected to the middle of this swirling path, so that the atomizing medium is A portion of the atomized fluid and the fluid to be atomized are supplied to the collision mixing chamber while being swirled.

Hereinafter, the present invention will be explained in more detail with reference to embodiments shown in the drawings.

FIG. 1 is a sectional view of an internal mixing type atomizer 10 according to an embodiment of the present invention.

This atomizer 10 includes an external nozzle 12 and intermediate nozzles 14 each fitted into the external nozzle 12.
and an internal nozzle 16. As shown in FIG. 2, the external nozzle 12 has a cylindrical shape with a large diameter and a bottom, and a collision mixing chamber 1 is provided on the bottom side.
8, and a mixed fluid ejection channel 20 that communicates the mixing chamber 18 with the outside.

As shown in FIG. 3, the internal nozzle 16 has a cylindrical shape with a small diameter and a bottom, the inside of which is a flow path 22 for the medium to be atomized, and a discharge hole 24 formed on the bottom side. . In addition, there is a rectangular recess 2 on the end surface of the bottomed side.
6 is formed, and a groove 28 extends from this recess 26 in a tangential direction to the inner circumferential surface of the intermediate nozzle 14 and reaches the outer circumferential surface of the inner nozzle 16. The discharge hole 24 opens near the connection between the groove 28 and the recess 26. Also, the internal nozzle 16 has a flange 30.
A through hole 3 is provided in this flange 30.
2 is drilled.

As shown in FIG. 4, the intermediate nozzle 14 has a short cylindrical shape with an inner hole 15, and the diameter gradually decreases toward one end in the axial direction, forming a tip opening 33 with a small diameter. This intermediate nozzle 14 is provided with a flange 34 . This flange 34 is also provided with a hole 36, similar to the flange 30 of the internal nozzle 16.

As shown in FIG. 1, in the atomizer 10, the intermediate nozzle 14 and the internal nozzle 16 are arranged coaxially with the external nozzle 12. Atomizing medium flow passages 38 and 40 are provided between the nozzle 16 and the external nozzle 12, respectively. Further, the intermediate nozzle 14 and the internal nozzle 16 are arranged so that their end surfaces are in contact with each other, and the groove 28 is covered with the end surface of the intermediate nozzle 14 to define a passage 28'. Intermediate nozzle 14
The inner hole 15) is in communication with the inner hole 15).

A portion of the atomizing medium (steam in this embodiment) supplied from the atomizing medium flow passage 38 enters the collision mixing chamber 18 through the passage 40 .

On the other hand, the fluid to be atomized (heavy oil in this embodiment) is supplied to the medium flow path 22 to be atomized and reaches the discharge port 24 . Therefore, the steam flowing from the passage 38 to the recess 26 through the passage 28' has a reduced pressure in the passage 28' because the passage area of the passage 28' is narrowed, and the pressure in the atomized medium flow passage 22 decreases. Heavy oil is easily discharged from the outlet 24 into the passage 28'.
Since the passage 28' extends in the tangential direction of the inner hole 15 of the intermediate nozzle 14, the heavy oil discharged into the passage 28' swirls together with steam inside the recess 26 and the inner hole 15 of the intermediate nozzle 14, and is combined with steam. It is mixed to form an emulsion, and some of it is atomized and the tip opening 33 is formed.
It enters the collision mixing chamber 18 from there. This collision mixing chamber 18
Steam is supplied from a passage 40 to the heavy oil, and the heavy oil is violently sheared and atomized by the steam from this passage 40. In particular, the heavy oil is swirled and supplied to the mixing chamber 18, and is already mixed with steam in the inner hole 15 of the intermediate nozzle 14 and emulsion or atomization has started. Atomization is significantly promoted.

The heavy oil is further jetted out from the mixed fluid jetting channel 20 and expanded and atomized.

In this way, according to the atomizer of the present invention, the fluid to be atomized is swirled together with the atomization medium, then violently sheared in the collision mixing chamber by the atomization medium supplied separately, and then jetted to the outside. The particles are then expanded and atomized, resulting in significant atomization. Therefore, it is possible to sufficiently atomize highly viscous fuel of 10,000 centipoise or more, which was impossible with conventional technology.

In addition, in burners using conventional atomizers, it was difficult to adjust the flame size when the fuel became highly viscous, but in burners using the atomizer of the present invention, the collision chamber and the jet flow path were difficult to adjust. By appropriate selection of
The flame size can be adjusted to suit the furnace, and a stable flame can be provided, so the range of boiler fuel selection is extremely wide. Furthermore, heavy oil, asphalt pitch, etc., which conventionally could not be converted into fuel due to their high viscosity, can also be used as boiler fuel.

In the above embodiments, steam and heavy oil are used as examples, but the present invention is not limited thereto, and various atomization media and fluids to be atomized may be employed.

According to various studies by the present inventors, the tip cross-sectional area of the atomized medium flow path 40 formed between the external nozzle 12 and the intermediate nozzle 14 is such that the flow velocity of the medium flowing therein is at or near the sonic speed. It has been found that it is preferable to be designed so that Also, the flow rate of the medium flowing through this flow path 40 and the intermediate nozzle 14
The flow rate of the medium flowing through is 60% vs. 40% or 80%.
% to about 20%, particularly around 70% to 30%, was found to be suitable. Furthermore, the cross-sectional area of the jet flow path 20 is designed so that the flow velocity of the mixed fluid is at or near the sonic speed, and the length of the flow path is 2 to 4 times its diameter. is preferred.

As described above, according to the present invention, an internal mixing type atomizer with extremely high atomization performance is provided.

[Brief explanation of drawings]

Fig. 1 is a sectional view of an atomizer according to an embodiment of the present invention, Fig. 2 is an axial sectional view of the external nozzle, Fig. 3A is an axial sectional view of the internal nozzle, and Fig. 3B is the same side view. FIG. 4 is an axial cross-sectional view of the intermediate nozzle. 12...External nozzle, 14...Intermediate nozzle, 1
6... Internal nozzle, 18... Collision mixing chamber, 20...
...Mixed fluid jet flow path, 22...Fluid flow path to be atomized,
38, 40...Atomization medium flow path.

Claims (1)

[Claims] 1. An atomized fluid flow path, an atomized medium flow path, a collision mixing chamber to which the atomized fluid flow path and the atomized medium flow path are connected, and a mixed fluid jet flow path connected to the collision mixing chamber. In the internal mixing type atomizer, the atomizing medium flow path is branched in the middle, and one of the branched flow paths is formed into a swirl path, and is merged with the to-be-atomized fluid flow path in the middle. An internal mixing atomizer characterized by: