JPH07116561A - Jetting nozzle - Google Patents

Abstract

PURPOSE:To jet an air current at high pressure several times as large as the supply pressure by forming a high pressure jetting port which is opened to surround a primary side nozzle at the inlet of a secondary side nozzle and through which a secondary fluid is jetted towards the center of a primary fluid from the primary side nozzle at higher pressure than that of the primary fluid. CONSTITUTION:In an injection port 4 of a secondary side nozzle 2, a high pressure jetting port 8 is annularly opened over an opening area (a) so as to surround an outlet 3 of a primary side nozzle 1. The high pressure jetting port 8 is connected to a compressed gas feeding pass 10 through a needle valve 9. A secondary fluid having higher pressure tan saturated steam is fed from the compressed gas feeding pass 10. The secondary fluid is jetted at prescribed angles so that it may converge to the center of the primary fluid jetted from the primary side nozzle 1. When the primary fluid jetted from the primary side nozzle 1 and the secondary fluid jetted from the high pressure jetting port 8 are mixed in a mixing chamber 5 of the secondary side nozzle 2, the formed shock waves are jetted from an outlet 7 through a throat part 6 at a flow velocity, the same as the order of sonic velocity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection nozzle, and more particularly to an injection nozzle which obtains a high pressure output from a low pressure input.

[0002]

2. Description of the Related Art Ships often use high pressure steam pressure such as turbine drive, and equipment using various kinds of steam pressure is used. For example, in a boiler, a soot blower that removes soot adhering to the water tube group, which is the main heat transfer surface, by blowing high-pressure steam is provided to enhance the heat transfer effect of the boiler.

Similarly, a chemical tank laid in a chemical factory,
Also when cleaning water stains, soot, residues, etc. in oil tanks,
A method of blowing steam or compressed air from a nozzle to blow off scales, soot, residues and the like may be adopted.

Many of these conventional turbines or sootblowers use pipe-shaped nozzles in which a large number of small holes are formed on the peripheral surface at appropriate intervals in the circumferential direction and the axial direction. Depending on the pipe, a nozzle such as a straight nozzle or a divergent nozzle that directly penetrates the pipe through a small hole that ejects an airflow is planted on the peripheral surface of the pipe at appropriate intervals in the circumferential direction and the axial direction. There is one in which a fluid is ejected through a nozzle.

Further, although a pressure vessel is used to temporarily store the pressure steam from the boiler, the conventional pressure vessel has a structure in which the pressure from the boiler is directly led to the pressure vessel.

[0006]

However, in these nozzles, since the cross-sectional area of the flow passage on the output side is reduced from the pressure source side to increase the jet pressure, compared with the supply pressure of the supplied steam or compressed air. Although it is possible to slightly increase the jet pressure, it is not possible to obtain a high-pressure jet stream that is several times higher, and when the pressure on the primary side is not sufficiently high, the pressure on the secondary side is also expected. It has the drawback of not being as expensive.

Therefore, when the conventional nozzle is used in a soot blower, it may not be possible to blow out the soot sufficiently by spraying for a short time, and the same problem may occur when cleaning a chemical tank or an oil tank. There is.

Further, even in the injection nozzle for blowing the pressure fluid to the turbine, the fluid cannot be ejected at a pressure higher than the fluid pressure supplied to the nozzle. Furthermore, even in a pressure vessel, it is not possible to accumulate steam at a pressure higher than the pressure output by the boiler by only directly guiding the steam from the boiler as described above.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an ejection nozzle capable of ejecting an air flow at a high pressure several times higher than the supply pressure.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a primary side nozzle for injecting a primary fluid at a high speed and an outlet of the primary side nozzle. A secondary side nozzle having a larger diameter than that of the primary side nozzle, which has a narrower flow passage cross-sectional area, and an inlet port of the secondary side nozzle, which is opened around the primary side nozzle and which is the secondary fluid from the primary side nozzle. And a high-pressure jet port that jets out toward the center at a pressure higher than that of the primary fluid.

Saturated steam is used as the primary fluid,
Also, room temperature air can be used as the secondary fluid. Further, the throat of the secondary side nozzle is provided with a spiral groove or ridge that gives a swirling component to the fluid passing through the throat. Further, if the throat diameter of the secondary nozzle and the outlet diameter of the primary nozzle are formed to be equal, the object of the present invention can be achieved more effectively.

[0012]

[Operation] In the above configuration, in the secondary side nozzle, the primary fluid ejected from the primary side nozzle at high speed and the secondary fluid ejected from the high pressure outlet are mixed in the secondary side nozzle to generate a shock wave. Is generated, and this shock wave is ejected from the secondary side nozzle at a speed of about the speed of sound, so that a shock wave whose pressure is several times higher than the supply pressure of the primary fluid and the secondary fluid higher than this is generated from the secondary side nozzle. Gush out.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An injection nozzle according to an embodiment of the present invention will be specifically described below with reference to the sectional view of FIG.

This injection nozzle has a two-stage nozzle structure in which a primary side nozzle 1 and a secondary side nozzle 2 are continuous. The cross-sectional area of the flow path of the primary side nozzle 1 is gradually narrowed, and the inner peripheral surface of the outlet 3 is formed in a right cylindrical shape. A primary fluid having a lower pressure than the secondary fluid described below is supplied to the primary nozzle 1,
The diameter (outlet diameter) d1 of the outlet 3 is designed so that the saturated vapor is jetted into the secondary side nozzle 1 at a flow velocity of about sonic velocity or transonic velocity.

Further, the secondary nozzle 2 is formed with a diameter larger than the outlet diameter of the primary nozzle 1, and the inlet 4 and the mixing in which the cross-sectional area of the flow path is gradually reduced continuously to the inlet 4. Room 5
And further, the same diameter d2 as the outlet diameter d1 of the primary side nozzle 1.
The throat portion 6 and the outlet 7 formed in a divergent shape are connected to each other.

At the entrance 4 of the secondary nozzle 2, a high-pressure jet 8 is formed in an annular shape over an opening area a so as to surround the outlet 3 of the primary nozzle 1. The high-pressure jet port 8 is connected to a compressed air supply passage 10 with a needle valve 9 interposed, and a secondary fluid having a higher pressure than the saturated vapor is supplied from the compressed air supply passage 10. The primary fluid ejected from the primary side nozzle 1 is designed to be ejected at a predetermined angle so as to converge on the center of the primary fluid.

When the primary fluid ejected from the primary nozzle 1 and the secondary fluid ejected from the high-pressure ejection port 8 are mixed in the mixing chamber 5 of the secondary nozzle 2, a shock wave is formed,
This shock wave is ejected from the outlet 7 to the outside through the throat portion 6 at a velocity of sound speed.

If necessary, the inner peripheral surface of the throat portion 6 is provided with a spiral concave or convex ridge that imparts a swirling component to the fluid passing through the throat portion 6. Therefore, the airflow that has passed through the throat portion 6 is given a swirl component to enhance the convergence, and is jetted out from the outlet 6 as a high-pressure shock wave without dispersing the jetting energy.

In the above structure, the primary fluid is 3 kg / c
When the saturated steam of m ² The use of ambient temperature air 5 kg / cm ² as a secondary fluid, the output of 10-15 kg / cm ² was obtained. That is, an air flow having a strong propulsive force is ejected at a high pressure which is 3 to 5 times higher than the supply pressure of the primary fluid and 2 to 3 times higher than the supply pressure of the secondary fluid. Further, since the flow velocity is high, a large amount of jetted fluid can be obtained.

Therefore, when this injection nozzle is used to drive the turbine, the output of the turbine can be increased to several times that of the conventional one, and the soot blowing of the boiler, the soot blowing of the economizer, the pressure vessel, the chemical tank or When it is used for cleaning an oil tank or the like, a jet fluid having a pressure several times higher than that of a conventional one can be obtained, so that soot and residues can be sufficiently blown off in a short time.

The generation of the shock wave becomes unstable when the flow rate of the secondary fluid becomes excessive. However, by adjusting the opening of the needle valve 9, the shock wave can be generated stably and continuously. . Further, if the area of the ejection port 4 of the secondary nozzle 2 and the outlet area of the primary nozzle are substantially equal to each other, or if the area of the ejection port 4 of the secondary nozzle 2 is designed to be slightly larger, a greater effect can be obtained.

In the injection nozzle according to another embodiment of the present invention shown in the sectional view of FIG. 2, a compressed air supply passage 10 is formed around the primary side nozzle 1 and the high pressure ejection port 8 is provided in the primary side nozzle 1. It is composed of 6 to 8 holes that are equally spaced in the circumferential direction around the outlet. The needle valve 9 is provided outside the drawing. Further, the entrance 4 of the secondary side nozzle 2 and the mixing chamber 5 are formed in a series of truncated cones.

In FIG. 2, reference numeral 11 is a nut for connecting the end of the compressed air supply passage 10, and 12 is a screwing portion for connecting the end of the steam supply passage (not shown).

The other construction, operation and effect are similar to those of the above-mentioned embodiment, and therefore detailed description thereof will be omitted to avoid duplication. FIG. 3 shows a soot blower using an injection nozzle according to another embodiment of the present invention.
Is closed by end plates 23 and 24 at both ends of the inner and outer double pipes 21 and 22, respectively, and a primary steam chamber 25 is provided inside the inner pipe 21 and a secondary side steam chamber 25 is provided between the inner and outer pipes 21 and 22. The primary side nozzles 1 of a plurality (here, five) of injection nozzles are formed on the inner wall of the inner pipe 21 and the secondary side nozzles 2 are supported on the outer wall of the outer pipe 22, respectively. There is. An air passage 27 that connects the secondary air chamber 26 and the high-pressure jet port 8 is formed in the meat wall portion of the secondary nozzle 2.

The other constitution, action and effect of the injection nozzle according to this embodiment are the same as those of the above-mentioned respective embodiments, and in the soot blower using this injection nozzle, the pressure from each injection nozzle is several times that of the conventional one. A mixed gas of propulsive steam and compressed air is ejected. Therefore, it becomes possible to sufficiently blow out the soot by spraying for a short time.

[0026]

As described above, in the injection nozzle of the present invention, the nozzle has a two-stage structure and the primary fluid ejected at a high speed is mixed with the secondary fluid having a higher pressure than this at a higher speed. It is possible to generate a shock wave and jet the airflow with a pressure or a propulsive force that is several times the supply pressure.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a sectional view of another embodiment of the present invention.

FIG. 3 is a partially cutaway side view of a sootblower according to another embodiment of the present invention.

[Explanation of symbols]

 1 Primary Nozzle 2 Secondary Nozzle 3 Outlet 4 Entrance 5 Mixing Chamber 6 Throat 7 Outlet 8 High Pressure Jet

Claims (4)

[Claims] 1. A primary side nozzle for injecting a primary fluid at a high speed and an inlet of the primary side nozzle, which is continuous with the outlet of the primary side nozzle, has a diameter larger than the outlet diameter of the primary side nozzle, and the flow passage cross-sectional area is gradually narrowed. A secondary nozzle and a high-pressure jet that is opened around the primary nozzle at the inlet of the secondary nozzle and ejects a secondary fluid from the primary nozzle toward the center of the primary fluid at a pressure higher than that of the primary fluid. An injection nozzle having an outlet. 2. The injection nozzle according to claim 1, wherein the primary fluid is saturated steam and the secondary fluid is room temperature air. 3. The injection nozzle according to claim 1, wherein the throat portion of the secondary side nozzle is provided with a spiral groove or protrusion that gives a swirling component to the fluid passing through the throat portion. . 4. The injection nozzle according to claim 1, wherein a throat diameter of the secondary side nozzle is formed to be equal to an outlet diameter of the primary side nozzle.