JP6638896B2 - Blast pressure reduction structure - Google Patents

Description

  The present invention relates to a structure for reducing a blast pressure that propagates outside through a ventilation duct or the like when a gas explosion occurs, for example.

  When an explosion accident occurs due to a gas leak or the like in an internal space (enclosed space, semi-enclosed space) 1 surrounded by a wall such as a basement, a strong pressure wave (shock wave) is generated in the internal space 1 (see FIG. 5). ). Further, the pressure wave is repeatedly reflected on a wall surface, a ceiling surface, a floor surface, or the like many times, and the multiple reflection of the pressure wave may cause enormous damage to equipment in the facility.

  For this reason, for example, in facilities that manufacture and store flammable gas such as hydrogen, measures to reduce the blast pressure by installing absorption plates that absorb pressure waves on the walls, ceiling, floor, etc. of enclosed spaces Has been proposed and put into practical use (for example, see Patent Document 1).

JP 2011-241541 A

  On the other hand, as shown in FIG. 5, when an explosion accident due to gas leakage or the like occurs in the internal space 1 surrounded by a wall such as a basement, a strong pressure wave generated in the internal space 1 The light propagates to the external space 4 through the communication path (opening) 3. At this time, if there is a house or a structure near the ventilation port 2, the strong pressure wave may damage the glass or the sash, or may cause human damage.

For this reason, it is required to reduce pressure waves emitted from the communication path 3 such as the ventilation port 2 as much as possible.
However, since the ventilation port 2 generally has a function of discharging the leaked gas, it is necessary to secure a certain opening area, and at present, the pressure wave released from the ventilation port 2 is reduced while being compatible with this function. There is no means available.

  In view of the above circumstances, the present invention can reduce a pressure wave that propagates to the outside in an explosion accident or the like through a communication path such as a ventilation opening that secures a certain opening area, for example, in order to ensure a leak gas discharge function and the like. An object of the present invention is to provide a blast pressure reducing structure.

  To achieve the above object, the present invention provides the following means.

The blast pressure reducing structure according to the present invention is configured such that a communication passage that communicates the internal space with the outside is formed in an annular shape that protrudes inward from the inner surface of the communication passage and is connected in the circumferential direction, and includes a plurality of resistance plates having the same inner diameter. It is characterized by being provided .

  Further, in the blast pressure reducing structure according to the present invention, it is preferable that an opening for introducing outside air into the inside of the communication path is provided outside the resistance plate.

  In the blast pressure reducing structure of the present invention, when an explosion occurs in the internal space, the blast pressure propagating to the outside through a communication path such as a ventilation port can be absorbed and attenuated by a resistance plate to be reduced.

It is a figure showing the blast pressure reduction structure concerning one embodiment of the present invention. It is a figure which shows the effect of reducing the blast pressure when changing the number of resistance plates. It is a figure which shows the reduction effect of the blast pressure when changing the space | interval of a resistance plate. It is a figure which shows the example of a change of the blast pressure reduction structure which concerns on one Embodiment of this invention, Comprising: It is a figure which shows the blast pressure reduction structure comprised with the opening part with the resistance plate. It is a figure which shows an example of the situation in which an explosion occurs in an internal space (closed space, semi-closed space), and a pressure wave is discharged | emitted from a ventilation opening etc. outside.

  Hereinafter, a blast pressure reducing structure according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5.

As shown in FIG. 5, the blast pressure reducing structure A of the present embodiment is provided in a communication path 3 that connects an internal space 1 such as a ventilation port 2 of a hydrogen production / storage facility to the outside 4. in a structure for reducing the strong pressure waves (shock waves / Bakufu圧) propagating through the communicating passage 3 when the explosion accident occurred.

  Specifically, as shown in FIG. 1, the blast pressure reducing structure A of the present embodiment includes an annular resistance plate 5 that protrudes radially inward from the inner surface of the communication passage 3 such as a duct and is connected in the circumferential direction. It is configured. In the present embodiment, a plurality of resistance plates 5 are provided at predetermined intervals in the extending direction of the communication passage 3.

  With the blast pressure reducing structure A of the present embodiment configured as described above, when an explosion occurs in the internal space 1, the pressure wave propagated to the outside 4 through the communication passage 3 is transmitted to the resistance plate 5. Due to reflection and diffraction phenomena due to

  Here, when the resistance plate 5 is installed in an aluminum alloy pipe (3) having an outer diameter d of 250 mm, a length L of 1500 mm, and a thickness of 10 mm, and changing the number and spacing of the resistance plates 5 The effect of reducing blast pressure was confirmed by simulation.

The results are shown in FIGS.
As shown in these figures, it was confirmed that the blast pressure was reduced when the number of the resistance plates 5 was increased, and that it was more effective when the interval was increased.

  Therefore, in the blast pressure reducing structure A of the present embodiment, when an explosion occurs in the internal space 1 of the closed space or semi-closed space, the blast pressure propagating to the outside 4 through the communication passage 3 such as the ventilation port 2 is reduced. The plate 5 allows the absorption and attenuation to be reduced.

  When the resistance plate 5 is provided in the ventilation opening 2, it is possible to reduce the blast pressure while maintaining the ventilation ability.

  As described above, one embodiment of the blast pressure reducing structure according to the present invention has been described, but the present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist thereof.

  For example, an uneven portion (notch or the like), a through hole, or the like may be provided on the resistance plate 5 to enhance the effect of reducing the blast pressure.

  As shown in FIG. 4, a resistance plate 5 is provided, and an opening 6 for introducing outside air into the inside of the resistance plate 5 of the communication passage 3 such as the ventilation port 2 is provided to reduce blast pressure. Structure A may be configured.

  In this case, due to the attraction effect of the flow in the communication passage 3, clean air (outside air) can be taken into the communication passage 3 from the outside through the opening 6, and the concentration of the gas G exhausted through the communication passage 3 is reduced. It becomes possible to do.

  Here, FIG. 4 shows the result of gas diffusion analysis performed by simulating the ventilation port 2 (communication passage 3) and the external space, and shows an iso-surface diagram (contour diagram) of the concentration of the gas G. . As shown in this figure, it has been confirmed that the gas concentration inside the ventilation port 2 is reduced by the outside air being drawn from the opening 6 provided on the side surface of the ventilation port 2.

  Therefore, by providing the opening 6 in addition to the resistance plate 5 as described above, for example, when an explosion accident occurs in an internal space (such as a semi-closed space) 1 surrounded by a wall such as a basement, the ventilation port 2 It is possible to reduce the pressure wave to be released and to reduce the concentration of gas discharged from the ventilation port 2 when a gas leakage accident or the like occurs in the internal space 1.

DESCRIPTION OF SYMBOLS 1 Internal space 2 Ventilation opening 3 Communication passage 4 Outside 5 Resistance plate 6 Opening A Blast pressure reduction structure

Claims (2)

A communication passage that communicates the internal space with the outside is formed in a ring shape that protrudes inward from the inner surface of the communication passage and is connected in the circumferential direction, and a plurality of resistance plates having the same inner diameter are provided. Blast pressure reduction structure. The blast pressure reducing structure according to claim 1,
A blast pressure reducing structure, wherein an opening for introducing outside air into the communication passage is provided outside the resistance plate.

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