JPH06416A - Liquid jet nozzle - Google Patents

Abstract

(57) [Abstract] [Purpose] A large turbulence is generated in the jet flow, and the liquid is mixed well with air to obtain a uniform concentration distribution. In a liquid jet nozzle having a bag portion 2 formed at the tip of a nozzle body 1 and a nozzle hole 3 formed in the nozzle body 1 so as to open from the bag portion 2 to the outside, the nozzle hole 3 is , A plurality of branch holes 3a and one merge hole 3b that merges with the plurality of branch holes 3a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is suitable for use in fuel injection valves for internal combustion engines, burners for combustion equipment such as boilers, and liquid atomizers for painting and drying. (Including the liquid substance of (1)) is well mixed with air to obtain a uniform concentration distribution.

[0002]

2. Description of the Related Art In a conventional liquid ejecting nozzle, as shown in FIG. 4, a bag portion 2 is formed at the tip of a nozzle body 1, and a single or a plurality of injection holes 3 that open to the outside from the bag portion 2 are formed. By the sliding of the needle valve 4, the pressurized liquid is jetted from the jet hole 3 through the liquid supply path 5 and the bag portion 2. The injection hole 3 has a substantially cylindrical shape, and its length is the thickness of the tip of the nozzle body 1.

The inventor of the present invention conducted an experiment for observing the concentration distribution inside the spray using the liquid jet nozzle. FIG. 5 is a schematic configuration diagram of the experimental apparatus. 11 is a high pressure container, 12 is a window, 13 is an injection nozzle, 14 is a vacuum pump, 15 is a nitrogen gas cylinder, 16 is an image conversion camera, 17 is a fuel supply device, and 18 is Injection control device, 19 is a laser control device,
Reference numeral 20 denotes a copper vapor laser, and by irradiating the spray injected into the high-pressure container 11 with laser light, the concentration distribution inside the spray was observed from the state of scattered light.

FIG. 6 is a diagram for explaining the spray state. The structure and phenomenon of the spray are roughly divided into four regions, and in region I, the spray goes straight at a high concentration with almost no spread, and in region II, it goes straight. Things began to meander insecurely, Region III
Then, as the meander deforms to form a branch structure, the branches change intervals, repeat division and coalescence, or gradually drop droplets from the surroundings. In Region IV, the branch structure is no longer present, and each fringe is affected by the vortex generated between it and the surrounding gas, and exhibits unique behavior and has a complicated distribution. Thus, the inside of the spray is very non-uniform, and a number of high-concentration stripes of droplets are seen, and this non-uniform high-concentration portion is, for example, a large amount when the liquid is fuel. It leads to the generation of soot.

[0005]

In the above experiment, it was found that the spray having a large turbulence in the jet when jetted from the nozzle injection hole has small high-concentration stripes and the spray also spreads widely. . In other words, the concentration distribution is almost uniform, and a large amount of ambient gas is taken in, so that the concentration becomes low.

The present invention is to solve the above-mentioned problems, and by improving the structure of the nozzle, a large turbulence is generated in the jet flow, and the liquid is mixed well with the air to obtain a uniform concentration distribution. An object of the present invention is to provide a liquid jet nozzle capable of performing the above.

[0007]

To this end, the liquid jet nozzle of the present invention has a bag portion 2 formed at the tip of a nozzle body 1.
And the nozzle body 1 so that the bag portion 2 opens to the outside.
In the liquid injection nozzle including the injection hole 3 formed in the above, the injection hole 3 includes a plurality of branch holes 3a and a plurality of branch holes 3a.
It is characterized by having one merging hole 3b that merges with each other. It should be noted that the numbers added to the above configurations are for comparison with the drawings for easy understanding, and the configurations of the present invention are not limited thereby.

[0008]

In the present invention, for example, as shown in FIG. 1C, the flow of a plurality of branch holes 3a is merged into one merge hole 3b, and a large turbulence is generated in the jet flow by utilizing the flow collision at this merge portion. Is generated and is held therein, and is rectified in the confluence hole 3b to generate a jet having large turbulence inside the confluence hole 3b.
Is sprayed in the axial direction, and the sprayed spray mixes well with air to obtain a uniform concentration distribution.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows one embodiment of a liquid jet nozzle of the present invention, FIG. A is a vertical sectional view, FIG. B is a plan view seen from the direction B of FIG. A, and FIG. C is an enlarged sectional view of FIG.

In FIG. 1, the liquid jet nozzle comprises a bag portion 2 formed at the tip of the nozzle body 1 and a nozzle hole 3 formed in the nozzle body 1 so as to open to the outside from the bag portion 2. By the sliding of the needle valve 4, the pressurized liquid is ejected from the injection hole 3 through the liquid supply path 5 and the bag portion 2.
Although the number of the injection holes 3 is six in the figure, the number is not limited to this and may be one or more.

As shown in FIG. C, the injection hole 3 is formed so that a plurality of branch holes 3a are formed on the bag portion 2 side and the plurality of branch holes 3a are merged into one merge hole 3b. The diameter and length of the branch hole 3a and the confluence hole 3b are arbitrary.

In the present invention, the liquid is provided with a plurality of branch holes 3.
A is merged into one merge hole 3b, a large turbulence is generated in the jet flow by utilizing the collision of the flows in this merged portion, and while maintaining this, it is rectified in the merge hole 3b to generate a large turbulence inside. The held jet flow is jetted in the axial direction of the confluence hole 3b, and the sprayed jet can be mixed well with air to obtain a uniform concentration distribution.

FIG. 2 shows a method of manufacturing the branch hole 3a and the confluence hole 3b. In the method of FIG. A, after cutting the branch hole 3a so as to penetrate the nozzle body 1, the confluence hole 3b is cut to the confluence portion. In the method shown in FIG. B, a branch hole 3a is provided on the nozzle body 1 side, and a merging member 7 having a merging hole 3b is attached to the nozzle body 1. It is a method of screwing. In addition to the above production example,
It may be manufactured by casting.

FIG. 3 shows an arrangement example of the branch holes 3a, FIG. A shows an example in which two branch holes 3a are provided, and FIG. B shows an example in which three branch holes 3a are provided. You may increase the number. FIG. C shows an example in which the axis of the branch hole 3a and the axis of the confluence hole 3b are not on the same plane, but are displaced so that a swirl flow is generated at the confluence portion and further large turbulence is generated.

[0015]

As is apparent from the above description, according to the present invention, the bag portion formed at the tip of the nozzle body and the injection hole formed in the nozzle body so as to open to the outside from the bag portion. In a liquid jet nozzle comprising: a plurality of branch holes, the jet hole is joined to the plurality of branch holes.
Since it has two merging holes, it is possible to generate a large turbulence in the jet flow and to mix the liquid well with the air, and to obtain a uniform concentration distribution, while maintaining the same outer shape of the nozzle as the conventional one.

[Brief description of drawings]

FIG. 1 shows an embodiment of a liquid jet nozzle of the present invention, FIG. A is a vertical sectional view, FIG. B is a plan view seen from the direction B of FIG.
FIG. C is an enlarged sectional view of FIG.

FIG. 2 is a cross-sectional view showing a method of manufacturing a branch hole and a confluence hole in FIG.

FIG. 3 is a plan view showing an arrangement example of branch holes.

FIG. 4 is a sectional view showing an example of a conventional liquid jet nozzle.

FIG. 5 is a schematic configuration diagram of an experimental apparatus according to the present invention.

FIG. 6 is a view showing a spray state for explaining the problems of the present invention.

[Explanation of symbols]

1 ... Nozzle body, 2 ... Bag part, 3 ... Injection hole, 3a ... Branch hole,
3b ... Confluence hole 4 ... Needle valve, 5 ... Liquid supply path, 6 ... Filler, 7 ...
Merging member

Claims (1)

[Claims] 1. A liquid ejecting nozzle comprising a bag portion formed at a tip of a nozzle body and a nozzle hole formed in the nozzle body so as to open to the outside from the bag portion, wherein the nozzle hole comprises a plurality of nozzle holes. And a single merging hole that joins the plurality of branch holes.