JPS5913502Y2 - Rotary atomization device - Google Patents

Description

[Detailed description of the invention] This invention utilizes the centrifugal force caused by the rotation of the rotating shaft to atomize liquid, such as liquid fuel, from the injection port provided on the wall of the cylindrical rotating shaft in the circumferential direction of the rotating shaft. It concerns a device that sprays with uniform distribution.

The conventional method of supplying liquid such as fuel from the front end of the rotating shaft through a small diameter liquid passage provided in the center and atomizing the liquid using the centrifugal force of the rotating shaft is as shown in Fig. 5. In some cases, only one row of injection ports 302 are provided in the internal hole 303 of the rotating shaft 301 that communicates with a liquid passage (not shown), or in a sixth
As shown in the figure, there is one in which a rotating shaft 401 is provided with a spiral nozzle 402 that communicates with a liquid passage 403.

However, it is known that in the apparatus shown in FIG. 5, the particle size of the spray injected from the injection port 302 does not become very small.

This is also clear from FIG. 7, which shows the relationship between the circumferential speed of the rotating shaft (m/sec) and the particle size μm, as will be described later.

It is known that the particle size becomes considerably large, especially when the rotational speed of the rotating shaft 301 is low and the circumferential speed is not high.

On the other hand, it is known that by providing a spiral nozzle 402 as shown in FIG. 6, a spray having a small particle size can be obtained even when the circumferential speed of the rotating shaft 401 is small.

However, when the spiral nozzle 402 is provided on the rotating shaft 401,
Since a very large centrifugal force acts on the spiral nozzle 402 due to the rotation of the rotating shaft 401, there is a risk that the spiral nozzle 402 will jump out from the rotating shaft 401 unless the spiral nozzle 402 is firmly attached to the rotating shaft 401.

In addition, the device shown in Fig. 6 has many components, and the spiral nozzle 4
02 requires high machining accuracy.

One purpose of this invention is to transform the liquid introduced into the small diameter liquid passage provided at the center of one rotating shaft into extremely small particle size particles.
Moreover, it is an object of the present invention to provide a rotary atomization device that generates spray that is evenly distributed in the circumferential direction of a rotating shaft.

Another purpose of this invention is that it can be installed facing high-temperature areas such as the combustion chamber of a gas turbine, and the rotary atomization system supplies spray with extremely small particle size and uniform distribution to the combustion chamber. The purpose is to provide equipment.

This invention will be described below based on drawings showing embodiments, and an example of the application of this invention to a gas turbine will also be described.

FIGS. 2, 3, and 4 show an embodiment of this invention. A rotary atomizer 100 has one rotating shaft, for example, the rotating shaft 1 of a gas turbine T, which will be described later, and a small diameter Liquid passage 2, conical surface 3a and cylindrical surface 3 concentric therewith
b, and consists of an internal hole 3 whose rear end is closed by a partition wall 21, and two rows of injection ports 101 and 102 arranged at an interval of 1 on the cylindrical surface 3b.

The liquid passage 2 communicates with the front end of the internal hole 3 at its rear end, and the diameter of the conical surface 3a increases toward the rear.

The cylindrical surface 3b has the same diameter as the rear end of the conical surface 3a and is connected to the rear end thereof.

The injection ports 101 are located in front of the injection ports 102, and as shown in FIG. 3, four injection ports are arranged at equal intervals in the circumferential direction of the cylindrical surface 3b, and the injection ports 102 are arranged at equal intervals as shown in FIG. Two are placed in the.

The diameter of the injection port 101 is 0.5 to Q, 3 mm, but the diameter of the injection port 102 is sufficiently larger than the diameter of the injection port 101.

In the above configuration, liquid supplied from the front end (left end not shown in FIG. 2) of the rotating shaft 1 is supplied to the internal hole 3 via the liquid passage 2.

The liquid supplied to the internal hole 3 is subjected to centrifugal force due to the rotation of the rotating shaft 1, and flows backwards along the conical surface 3a of the internal hole 3 in the form of a thin film, reaching the cylindrical surface 3b, where it spreads over its entire circumference. It spreads in a thin film.

As the rotational speed of the rotating shaft 1 increases and the circumferential speed of the inner cylindrical surface 3b increases, the centrifugal force acting on the liquid becomes extremely large (for example, if the rotating shaft 1 is the rotating shaft of a gas turbine, the cylindrical surface 3b
The circumferential speed is approximately 200 m/sec.

At this circumferential speed, the centrifugal force acting on the liquid is on the order of 105G.

However, G is gravitational acceleration.

) The liquid spreads in a very thin film over the entire circumference of the cylindrical surface 3b.

This film-like liquid flows through the injection port 101 provided on the cylindrical surface 3b,
102 in the radial direction in equal amounts and with a large centrifugal force.

In this case, the fuel flow rate is determined by the injection ports 101 and 10 when the rotating shaft 1 is rotating at the same high speed as the rotating shaft of the gas turbine.
The flow rate is much lower than the flow rate assuming that all the liquid is packed in the cross section of 2.

The reason for this is that liquid is injected from each of the injection ports 101 and 102 in small but equal amounts.

Since the liquid is injected at high speed under the influence of a very large centrifugal force as described above, the liquid is subjected to a large shearing action by the surrounding gas and is turned into a spray having extremely small particle sizes.

Generally, in a rotary atomization device, the energy that contributes to atomization of a liquid is the energy of movement due to centrifugal force acting on the liquid.

Utilizing this energy most effectively results in spray having small particle size.

The most efficient way to utilize the energy imparted to a liquid is to make the surface area/weight ratio of the liquid as large as possible before the liquid begins to break up into droplets.

Therefore, as in the rotary atomization device 100 of this invention, the liquid is spread as an extremely thin liquid film on the cylindrical surface 3b of the internal hole 3,
Furthermore, an atomization device that injects a small amount at a time with an extremely large centrifugal force from two rows of injection ports 101 and 102 can obtain a spray with an extremely small particle size.

FIG. 7 shows the rotary atomizer 100 according to this invention, with the horizontal axis representing the circumferential speed of the rotating shaft in m/sec and the vertical axis representing the particle size μm.
A comparison is shown between the characteristics of the conventional rotary atomizer shown in FIG. 5, which has only one row of injection ports having a diameter of 0.2 to 2 mnn (region A in the figure).

Water is used as the liquid, and the particle size is shown in 5 outer average diameter (body area average diameter).

When fuel oil is used as the liquid, the particle size is 6
It becomes 0-70%.

It can be seen from FIG. 7 that the particle size obtained from the apparatus shown in FIG. 5 with only one row of injection ports is much larger than the particle size obtained by the rotary atomizer 100 of this invention, no matter how small the injection port is. Ru.

The reason for this is that the rotary atomizer 100 is located at a distance of l (l is 2 m).
This is because there are two rows of injection ports 101 and 102 separated by a distance of about m).

In this case, it is desirable that the diameter of the injection ports 102 is sufficiently larger than the diameter of the injection ports 101 and that the number of injection ports 102 is not greater than the number of injection ports 101.

The reason for this is that a part of the liquid evaporates due to heat transfer from the conical surface 3a or cylindrical surface 3b of the internal hole 3 of the rotating shaft 1, and the injection port 1
When a mixture of liquid and its vapor is injected from 01 and 102, even if the injection amount from the small-diameter injection port 101 is not sufficient due to steam blockage, if the diameter of the injection port 102 is sufficiently large, both liquid and vapor will be injected. This is because it is injected within the mouth 102 with almost no resistance.

□If the diameters of the injection ports 101 and 102 are both normal values, the flow of the liquid injected will vibrate or pulsate, or the flow rate of the injection port 101 and 102 will be limited to a small value. A problem occurs.

Next, the operation of the rotary atomizer 100 when it is installed in the gas turbine T shown in FIG. 1 and the rotating shaft 1 is used as the rotating shaft of the gas turbine T will be explained together with the structure and operation of the gas turbine T.

The rotating shaft 1 is rotated by a turbine rotor 17, which will be described later.

The rotation of the rotating shaft 1 rotates the compressor rotor 4, and air is sucked into the compressor rotor 4 as shown by arrow A.
The air is imparted with velocity energy and flows into the tiff user blade 6a of the tiff user 6 as shown by arrow B, and is decelerated and pressurized by the tiff user 6, creating an annular air flow between the outer housing 7 and the inner housing 8 as shown by arrow C. Sent to Route 9.

Air flows from the air passage 9 as shown by the arrow, is introduced into a heat exchanger (not shown), is heated and introduced into the air chamber 10 as shown by the arrow E, and also passes through the ventilation pipe 12 as shown by the arrow F. It is also introduced into the air chamber 11 in the same way.

On the other hand, liquid fuel introduced into the liquid passage 2 from the front end (left end not shown in FIG. 1) in the interrotary shaft 1 passes through the passage 2 and enters the internal hole 3, and due to centrifugal force, the liquid fuel enters the conical surface 3a, A very thin liquid film forms on the cylindrical surface 3b and the injection ports 101, 10
2 into the combustion chamber 15, and air holes 19 provided in the casings 13a, 14a of the gas turbine 7.
The particles are sheared by the air introduced into the combustion chamber 15 from a, 19b, 19c, 19d, and 19e, and become a spray with extremely small particle size and uniform distribution in the circumferential direction of the rotating shaft 1.

The atomized fuel is ignited by the spark plug 20 and then flows into the combustion chamber 15.
Continuous combustion inside.

The combustion gas is mixed with air introduced into the combustion chamber 15 through air holes 19f and 19g provided in the casings 13b and 14b, lowered to an appropriate temperature, and introduced into the turbine nozzle 16 as shown by arrow G. , is blown onto the turbine rotor 17 to rotate it.

Note that 18 is a gas bearing device that supports the rotary shaft 1 so as to be rotatable at high speed with another bearing (not shown).

This device has a small diameter liquid passage concentric with the rotating shaft, an internal hole consisting of a conical surface and a cylindrical surface connected to the rear end of the conical surface, and the conical surface has a small diameter. The front end of the cylindrical surface is connected to the rear end of the liquid passage, the rear end of the cylindrical surface is closed, and two rows of injection ports (front and rear) penetrating the wall of the rotary shaft are installed in the part of the rotary shaft corresponding to the cylindrical surface in the circle of the rotary shaft. They are arranged at equal intervals in the circumferential direction, the aperture of the rear row nozzles is set larger than the aperture of the front row nozzles, and the number of nozzles in the front row is set to be greater than the number of nozzles in the double row, so the following is done. It has excellent effects.

(b) When the rotating shaft is rotating at high speed, the liquid supplied from the front end of the liquid passage forms an extremely thin liquid film on the conical surface and cylindrical surface of the internal hole, and then flows from the injection port at high speed in the radial direction of the rotating shaft. It is injected by the surrounding air and is strongly sheared by the surrounding air, resulting in a spray with extremely small particle size and uniform distribution in the circumferential direction of the rotating shaft.

(b) Therefore, when used as a fuel supply device for a gas turbine, spray with small particle size and uniform flow rate distribution in the circumferential direction can be obtained in the combustion chamber of the gas turbine, improving fuel evaporation and mixing performance with air. As a result, the combustion efficiency, uniformity of temperature distribution, and heat load factor of the gas turbine are significantly improved.

(c) Also, when used as a fuel supply device for a gas turbine, the temperature of the rotating shaft increases due to heat conduction from the turbine rotor, etc., and a portion of the fuel evaporates due to heat transfer from the conical and cylindrical surfaces of the internal hole. Even in such a case, the injection port 101
Since the size of the injection port 102 located at the rear of the combustion chamber can be made sufficiently large, problems such as pulsation and vibration do not occur in the flow rate of fuel injected into the combustion chamber.

[Brief explanation of the drawing]

Fig. 1 is a partial vertical sectional view of a gas turbine in which an embodiment of this invention is used in a gas turbine, Fig. 2 is a longitudinal sectional side view of the first embodiment of this invention, and Fig. 3 is the same as that shown in Fig. 2. III
-III line sectional view, Figure 4 is the I■-IV line sectional view of Figure 2, Figures 5 and 6 are vertical side views of the conventional rotary atomizer, and Figure 7 is the conventional rotary atomizer. It is a characteristic comparison diagram of a rotary atomization device. 1...Rotating shaft, 2...Liquid passage, 3.
...inner hole, 3a...conical surface, 3b...
...Cylindrical surface, 101, 102...Injection port.

Claims (1)

[Scope of utility model registration request] One rotary shaft has an internal hole consisting of a small-diameter liquid passage concentric therewith, a conical surface, and a cylindrical surface connected to the large-diameter rear end of the conical surface. The small-diameter front end communicates with the rear end of the liquid passage, the rear end of the cylindrical surface is closed, and the part of the rotating shaft corresponding to the cylindrical surface penetrates the wall of the rotating shaft in two rows in the circumferential direction. It has injection ports arranged at equal intervals, the diameter of the injection ports in the rear row is set larger than the diameter of the injection ports in the front row, and the number of injection ports in the front row is set to be greater than the number of injection ports in the rear row. A rotary atomization device featuring: