JPS6027906B2 - Louver device for air intake of nuclear equipment building - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a louver device installed at an air conditioning air intake in a building of a nuclear power generation facility to prevent rainwater from entering.

Generally, a reactor building, a turbine building, etc. of a nuclear power plant is provided with a ventilation air conditioning system, and the air intake port thereof is opened on the side of the building.

A louver device was installed at this air intake to prevent rainwater from entering. This louver device generally had a louver blade A with a cross-sectional shape as shown in Figure 1, but in the conventional type, a large amount of rainwater entered, and as a result, air conditioning equipment was subject to significant corrosion. . In particular, since nuclear power plants are generally located on the coast, rainwater contains salt, which further increases corrosion. When we investigated the ingress route of this rainwater, we found that the first route is that when a raindrop B hits the louver blade A, droplets C the size of a pongee are generated, which infiltrates along with the air flow. there were. In addition, the second path was one in which rainwater droplets D accumulated on the lower edges of the louver blades A entered by air flow when they fell. In order to prevent such rainwater from entering, the angle of the louver blade A with respect to the horizontal direction may be increased, or
You can increase the width of the louver blade A...
In this case, the pressure loss of the louver device increases, and in order to obtain the necessary air flow rate, the closed area of the air intake must be increased. However, in nuclear equipment buildings, the area of the entrance must be made as small as possible because of the need to shield radiation and prevent the spread of radioactive materials. For this reason, it has been desired to develop a louver device that allows a small amount of rainwater to enter and has a small pressure loss. The present invention has been made based on the above circumstances, and its purpose is to provide a louver device with a small amount of rainwater intrusion and with a small pressure loss during air circulation. The present invention will be explained below according to an embodiment shown in FIGS. 2 to 6.

1 in the figure is the turbine building of a nuclear power plant, with ventilation,
An air intake port 2 for an air conditioning system is formed. The air intake port 2 is open on the side surface of the turbine building 1.
A louver device 3 is attached to this air intake port 2. 4... is the louver board, and Mr. 5...
.

The lower crosspiece 6 and the left and right vertical crosspieces 7 constitute a rectangular frame, and a large number of louver blades 8 are attached to this frame in the horizontal direction. A plurality of these louver plates 8 are arranged as necessary to cover the air intake port 2. Further, a filter 9 is provided within the air intake port 2, and is configured to remove mist and dust that cannot be removed by the louver device 3. The louver plate 4 is constructed as follows. That is, bolt fitting grooves 10, 10 are formed in the upper crosspiece 5 and lower crosspiece 6, and these bolt connecting grooves 10, 1W allow the heads of the mounting bolts 11 to move freely but not to rotate. It is iron-coated. These mounting bolts 11 pass through mounting plates 12, 12 protruding from the turbine building 1 side and are tightened with nuts 13 to fix the louver plate 4. A lattice-shaped bird screen 14 is attached to the outside of the louver plate 4 to prevent birds from entering. A large number of louver blades 8 . . . are laterally attached to the frame body made up of the upper rail 5, the lower rail 6, and the vertical rails 7, 7. These louver blades 8... are tilted so that the outer green side is located downward. The outer green part, that is, the lower twill part of these louver blades 8... is curved so as to be convex upward, and the mirror slope of the lower edge of these louver blades 8 becomes larger as it goes downward. It is configured as follows. Water receiving grooves 15 with open upper surfaces are formed in the underlines of these louver blades 8. Further, the upper green portions of these louver blades 8 are bent in the vertical direction, and the upper twill portions of the brackets are formed with water cutting ridges 16 that protrude in the horizontal direction. And the vertical bar 7,
A drain groove 17 is formed in 7 and is continuous in the vertical direction. Both end portions of the water receiving grooves 15 of the louver blades 8 protrude to the sides of the louver blades 8. It matches.
Furthermore, flow guide pieces 18 are provided to protrude downward from the bottom surfaces of both end portions of these water receiving grooves 15 .
Further, the upper surface of the lower crosspiece 6 is formed to be smooth and beveled so that the outer side faces downward. Further, a closing portion 19 is provided upwardly projecting from the inner edge of the lower beam 6, and this closing portion 19 closes off the space between the lower branch 6 and the lowest louver blade 8. Further, a water receiving plate 20 is protruded downward from the outer green part of the upper crosspiece 5, and the lower edge of this water receiving plate 20 has a water receiving groove similar to the louver blades 8. 15 is formed. Next, the operation of the above embodiment will be explained. When it rains and there is wind, the raindrops B fall diagonally as shown in FIG. 6 and hit the lower green parts of the louver blades 8, producing small-diameter droplets C. by the way,
Since the lower edges of these louver blades 8 are curved to be convex upward, the slope of the lower green portion becomes larger as it goes upward. Therefore, the raindrop B hitting this lower edge comes to hit from a direction above the normal line of the hitting part. Therefore, droplets C... are scattered outward,
Therefore, the amount of intrusion of these droplets C... is significantly reduced. In addition, rain that hits the upper surface of these louver blades 8 flows down the upper surface, is collected in the water receiving groove 15, and is collected in the vertical beam 7,
Water is drained from the drainage ditch 17 of 7. Therefore, water droplets do not drip from the lower green of these louver blades 8, and water droplets on the louver blades do not enter the air intake port 2 due to the air flow. In reality, rainwater that hits the outer surface of the water receiving groove 15 may drip from the lower surface of the water receiving groove 15, so the lower the depth of the water receiving groove 15, the better. If the depth is too low, rainwater may overflow from the water receiving groove 15 if there is a large amount of rainfall, so it is preferable that the depth is about 5 skins. In addition, during strong winds or when the velocity of air flowing between the louver blades 8 is high, water droplets E attached to the upper surface of the louver blades 8 may move upward due to the air flow. , water droplets E are formed on the upper edges of these louver blades 8, so water droplets E are absorbed by these water cutters 16...
It stops at the part , and does not enter the air intake port 2.
In addition, in the past, water droplets that had accumulated on the upper surface of the lower branch would be pushed by the air flow and scatter from the protrusion on the upper surface of this lower branch, and enter the lower branch. Since the space between the louver blade 8 and the louver blade 8 is closed, water does not enter as described above. In addition, rainwater flowing through the turbine building 1 and the top 5 is collected at the water receiving plate 15 of the water receiving plate 20, so water droplets do not drip from the top 5, and such water droplets are prevented by air flow. There will be no intrusion. In addition, both ends of the water receiving grooves 15 protrude laterally and are fitted with iron into the drain grooves 17 of the vertical beams 7, so that rainwater is reliably drained from the drain grooves 17.
You will be guided within 7 days. Further, since flow guide pieces 18 are protruded from the bottoms of both ends of these water receiving grooves 15..., rainwater flows down through these flow guide pieces 18... There is no chance of it getting around to the bottom surface of the container and dripping. Next, the results of experiments conducted to confirm the effects of the present invention will be shown.

Figure 7 shows the infiltration rate of rainwater for a conventional louver device with louver blades as shown in Figure 1.
It can be seen that the shallower the angle of the louver blade with respect to the horizontal direction, the greater the rate of rainwater intrusion, reaching 7 to 8% in 300. Next, FIG. 8 shows the results regarding the relationship between the angle of the louver blades and the closure ratio of a louver device having louver blades according to an embodiment of the present invention. This shows that a relatively large effective aperture ratio can be obtained in a range where the angle of the louver blades is shallow. Furthermore, FIG. 9 shows the results of a comparison of the rainwater infiltration rate between a conventional louver device having louver blades shaped as shown in FIG. 1 and a louver device according to the present invention. The louver device used in this experiment has a depth of 10 degrees and a louver blade angle of 30 degrees, and the louver blade of the present invention has a radius of curvature of a curved portion at the lower edge of the louver blade of 8 degrees. In Fig. 9, the curve K is for the slave, the curve L is for the present invention, and the width of the water receiving groove is 15 inches, and the depth is 15 inches, and the curve M is for the water receiving groove with a width of 15 inches. , five ribs deep. As is clear from this result, the intrusion rate of rainwater is significantly reduced in the case of the present invention compared to the conventional one, and even in the case of the present invention, the smaller the depth of the water receiving groove, the lower the intrusion rate of rainwater. It is shown that. Note that the present invention is not limited to the above embodiment. For example, the structure of the frame, the drain groove, the structures at both ends of the water receiving groove, etc. are not necessarily limited to those of the above embodiment.

Furthermore, the present invention is applicable not only to louver devices for air intakes in turbine buildings, but also to louver devices for air intakes in nuclear equipment buildings such as nuclear reactor buildings.

As described above, in the present invention, the lower edge of the louver blade is curved upwardly so as to be convex, and a water catcher is provided on the lower edge. Therefore, the raindrops that hit the lower edges of these louver blades are scattered outward, and the rainwater that flows down the top surface of these louver blades is collected in the water receiving groove and does not drip, so that the rainwater does not drop. The amount of water intrusion becomes extremely small. Therefore, this product can reduce the amount of rainwater that enters without increasing the angle of the louver blades or the width of the louver blades, and because the pressure loss is small, the area of the air intake port can be reduced, etc. is large.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional louver blade. Figures 2 to 6 show an embodiment of the present invention, with Figure 2 being a longitudinal sectional view, Figure 3 being a mm-m loss view of Figure 2, and Figure 4 being a partially enlarged view. FIG. 5 is an exploded perspective view, and FIG. 6 is a cross-sectional view of the louver blade to explain its function. 7th
The figure is a line diagram showing the relationship between the rainwater infiltration rate and the blade angle of a conventional louver device, Figure 8 is a line diagram showing the relationship between the blade angle and effective aperture ratio of one embodiment, and Figure 9 is a line diagram showing the relationship between the blade angle and the effective opening ratio of one embodiment. FIG. 7 is a diagram showing the relationship between the wind speed passing through the louver and the rainwater infiltration rate in an example. 1...
Turbine building (nuclear equipment building), 3... Louver device, 8... Louver blade, 15... Water receiving groove, 17...
Drainage ditch. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 7 Figure 8 Figure 9 Figure 6

Claims (1)

[Claims] 1. A frame attached to an air intake port of a nuclear equipment building;
In a louver device for an air intake of a nuclear equipment building, in which a plurality of louver blades are installed at intervals within the frame,
A louver device for an air intake of a nuclear power facility building, wherein the louver blade has a lower edge curved so as to be convex upward and has a water receiving groove at the lower edge. 2. The louver device for an air intake of a nuclear power facility building according to claim 1, wherein the depth of the water receiving groove is approximately 5 mm.