JPS6226435A - Snow suction preventive type outside air intake louver for atomic power plant - Google Patents

Abstract

PURPOSE:To prevent snow from making ingress into a building by using grid- like wire nets superimposed or each other in several sheets on the front surface of an outside air intake louver as a heating unit. CONSTITUTION:The louver comprises a snow screen 4 constituted by superimposing three sheets of mesh-like wire nets, terminals 10 installed for causing a current to flow through the screen 4, and louver vanes 2. In winter season, when snow falls, snow falling on the front surface of the louver is sucked up into the louver because snow power itself is light, and hence it is trapped by the snow screen 4. In order to positively trap the snow powder sucked up into the snow screen 4, the mesh interval is set to about 3mm by taking into consideration of the size of the snow powder. Since the wire nets are simultaneously made into conductive lines, a current is caused to flow from electric heating terminals 10 and the wire net is used as a heating unit, the trapped snow powder is increased of its temperature and is molten.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an outside air intake louver used as ventilation air conditioning equipment for nuclear power generation facilities, and particularly for nuclear power generation facilities installed in snowy areas such as the Sea of Japan side. This invention relates to an outside air intake louver that prevents snow from entering and is suitable for use in equipment.

[Background of the invention].

FIG. 3 shows a currently used outside air intake louver and its surrounding structure. The outside air passes through a bird screen 3, which is made of a wire mesh of approximately 10 mm and is attached to the outside air installation louver 1, and which is used to prevent large foreign objects such as birds from entering the building, and the louver blades 2. , dust is removed by a filter 5, and the air is supplied into the building by a supply fan 6. During snowfall, on the other hand, the snow covers the bird screen 3 and the louver blades 2.
By adhering to and enlarging, the outside air intake area decreases,
There is a problem in that the blade inflow speed increases, which not only causes vibration and noise, but also increases pressure loss in a portion of the louver, resulting in a decrease in the amount of outside air taken in. Furthermore, if the snow powder that has entered accumulates on the filter 5 and freezes, there is a possibility that the filter 5 will be damaged.

[Purpose of the invention]

The purpose of the present invention is to install a heating element made of multiplexed wire mesh in front of the outside air intake louver, and to collect and melt snow powder, thereby preventing snow from entering the building. An object of the present invention is to provide an outside air intake louver for nuclear power generation equipment that can prevent the above.

[Summary of the invention]

The present invention is designed to solve the problem that in winter, especially in nuclear power generation facilities installed on the Sea of Japan side where snowfall is heavy, snow enters through the outside air intake louvers, adheres to the filter, and freezes, resulting in a significant decrease in the performance of the filter. There are problems such as snow adhering to the front of the louver, which reduces the outside air intake area and makes the wind speed passing through the louver extremely high. Several mesh-like wire meshes are stacked on top of each other (on the outside of the building), and electricity is passed through them to generate heat.The wire mesh collects snow particles to prevent them from entering the building, and melts the snow that adheres to the building. This is what I did.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 2 is a view taken along the line A--A in FIG. 1. The outside air intake louver 1, which prevents snow from entering, includes a snow screen 4 made up of three overlapping mesh-like wire meshes, and a terminal 10 installed to allow current to flow through the snow screen 4. and louver blades 2.

As shown in FIG. 2, the snow screen 4 is made by overlapping the wire meshes of each lattice-like mesh so that they do not overlap each other. Further, an electric heating terminal is installed at the end of the wire mesh so that an electric current can be passed through the wire mesh portion. Normally, fresh air for ventilation inside the building is 1
After removing the dust contained in the air with a filter 5, it is heated/cooled with a heating coil 6° and a cooling coil 7 as necessary, and then is sent to each room of the building by a blower 8. is supplied to.

The air flowing into the outside air intake louver 1 has a surface velocity of approximately 1,
The inflow wind speed between the louver blades 2 is designed to be approximately 3 m/s to 4 m/s. During winter, when it snows, the snow particles themselves are light, so
Snow falling on the front of the louver is blown into the louver and collected on the snow screen 4. The snow screen 4 has meshes spaced approximately 3 mm apart, taking into consideration the thickness of the snow particles, so that the blown snow particles can be surely collected.

Since the wire mesh is arranged so that its linear shapes do not overlap each other, the mesh spacing is about lon or less. As a result, snow particles can now be collected almost reliably. It was also confirmed that this Snow Screen 4 has a great effect on the installation of rainwater.

This wire mesh also serves as a conductive wire, and a current is passed through the heating terminal 10 to become a heating element. The snow particles collected in the above manner are heated and melted. This makes it possible to prevent noise and vibration from occurring due to the air flow path being disturbed and the inflow speed increasing in some areas. Additionally, the molten water will flow through a wire mesh and out of the building, and will not flow into the building.

The wire mesh used as the heating element was made of nichrome wire covered with a waterproof covering, and only the outermost wire mesh among the three layers was used as the heating element. This is to facilitate maintenance and replacement of the heating element.

The second and third wire meshes were made of aluminum. It has been confirmed that this configuration is effective against snowfall of 8 am/h (Niigata region).

〔Effect of the invention〕

According to the present invention, a snow screen made of several layers of wire mesh is installed in front of the outside air intake louver, and by passing an electric current through this snow screen and using it as a heating element, the louver is heated as the outside air is taken in during snowfall. It can capture snow particles that try to invade and melt them, resulting in the following effects.

1. It prevents snow particles from entering the building, which prevents snow from accumulating inside the building, and also prevents snow from adhering to the filter, which is normally installed on the outflow side of the outside air intake louver, and causing it to freeze and cause the filter to become damaged. It is possible to prevent the occurrence of problems such as damage.

2. The effective air inflow entrance area of the louver will not be reduced due to snow adhering to and freezing on the front surface of the louver, thus preventing an increase in the vibration and noise of the louver blades due to an increase in the inflow speed on the louver blade surface. becomes possible.

3. During rainfall, the snow screen itself can efficiently collect rainwater, making it possible to significantly reduce the amount of rainwater entering the building.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining one embodiment of the present invention, and FIG.
A view taken along the line A--A in the figure and FIG. 3 are diagrams showing the structure of the conventional system. 1... Looper for outside air intake, 2... Louver blade,
3... Bird screen, 4... Snow screen, 5... Filter, 6... Heating coil, 7...
Cooling coil, 8... Air supply fan, 9... Air supply duct, 10... Electric heating terminal Figure 1 and Figure 2

Claims (1)

[Claims] 1. A louver for nuclear power generation equipment, characterized in that, in the outside air intake louver of the nuclear power generation equipment, several pieces of lattice-like wire mesh are superimposed on the front surface of the outside air intake louver, and the wire mesh is a heating element. Air intake prevention type outside air intake louver.