JPH1170181A - Mist fire extinguishing system and fire extinguishing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance fire extinguishing performance by markedly improving the effect of cooling fire extinguishing and suffocated fire extinguishing by atomizing. SOLUTION: A spray head 1 for receiving the pressure supply of fire extinguishing water and spraying foggy mist is arranged in a guiard section 2, a motor-driven valve 6 is provided in a water supply duct 5 for pressurizing and supplying fire extinguishing water from a fire extinguishing pump equipment 3 to the spraying head 1 and a spray control part 11 controls the opening/closing of the motor-driven valve 6 at the time of fire so as to intermittently spray mist from the spraying head.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fine spray fire extinguishing system and a fire extinguishing method for extinguishing fire by spraying fine spray water having a particle diameter of about several tens to several hundreds of micrometers to a fire source.

[0002]

2. Description of the Related Art Conventionally, a fine spray fire extinguishing system has been used as a fire extinguishing system for a protection section such as a computer room which cannot cause water damage. The fine spray fire extinguishing system supplies fire fighting water to the spray head under pressure, and sprays fine spray with a particle size of several tens to several hundreds of micrometers toward the fire source, ensuring no water damage. Fire extinguishing system.

Hitherto, as a spray nozzle used in this type of fine powder fire extinguishing system, a fire extinguishing liquid composite jet nozzle that emits droplets having different particle sizes has been known (Japanese Patent Laid-Open No. 8-266).
676). In this injection nozzle, a fire extinguishing liquid having a large particle diameter of 70 μm to 400 μm is injected from the center of the nozzle, and a fire extinguishing liquid having a small particle diameter of 70 μm or less is injected around the nozzle. By the combined injection of the fire-extinguishing liquids with different particle diameters, the small-sized fine spray is applied to the flow of the large-sized central spray to reach the fire point, covering the fire source and suffocating / cooling fire extinguishing Let me.

[0004] In another conventional fine spray fire extinguishing system, water is sprayed by changing the particle size of water spray from a particle size in a mist state to a particle size in a raindrop state in proportion to the degree of progress of a fire. (JP-A-8-276028).

[0005]

The basic concept of the fine spray fire extinguishing system is to reduce the size of droplets used for fire extinguishing and increase the specific surface area to promote evaporation, and to evaporate heat during evaporation. To extinguish combustible gas from the combustion field by using a mechanism that removes combustible gas from a fire source, dilutes combustible gas with steam, dilutes oxygen concentration, or jets generated by spray pressure. .

Here, the specific surface area S when a fixed volume of water is sprayed from the spray head to form fine spray is defined as S = (surface area) / (volume). The droplet that has been finely sprayed is regarded as a sphere and the radius is r
Then, the specific surface area S becomes: (4πr ² ) / (4/3) (πr ³ ) = 3 / r, and the smaller the particle diameter r, the larger the specific surface area S can be.

For this reason, in the fine spray fire extinguishing system,
An important point is how to efficiently evaporate the fine spray water injected into the fire source in a high-temperature space caused by a fire. That is, the scale of the fire source, the droplet size of the fine spray, the initial momentum of the droplet, the relative position between the spray head and the fire source, and the like are important points for determining the fire extinguishing ability. Further, according to the consideration based on the fire experiment of the inventor of the present application, it is considered that the evaporation of the finely sprayed droplets takes away the heat of vaporization from the fire source and cools and extinguishes the fire, and the evaporating steam covers the fire source and extinguishes the suffocation, It was found that the effect was achieved only when the finely sprayed droplets were evaporated by the heat of the fire source, and that the fire immediately after the start of the fine spray exerted the greatest fire-extinguishing effect at the greatest time.

That is, when a fine spray is jetted into a space sufficiently heated by a fire flame, a large amount of evaporation is instantaneously performed.
A large amount of heat is taken away by the heat of vaporization. Also,
Since the dilution of oxygen and flammable gas was performed simultaneously with the evaporation and in a short time, it was found that the fire extinguishing effect was extremely high immediately after the start of the discharge of the fine spray. Therefore, when an attempt was made to extinguish a flammable liquid fire in an open space using a fine spray, most of the fire was extinguished shortly after the release of the fine spray. It has been found that there is little possibility of extinguishing the fire even if it is continued.

[0009] However, the conventional fine spray fire extinguishing system is a fire extinguishing method in which fine spray is continuously sprayed until the fire is extinguished. In such a fire extinguishing method, the effect of cooling and suffocation extinguishing by the fine spray is sufficient. Can't expect. The present invention
The present invention has been made in view of such conventional problems, and provides a fine spray fire extinguishing system and a fire extinguishing method in which the effects of cooling and suffocating by fine spray are greatly improved to enhance the fire extinguishing performance. With the goal.

[0010]

In order to achieve this object, a fine spray fire extinguishing system according to the present invention is installed in a protective section, and receives a pressurized supply of water for fire extinguishing to spray mist fine spray. Spraying head, pump equipment for pressurizing fire-extinguishing water to the spraying head, a motorized valve provided in a water supply pipe for pressurizing fire-extinguishing water to the spraying head, and a spraying head by controlling opening and closing of the motorized valve in case of fire A fine spray control unit for intermittently discharging fine spray is provided.

According to such a fine spray extinguishing system of the present invention, by discharging the fine spray intermittently, instantaneous droplets at the time of discharge can be reduced as compared with the conventional case where fine spray is continuously discharged. Can be greatly increased. In addition, since the discharge energy is concentrated at the time of discharge, a relatively small fire pump can impart a large momentum to the droplet.

The fire extinguishing effect by the fine spray is brought about by the cooling and suffocating effect by evaporation of the fine droplets.
The effect of evaporating the fine droplets is greater during the largest fire period immediately after spraying, and fire is most likely to be extinguished. Further, by performing the fine spraying intermittently, spraying with a high fire extinguishing effect can be repeated, and the possibility of fire extinguishing can be dramatically increased.

[0013] Further, intermittent injection makes more effective use of water than continuous injection of fine spray, and the power of the fire pump can be used more effectively. The fine spray control unit detects the water supply pressure of the water supply pipe, controls the electric valve to be in the open state while the water supply pressure is equal to or higher than the specified pressure Pr, and sprays fine spray from the spray head, and the water supply pressure falls below the specified pressure Pr. During this time, the injection of the fine spray is stopped by controlling the electric valve to the closed state.

The fine spray control unit detects the water supply pressure P of the water supply pipe and sets a specified lower limit value P1 and an upper limit value P2. When a fire is detected, the control unit opens the motor-operated valve if the lower limit value P1 or more. And spraying fine spray from the spray head. When the value falls below the lower limit value P1 during spraying, the electric valve is controlled to a closed state to recover water supply pressure by stopping the spraying, and when the recovered water supply pressure exceeds the upper limit value P2, the motor is operated. The valve may be controlled to be in the open state to spray fine spray from the spray head, and this may be repeated.

Further, the present invention provides a spray head installed in a protection section, which receives pressurized supply of fire-extinguishing water and sprays fine atomized mist, a pump facility for pressurizing fire-extinguishing water to the spray head, The present invention provides a fire extinguishing method for a fine spray fire extinguishing system including a motorized valve provided in a water supply pipe for pressurizing fire extinguishing water to a head. In the event of a fire, a fine spray of fire extinguishing water is intermittently ejected from a spray head in a fire. It is characterized by the following.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory diagram of a system configuration to which a fine spray fire extinguishing system and a fire extinguishing method according to the present invention are applied. In FIG. 1, a spray head 1 is installed in a ceiling portion of a protection section 2 such as a computer room, and a water supply pipe 5 from a fire extinguishing pump 3 is connected to the spray head 1 via an electric valve 6. The fire pump 3 pressurizes, for example, fire-extinguishing water in the water source water tank 4 to a specified pressure and supplies it to the spray head 1, and discharges the fire source F as fine spray having a particle size in the range of several tens to several hundreds of μm.

An accumulator 7 is connected to the water supply pipe 5, and when the electric valve 6 is opened by the accumulator 7 to release the fine spray from the spray head 1, the water supply pressure by the water supply pipe 5 suddenly increases. It prevents it from dropping. Electric valve 6 provided in water supply pipe 5 of spray head 1
Is controlled by the control panel 10 to open and close. A fire detector 8 installed in the protection section 2 is connected to the control panel 10,
A pressure sensor 9 for detecting the pressure of the water supply pipe 5 is connected, and a motor of the fire pump 3 is also connected. The control panel 10 includes a fine spray control unit 11 that realizes a fire extinguishing method of the fine spray fire extinguishing system of the present invention realized by an MPU or the like.

The fine spray controller 11 includes, for example, the fire detector 8
If the fire of protection section 2 is judged based on the alarm signal of
After starting the fire pump 3, the pressure sensor 9 detects the water supply pressure P of the water supply pipe 5 and sets the spray head 1 set in advance.
When the pressure is equal to or higher than the specified pressure Pr that is more suitable for the ejection of the fine spray, the motor-operated valve 6 is controlled to open when the pressure is equal to or higher than the specified pressure Pr. Fire source F is performed.

The fine spray control section 11 is characterized in that the fine spray is intermittently ejected from the spray head 1 by controlling the opening and closing of the electric valve 6. Regarding the intermittent release of this fine spray, the fine spray control unit 11
Is controlled by comparing the supplied water pressure P with the specified pressure Pr. That is, while the supply water pressure P is equal to or higher than the specified pressure Pr, the electric valve 6 is controlled to be in the open state, and the spray head 1 discharges fine spray.

In the fine spray fire extinguishing system of the present invention,
The amount of pressurized fire-extinguishing water supplied by the fire pump 3 is reduced with respect to the amount of water sprayed by continuous spraying. As a result, when spraying is continued, the feed water pressure P decreases. When the water supply pressure P during spraying from the spray head 1 falls below the specified pressure Pr, the fine spray control unit 11 of the control panel 10 closes the electric valve 6 to the fully closed state.

When the spraying of the fine spray from the spray head 1 is stopped by closing the electric valve 6, the feed pressure P of the feed water pipe 5 recovers, and when the feed pressure again becomes equal to or higher than the specified pressure Pr, the fine spray control unit 11 starts to operate. The electric valve 6 is controlled to open, and the spray of the fine spray from the spray head 1 is performed again. By repeating this, fine spray of fire-extinguishing water is intermittently discharged from the spray head 1 toward the fire source F.

FIG. 2 is a time chart of the intermittent discharge control from the spray head 1 by the fine spray control unit 11 provided in the control panel 10 of FIG. 1. FIG. FIG. 2B shows a fire alarm signal of the fire detector 8, and FIG. 2C shows the open / closed state of the motor-operated valve 6. Now, at time t1, when the fire alarm signal from the fire detector 8 is turned on, the fine spray control unit 11 provided on the control panel 10
Starts the fire pump 3 and reads the feed water pressure P from the pressure sensor 9 at this time. In the steady monitoring state up to time t1, the feed water pressure P is maintained to be equal to or higher than the specified pressure Pr. Therefore, when the fire alarm signal is turned on at time t1, the pressure is equal to or higher than the specified pressure Pr. The fine spray control unit 11 controls the electric valve 6 to open and fully open.

As a result, the spray head 1 discharges the fine spray of pressurized fire extinguishing water to the fire source F. When the fire-extinguishing water is discharged by the fine spray, the water supply pressure P decreases and falls below the specified pressure Pr at time t2. Therefore, the fine spray control unit 11 closes the electric valve 6 to the fully closed state. When the electric valve 6 is controlled to be fully closed, the feed water pressure P is restored again, and at time t3, exceeds the specified pressure Pr. Head 1
The discharge of the fine spray is started again. Hereinafter, the opening and closing of the motor-operated valve 6 is repeated according to the change of the water supply pressure P accompanying the discharge and the stop of the fine spray from the spray head 1, and the fine spray is intermittently repeated from the spray head 1.

By repeating the emission of the fine spray from the spray head 1 in this manner, the fire extinguishing of the fire source F is effectively performed every time the fine spray is emitted, and by repeating this, the fire can be efficiently extinguished. In particular, in the intermittent release of the fine spray according to the present invention, the amount of instantaneous raindrops released at the time of release is greatly increased as compared to the continuous release of the conventional fine spray, and the discharge is emitted to the fire source F in a wavy manner. Effective fire extinguishing. In addition, the discharge energy can be concentrated on the fire source F by the intermittent wave discharge, and a large kinetic energy can be given to the droplet ejected by the fire pump 3 having a relatively small capacity.

FIG. 3 is a flowchart of the fine spray control section 11 provided in the control panel 10 of FIG. 1 for performing the intermittent discharge control of the fine spray shown in the time chart of FIG. First, step S1
The presence or absence of a fire alert is checked by, for example, if it is determined that there is a fire alert based on an alert signal from a fire detector 8 installed in the protection section 2, the process proceeds to step S2 and the fire pump 3 is started. . Subsequently, at step S3, it is checked whether or not the feed water pressure P is equal to or higher than a specified pressure Pr. If the pressure is equal to or higher than the specified pressure Pr, the process proceeds to step S4, in which the electric valve 6 is controlled to open.
The spray head 1 causes a fine spray to be emitted to the fire source.

If the motor-operated valve 6 is controlled to be opened, step S
At 5, it is monitored whether or not the feed water pressure P falls below the specified pressure Pr. When the pressure falls below the specified pressure Pr, at step S 6, the electric valve 6 is controlled to close and the discharge of the fine spray from the spray head 1 is stopped. Subsequently, in step S7, a system stop command by an operator or the like based on fire suppression is checked, and if there is no system stop command, the process returns to step S3 and repeats the opening / closing control of the electric valve again.

When a system stop command based on fire suppression confirmation is determined in step S7, system stop processing such as stopping the fire pump 3 and closing the motor-operated valve 6 is performed in step S8, and a series of processing ends. FIG. 4 is a time chart of another embodiment by the fine spray control unit 11 of FIG. In the embodiment of the time chart of FIG. 4, FIG.
As shown in (A), a predetermined lower limit value P1 and a predetermined upper limit value P2 are set for the feed water pressure P in the fine spray control unit 11, and the upper and lower limits P1, P2 are compared with the feed water pressure P to open and close the electric valve 6. It is characterized in that control is performed.

That is, when the fire alarm signal from the fire detector 8 is turned on at time t1, the fine spray control unit 11 starts the fire pump 3 and then checks the water supply pressure P with the pressure sensor 9. At this time, since the feed water pressure P is in the range of not less than the lower limit value P1 and not more than the upper limit value P2, the electric valve 6 is controlled to open to discharge fine spray from the spray head 1. When the feed water pressure P decreases due to the release of the fine spray from the spray head 1 and falls below the lower limit P1 at time t2, the electric valve 6 is controlled to close to stop the discharge of the fine spray from the spray head 1.

By stopping the discharge of the fine spray, the feed water pressure P is recovered, and at time t3 when the upper limit value P2 is reached, the electric valve 6 is controlled to open again to discharge the fine spray from the spray head 1. When the discharge of the fine spray from the spray head 1 is started, the pressure P in the pipe decreases, and when the pressure falls below the lower limit P1 at time t3, the electric valve 6 is closed. In the same manner, the opening / closing control of the electric valve 6 based on the change of the feed water pressure P is performed, and the spray head 1 intermittently discharges the fine spray from the spray head 1 to the fire source F. By thus increasing the pressure at the time of spraying, the momentum of the droplet can be increased, and the fire extinguishing effect can be enhanced.

FIG. 5 is a flowchart of another embodiment of the fine spray control unit 11 provided in the control panel 10 of FIG.
This embodiment is characterized in that the opening / closing control of the motor-operated valve 6 is performed by setting a timer. First, in step S1, when a fire alarm is determined based on a fire alarm signal from the fire detector 8, the fire pump 3 is started in step S2, and it is checked in step S3 whether the pressure is equal to or higher than a specified pressure Pr.

If the pressure is equal to or higher than the specified pressure Pr, the scheduled fine spray can be released from the spray head 1. Therefore, the process proceeds to step S4, in which the electric valve 6 is controlled to open, and the fine spray is Release toward F. Upon completion of the electric valve opening control, in this embodiment, a timer in which the specified time T1 is set is started, and the elapse of the specified time T1 is checked in step S5.

When the specified time T1 has elapsed, step S6 is executed.
To control the closing of the electric valve 6 to stop the emission of fine spray from the spray head 1. When fully closed by this motorized valve closing control,
The timer of the specified time T2 is started, and the elapse of the specified time T2 is determined in step S7. After the lapse of the specified time T2, it is checked in step S8 whether there is a system stop command. If there is no system stop command, the process returns to step S4 to open the electric valve 6 again, and so on.

That is, in the control processing of the flowchart of FIG. 5, the motor-operated valve 6 is kept open for a specified time T1,
Subsequently, the electric valve 6 is closed for a specified time T2 to control the opening and closing, so that the fine spray from the spray head 1 is intermittently discharged. The intermittent release of the fine spray from the spray head 1 by the fine spray control unit 11 of the present invention is not limited to the control by the water supply pressure P and the timer set time shown in the above-described embodiment. If the discharge of the fine spray is performed intermittently, an appropriate control process can be adopted.

The fire pump 3 in the above embodiment
If the capacity of the spraying head 1 is sufficiently large compared to the amount of the fine spray discharged from the spray head 1, since the drop of the water supply pressure P hardly occurs due to the discharge of the fine spray, the discharge time setting timer T1 and the discharge stop time setting timer T2 Only by setting the time, the fine spray can be intermittently discharged. In this case, it is desirable that the release time T1 is set in a range of, for example, 5 to 10 seconds, and the release stop time T2 is set in a range of 20 to 30 seconds in consideration of water loss.

[0035]

As described above, according to the present invention, by intermittently discharging the fine spray, the cooling and suffocating effects of the fine spray confirmed by the present inventors through fire extinguishing experiments can be applied to the fire immediately after spraying. Bigger in the greatest period of
The advantage of increasing the possibility of fire extinguishing is fully utilized, and fire extinguishing performance can be dramatically improved by repeating intermittent discharge of fine spray.

The intermittent release of the fine spray according to the present invention greatly increases the instantaneous amount of the liquid droplets compared to the conventional case where the fine spray is continuously discharged. Giving a large amount of kinetic energy to droplets discharged by a small-capacity fire pump, it can penetrate sufficiently into a combustion field even under hot air flow, and can extinguish fire efficiently.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a fine spray fire extinguishing system of the present invention.

FIG. 2 is a time chart of the intermittent injection of the fine spray head based on the detected pressure of FIG.

FIG. 3 is a flowchart of fine spray fire extinguishing control based on the detected pressure in FIG. 1;

FIG. 4 is a time chart of another embodiment of the intermittent injection of the fine spray head based on the detected pressure of FIG. 1;

FIG. 5 is a flowchart of fine spray extinguishing control by setting a timer in FIG. 1;

[Explanation of symbols]

 1: Fine spray head 2: Protective section 3: Fire pump 4: Water tank 5: Water supply pipe 6: Electric valve 7: Accumulator 8: Fire detector 9: Pressure sensor 10: Control panel 11: Fine spray control unit 13: Pressure Sensor

Claims (4)

[Claims] 1. A spray head installed in a protection section and receiving a pressurized supply of fire-extinguishing water to spray fine atomized mist, a pump facility for pressurizing fire-extinguishing water to the spray head, and the spraying head. An electric valve provided in a water supply pipe for supplying pressurized water for fire extinguishing to a water supply pipe; and a fine spray control unit that controls opening and closing of the electric valve in the event of a fire to intermittently eject fine spray from the spray head. A fine spray fire extinguishing system characterized by the following. 2. The fine spray extinguishing system according to claim 1, wherein the fine spray control unit detects a water supply pressure of the water supply pipe, and opens the electric valve while the water supply pressure is equal to or higher than a specified pressure. Controlling to spray fine spray from the spray head,
The fine spray fire extinguishing system, wherein the electric valve is controlled to be closed to stop the injection of the fine spray while the supply water pressure is lower than the predetermined value. 3. The fire-extinguishing system according to claim 1, wherein the spray control unit detects a water supply pressure of the water supply pipe and sets an upper limit value and a lower limit value of a specified pressure. If the lower limit is equal to or more than the lower limit, the electric valve is controlled to be in the open state to spray fine spray from the spray head. A fine spray fire extinguishing system wherein the feedwater pressure is recovered, and when the recovered feedwater pressure exceeds the upper limit, the electric valve is controlled to be in an open state to spray fine spray from the spray head, and this is repeated. 4. A spray head installed in a protection section and receiving a pressurized supply of fire-extinguishing water to spray fine atomized mist, a pump facility for pressurizing the fire-extinguishing water to the spray head, and the spraying head. A fire-extinguishing method for a fine-spray fire-extinguishing system, comprising: a motor-operated valve provided in a water supply pipe for pressurizing fire-extinguishing water to the fire-extinguishing water. A fire extinguishing method for a fine spray fire extinguishing system.