JPS6340589B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a spray nozzle, and particularly relates to a spray nozzle that performs wide-angle uniform fan-shaped spray using a gas-liquid mixing method and is used to cool high-temperature objects such as iron with mist. .

Generally, a single-fluid nozzle that uses only liquid is used to cool high-temperature objects such as iron during the manufacturing process, but with the development of continuous casting, single-fluid nozzles can cause problems such as localized supercooling. Surface cracks have occurred. In order to prevent this and shorten production time, a two-fluid nozzle is used instead of a one-fluid nozzle to spray a mixture of air and water mist over a wide area over a wide area with an even spray amount and droplet size. need to be dispersed.

Prior Art Conventionally, two-fluid nozzles provided for the above-mentioned purposes have not been satisfactory in terms of uniformity of flow rate distribution, size of droplets, spread of mist in the width direction, etc. On the other hand, when using a conventional wide-angle uniform fan-shaped nozzle as shown in Fig. 1, the uniformity of the flow rate distribution is unstable, and the spread of the mist in the width direction cannot be increased too much, resulting in a large droplet size. The problem was that the color was uneven. That is, in this nozzle, the tip 2a of the flow path 2 bored along the axis of the nozzle body 1 is formed into a round, inertial circle, or pseudo-inertial circle shape, and V-cuts 4 are made from both sides into the hole with the rounded tip. A discharge port 3 is formed by the discharge port 3. When a gas/water mixture is supplied to the flow path 2 of a nozzle with such a shape, since liquid is incompressible while gas is compressible, gas a flows through the flow path toward the small diameter part at the tip. is pushed to both sides of the flow path, and the liquid w concentrates in the center of the channel. Therefore, the mist ejected from the discharge port 3 generates fine droplets with a mixture of air and water on both sides in the spreading direction, but the center becomes almost only liquid and becomes coarse particle droplets. The width does not increase.

Purpose of the Invention This invention was made in view of the above-mentioned problems, and prevents the air/water mixture from being separated and sprayed near the discharge port, and allows uniform fine droplets to spread out in the mist. This is to ensure that it is sprayed all over the area.

Structure and operation of the invention In order to achieve the above-mentioned object, the present invention gradually reduces the tip of the inflow path for the air-water mixture provided along the axis at the center of the nozzle body to form an orifice portion. A pair of front and rear sloped surfaces are provided on both front and rear sides of the top surface of the nozzle body, and are cut out symmetrically toward the outside, and the notches in the slopes form a discharge port that is long in the front and rear direction at the tip of the orifice portion of the inflow channel. While the spraying direction is the front-back direction, stirring holes are formed symmetrically on the left and right sides perpendicular to the spraying direction of the inflow channel, and the tip of the stirring hole is gradually reduced to The side part is connected to the orifice part of the inflow channel, and the air/water mixture that has flowed into the stirring hole flows back to the orifice part of the inflow channel along the tip, stirring the mixed liquid in the inflow channel just before injection. The present invention provides a spray nozzle characterized in that separation of gas and liquid is prevented and fine droplets are dispersed from discharge holes over the entire area in the spreading direction of the mist.

EXAMPLES Hereinafter, the present invention will be explained in detail with reference to examples shown in FIG. 2 and below.

The nozzle body 10 has a substantially oval-shaped cross section, the front and rear outer surfaces 10a are linear, the left and right outer surfaces 10b are arcuate, and in the figure, the lower tip surface 10c
A sloped surface 10d is formed which is symmetrically cut into a V-shape toward the front and rear outer surfaces 10b. This cross section V
The letter-shaped inclined surface 10d is inclined upward while expanding from the center of the distal end surface 10c toward both front and rear sides, and extends upward while contracting from the distal end on the front and rear outer surface 10b.

In the center of the nozzle body 10, a steam/water mixture inflow channel 11 opened on the upper surface is vertically bored along the axis _l1 of the nozzle body 10. The inflow passage 11 has a large diameter part 11a on the upper side and a small diameter part 11b on the lower side, and is provided with an orifice part 11c whose bottom surface is rounded by gradually reducing the tip of the small diameter part 11b. The bottom of the nozzle body 1
It is located slightly inward from the tip surface 10c of 0. The tip of the orifice portion of the inflow channel 11 is connected to the above-mentioned V.
A letter-shaped notch opens from the center of the bottom surface to both front and rear sides, forming a discharge port 13 in the front-rear direction as shown in the figure, and the spray direction of the mist sprayed from the discharge port 13 is the front-rear direction.

In the nozzle main body 10, stirring holes 14 having an arcuate cross section are symmetrically formed on both left and right sides of a central small diameter portion 11b, continuous with the large diameter portion 11a of the inflow path 11. The stirring hole 14 extends along the axis to the vicinity of the lower end of the nozzle body with its inner side communicating with the small diameter inflow passage 11b, and the lower end is gradually reduced to form a round bottom surface 14a. The bottom surface 14a is located at substantially the same position as the bottom surface of the inflow channel and adjacent to it in the left and right direction, and the inner side slightly above the bottom surface 14a communicates with the left and right side surfaces of the orifice portion 11c of the inflow channel 11. In this way, the stirring holes 14 are arranged in a direction perpendicular to the spray direction of the discharge port 13.

In the spray nozzle having the above-described structure, the air/water mixture flows from the large diameter part 11a of the inflow path 11 into the small diameter part 11b in the center and the stirring holes 14 on both left and right sides, and flows through each of them along the axis. . Stirring hole 1
When the steam/water mixture that has flowed into the tube 4 reaches the bottom surface 14a, it flows through the inflow channel 1 that communicates along the round bottom surface 14a.
The water flows backward into the orifice portion 11c of No. 1 as shown in the figure. Due to the inflow liquid flowing back from the stirring hole 14, the air-water mixture flowing down the orifice portion 11c of the inflow path 11 is stirred as shown in FIG. Therefore, the liquid and gas, which were unevenly distributed in the orifice part 11c with the liquid separated in the center and the gas around, are mixed uniformly by the stirring caused by the backflow from the stirring hole, and a uniform gas is created near the discharge port 13. It becomes a water mixture. Therefore, fine droplets are generated in the air-water mixture over the entire spread of the mist ejected from the discharge port 13. At this time, since the stirring holes are provided in a direction perpendicular to the injection direction, the spreading of the mist in the width direction is not inhibited by stirring, and the mixing of gas and liquid is uniform throughout the spreading direction. Because gas and liquid do not separate in the direction of expansion,
It is easier to control the flow rate distribution evenly, and the width of the mist becomes wider.

Using the spray nozzle of the present invention shown in FIG. 2 and the conventional spray nozzle shown in FIG. 1, experiments were conducted to compare the particle size of mist and the flow rate distribution.

Particle Size Comparison Experiment The spray nozzles shown in Figures 1 and 2 were machined to have the same dimensions for the inflow channel and orifice, and the same air/water mixture was used, with an air pressure of 4 kg/cm ^{2 and a liquid pressure of 4 kg/cm 2} .
The mist below the nozzle when spraying at cm ² is as shown in Figure 3. In case A of the conventional example in Figure 1, the Sauter average particle diameter is 240μ, and in case B of the present invention in Figure 2. was 180μ. These results demonstrate that the Sauter average particle size is smaller in the fog with stirring holes, and that air is mixed into the center of the mist, contributing to its miniaturization.

Flow rate distribution comparison experiment Similar to the above particle size experiment, the orifice shape etc. were machined to the same dimensions, and the same air/water mixture was sprayed at an air pressure of 3 Kg/cm ² and a liquid pressure of 3 Kg/cm ² , and the spray height was to
At a position of 100 mm, the flow rate distribution was measured in the direction of the spread of the mist, and the thickness of the mist was also measured using the spray pattern. The results are shown in Figure 4.The conventional nozzle shown in Figure 1, shown in A, spreads to 400 mm.
The length of the uniform part S _L is 80 mm, 100 mm from directly below the nozzle.
In remote areas, it was 50%. Additionally, the thickness of the fog was narrow at 35 mm in the center. On the other hand, in the nozzle of the present invention shown in Fig. 2 shown in B, the width is 400 mm as in the conventional type, but the length S _L of the equal part is
It is extremely long at 280mm. Moreover, the thickness of the fog is 50mm at the center, which is thicker than the conventional type. From the above results, in the nozzle of the present invention, the gas and liquid are sufficiently stirred near the orifice, and the air/water mixture is injected almost evenly in the direction of mist spread, making it easier to stably obtain an even flow rate distribution. , and it has been proven that a wide fog can be obtained.

Note that the present invention is not limited to the embodiment shown in FIG. 2, and the nozzle body 1' may have a perfect circular cross section as shown in FIG. The tip 14'a has a conical shape and does not necessarily have to be rounded. Furthermore, as shown in FIG. 7, two stirring holes 14'' may be provided in the direction perpendicular to the spray direction of the inflow channel 11'. In this case, the inclined surface 10'd of a V-cut cut into the nozzle tip surface. The width of the stirring hole 14'' is not widened toward the outside, but rather narrow, so that the bottom surface of the stirring hole 14'' does not open. Furthermore, as shown in FIG. 8, the discharge port 13' may be formed in a circular shape that is long in the front-rear direction. Note that the cut is not limited to a V-cut, but may be a U-cut with a circular discharge opening as shown in FIG.

In the modified examples shown in FIGS. 5 to 9 above,
Since the other parts have the same structure as in FIG. 2, they will be given the same reference numerals and the explanation will be omitted.

Effects As is clear from the above explanation, according to the spray nozzle of the present invention, stirring holes are arranged symmetrically at positions perpendicular to the spray direction so that the air-water mixture in the orifice near the discharge port is sufficiently stirred. Since the configuration is provided with the above, separation of gas and liquid in the vicinity of the discharge port is prevented. Therefore, it has the effect of generating fine droplets in a mixed state of air and water over the entire spread of the mist, and has extremely large effects on the uniformity of the flow rate distribution, the spread of the mist, etc.

[Brief explanation of the drawing]

Figure 1 shows a conventional spray nozzle, A is a front view, B is a plan view, C is a bottom view, D is a sectional view taken along the line C, E is a sectional view taken along the line D, and Figure 2 shows the spray nozzle of the present invention. A is a front view, B is a side view, C is a plan view, D is a bottom view, E is a cross-sectional view of D, H is a cross-sectional view of D, G is an enlarged view of the main parts of D, and Figure 3 A and B are grains. Drawings showing the results of diameter experiments, Figure 4 A,
B is a drawing showing the results of a flow rate distribution experiment, FIG. 5 is a modified example of the spray nozzle of the present invention, A is a plan view, B is a sectional view, FIG. 6 is a sectional view showing another modified example, and FIG. 8 shows another modification; A is a top view; B is a bottom view; FIG. 9 is a top view; 10 is a bottom view, B is a sectional view, 10... Nozzle main body, 11... Air-water mixed liquid inflow channel, 13... Discharge port, 14... Stirring hole.

Claims (1)

[Claims] 1 The tip of the inlet channel for the air/water mixture provided along the axis at the center of the nozzle body is gradually reduced to form an orifice, and the orifice is formed symmetrically outward on both the front and rear sides of the top surface of the nozzle body. A pair of front and rear sloped surfaces are provided with a notch, and the cutout of the slope forms a discharge port that is long in the front and back direction at the tip of the orifice portion of the inflow path, and the spray direction is the front and rear direction. Stirring holes are formed symmetrically on both left and right sides perpendicular to the spray direction, and the tip of the stirring hole is gradually reduced, and the side part inward from the tip is connected to the orifice of the inflow path, and the flow flows into the stirring hole. A spray nozzle characterized in that the steam/water mixture flows back into the orifice part of the inflow path along the tip and stirs the mixture in the inflow path immediately before being sprayed.