WO2018032498A1

WO2018032498A1 - Method and system for pressurizing, supplying air, and blocking smoke in high-rise building stairwell

Info

Publication number: WO2018032498A1
Application number: PCT/CN2016/095984
Authority: WO
Inventors: 纪杰; 李曼; 原向勇; 高子鹤; 杨立中; 万华仙
Original assignee: 中国科学技术大学
Priority date: 2016-08-19
Filing date: 2016-08-19
Publication date: 2018-02-22

Abstract

Provided is a method for pressurizing, supplying air, and blocking smoke in a high-rise building stairwell; the high-rise building has a plurality of stories, and the stories are connected to each other by means of the stairwells (4); a plurality of air supply vents (11) are distributed in the stairwells (4), and the air supply vents (11) are used for supplying air to the stairwells (4). The method comprises the following steps: S1: detecting whether a fire has occurred at each story of a high-rise building; S2: if, in step S1, a fire is detected on a story of the high-rise building, then causing only the two or three nearest air outlets to supply air. The system used by the method comprises a fire detector (1a) and a system controller (1b); if the fire detector (1a) detects the occurrence of a fire on a story of the high-rise building, then a fan (9) and air supply vent (11) are automatically activated by means of linked control. In the method and system it is possible to block, using a smaller amount of supplied air, the smoke generated by the power of the same fire source of any stories on fire from entering the stairwell, thus minimizing the effect of air leaking between stairwells as a result of the number and positions of openings of fire doors between the stairwells.

Description

Method and system for pressurized air supply and smoke blocking in stairwell of high-rise building

Technical field

The invention belongs to the technical field of fire safety, and particularly relates to a situation in which a fire zone is detected in a high-rise building, and after detecting a fire floor, the position and the number of air supply openings opened near the fire floor are adjusted, and only the stairwell is taken. Positive pressure air supply, a smoke blocking method and system that can block fire smoke from entering the stairwell.

Background technique

With the development of the economy, the number of high-rise buildings is increasing year by year, the building height is also increasing, and the structure is becoming more and more complicated. Among them, the Shanghai Tower has a total of 125 floors and a height of 632m, which is the tallest building in China; Tianjin Gaoyin 117 Building is 596.5m high; the World Financial Center is 492m high. While high-rise buildings bring convenience to modern cities, they also bring more problems to building fire prevention work. There are a large number of vertical passages in high-rise buildings, such as elevator shafts, stairwells, pipeline wells, and cable wells. Once a fire occurs in the room, the high-temperature hot flue gas generated by the combustion enters these shafts and is prone to a “chimney effect”. The fire source flue gas spreads from the lower layer of the building to the upper layer and even the entire high-rise building under the action of the “chimney effect”. A large number of casualties and property losses were caused and the evacuation of personnel in high-rise buildings was affected. Therefore, in the fire environment, measures are taken to protect the evacuation passages such as stairwells, and delaying the spread of smoke is extremely important for fire rescue work.

Since 1960, the use of positive pressure air supply has been widely used to protect stairwells, providing a smoke-free safe passage for evacuation and fire rescue in high-rise buildings. The core idea is relatively simple, increasing the internal pressure of the stairwell, so that the pressure difference between the inside and outside of each step of the stairs is maintained at a positive value to prevent the smoke from spreading to the inside of the stairwell. Tamura and Klote believe that the positive pressure air supply system is turned on and continuously operated before the smoke spreads to the stairwell, so that the internal pressure of the stairwell is stronger than the pressure value under the chimney effect. At this time, the air supply volume of the positive pressure air supply system can be minimized. The air supply value. At present, the amount of pressurized air supply can be calculated by means of the average air volume method, the door wind speed method, the differential pressure method, the gap method, and the like. China’s “Code for Fire Protection Design of High-Rise Civil Buildings” stipulates that buildings of less than 20 floors, The pressurized air supply of the smoke-proof stairwell should be 25000-30000m3/h.

The "Code for Fire Protection Design of High-rise Civil Buildings" stipulates that a pressurized air supply port is provided on each floor of the front room, and an air supply port is provided for every 2-3 floors in the stairwell. For the structure of the front room separately used in the stairwell, there are three main methods of positive air supply: only the front room is supplied with air, only the stairwell is supplied with air, and the stairwell and the front room are simultaneously pressurized and supplied with air. When the air is blown to the front room, only the air supply opening of the fire floor is opened during the air supply; when the wind is supplied to the stairwell, all the air supply openings are opened during the air supply.

In the actual operation process, the positive pressure air supply system will be affected by many factors, and the smoke blocking effect on the stairwell will not reach the expected target. For example, when the air supply to the stairwell of a high-rise building is pressurized, during the evacuation process, multiple fire doors in the stairwell may be simultaneously opened, causing the airflow in the stairwell to leak and fail to effectively block the smoke. Through numerical simulation research, it is found that under the air supply volume specified by the specification, when two or two lower fire doors are opened in the stairwell, the smoke can be blocked from entering the stairwell, but when the number of fire door openings in the stairwell reaches three, it will appear. Smoke failure. It can be seen that when the number of openings in the stairwell fire door is greater than or equal to three, the conventional positive pressure air supply method can no longer meet the demand for smoke blocking.

Summary of the invention

The object of the present invention is to provide a method and a system for pressurizing air supply and smoke blocking in a stairwell of a high-rise building, which can block the same size of fire source with less air supply volume, and even if multiple openings of the stairwell fire door are simultaneously in the evacuation process In the presence and different fire floors, the smoke is effectively prevented from entering the stairwell, and the influence of the number and position of the fire door openings in the stairwell on the stairwell leakage is minimized.

The stairwell pressurized air blower method proposed by the invention is applicable to a high-rise building, which has multiple floors, and each floor is connected by a stairwell, and a plurality of air outlets are arranged in the stairwell, and each air supply port is used for stairwell Air supply, the method includes the following steps:

S1. Detecting whether a fire occurs in each layer of the high-rise building;

S2. When it is detected in step S1 that a fire occurs in a certain layer of the high-rise building, only two or three air outlets closest to the floor are supplied with air.

Preferably, the fire detector is used to detect the fire in step S1.

Preferably, in step S1, the fire detector generates a signal to a system controller when detecting the fire to report the layer number at which the fire occurred to the system controller; in step S2, the system controls The device only sends air to two or three air outlets in the stairwell near the layer number indicated by the signal, and the other air outlets do not supply air.

Preferably, each of the air supply ports is connected to a air supply duct, and the air supply duct is connected to a fan. When a specific air supply port is required to be blown, in step S2, the system controller automatically controls to turn on the fan, and Open the air supply port that needs to be supplied with air, and close the other air supply ports.

Preferably, the opening and closing of the air blowing ports are controlled by the system controller.

The invention also provides a stairwell pressurized air supply and smoke blocking system applied to a high-rise building. The high-rise building has a plurality of floors, and each floor is connected by a stairwell, and a plurality of air supply openings are distributed in the stairwell, and each is sent a tuyere for supplying air to the stairwell, the system comprising: a fire detector disposed at each floor of the high-rise building for detecting whether a fire occurs in each floor of the high-rise building; a system controller When the fire detector detects that a fire occurs in a certain layer of the high-rise building, only the two or three air supply openings closest to the floor are supplied with air.

(1) The present invention provides a basis for the targeted increase of the local pressure near the most dangerous floor in the stairwell by accurately locating the fire source floor.

(2) The present invention concentrates the air volume on the fire floor, and can increase the effective pressure of the smoke block on the fire floor in the stairwell, and can block any fire floor with less air supply than the conventional positive pressure air smoke control method. Smoke from the same source of power enters the stairwell.

(3) The invention increases the partial pressure near the maximum floor in the stairwell, and the pressure on other floors is basically unchanged, and the air leakage leaked from the fire door opened in the stairwell of other floors is greatly reduced, and the fire door opening of the stairwell can be opened. The number and location cause the impact of air leakage to be minimized.

DRAWINGS

1 is a schematic view showing the overall structure of a building and air supply system in a method for pressurizing air supply and smoke blocking in a stairwell of a high-rise building according to the present invention;

2 is a schematic structural view of an embodiment of a system of the present invention;

Figure 3 is a flow chart of the present invention;

Figure 4A is a schematic view showing the flow of the air flow of the air supply system when the fire source is in the first layer, the first, third and fifth layers of the fire door are opened;

Fig. 4B is a schematic view showing the flow passage of the air supply system of the air supply system when the first, seventh and ninth fire doors are opened in the first layer;

Fig. 5A is a schematic diagram showing the flow of smoke generated by the numerical simulation of the first, third and fifth layers of fire doors when the fire source is in the first layer;

Fig. 5B is a schematic diagram showing the flow of smoke generated by the numerical simulation of the first, seventh and ninth fire doors when the fire source is in the first layer;

Figure 6 is a schematic view showing the flow of the air flow of the air supply system when the fire source is at the seventh floor, the fire doors of the first, seventh and ninth floors are all opened;

Fig. 7A is a schematic diagram showing the flow of smoke generated by the numerical simulation of the first, seventh and ninth fire doors when the fire source is at the seventh floor;

Fig. 7B is a schematic diagram showing the flow of smoke generated by the numerical simulation of the first, seventh and ninth fire doors when the fire source is at the seventh floor, changing the position of the three air supply openings;

Fig. 7C is a schematic diagram showing the flow of flue gas obtained by numerical simulation of the first, seventh and ninth fire doors when the fire source is at the seventh floor, changing the position of the two air supply openings;

Fig. 8 is a schematic view showing the flow passage of the air supply system of the air supply system when the fire source is on the 12th floor, the fire doors of the first, seventh, ninth and twelfth floors are all opened;

Figure 9 is a schematic diagram of the flow of flue gas obtained by numerical simulation of the fire barriers using the fire dynamics simulation software FDS when the fire source is on the 12th floor;

In the figure, the label: 1a-fire detector; 1b-system controller; 2-room; 3-front room; 4-staircase; 5-room door connected to the outside world; 6-door door connected to the front room; - the door connected to the stairwell in the front room; 8-stairs pedal; 9-fan; 10-air supply duct; 11-air supply port; 12-fire source; 13-wind flow route, the solid line is the must-have route of the wind flow, the dotted line is Optional route.

detailed description

In the high-rise building, when the front room is used alone in the stairwell, in order to effectively prevent the fire source from spreading into the stairwell and affecting the evacuation and fire rescue, the present invention proposes a method for pressurizing the windshield in the stairwell of a high-rise building and correspondingly system.

Each of the high-rise buildings referred to in the present invention includes at least a stairwell, and each floor is connected by a stairwell. Each floor usually has a room, and if there is a room on one floor, there is often a door between the stairwell and the room. However, the present invention is not limited thereto, and the present invention is also applicable to other more complicated buildings, such as the case where a front room is provided in front of a stairwell and a room, at this time, between the stairwell and the front room, between the front room and the room. There is also a door. The invention can also be extended to other similar buildings as long as there are stairwells connected up and down in the building.

The invention firstly requires an air supply port every two to three floors in the stairwell of the high-rise building, and the air supply port is used for pressurizing the air supply into the ladder room. Moreover, the present invention requires that each air supply port is controllable whether the air supply is performed, that is, the air supply port can be switched on or off by an automatic control system or an artificial operation to switch the state of the air supply and the air supply.

In general, the stairwell pressurized air blower method of the present invention comprises the following steps:

S1. Detecting whether a fire occurs in each layer of the high-rise building;

Open the air supply opening in the vicinity of the fire floor. The main purpose is to reduce the number of open air outlets and increase the effective pressure of the fire floor to block smoke. The smoke blocking effect is best when two or three air outlets near the fire floor are opened.

In step S1, a fire detector can be used to detect the fire. Existing smoke detectors or temperature detectors can be used. For example, a fixed temperature detector, a differential temperature detector or a differential temperature detector can generate a signal to a system controller to detect the fire. The device reports the layer number at which the fire occurred. In step S2, the system controller controls the fan to automatically open and blow the air supply port in the stairwell of the layer number indicated by the signal, and the other air supply ports do not supply air. The system controller can be realized by the linkage controller, with the microcontroller as the core, the non-volatile random access memory (NV-RAM) is used to store the field programming information, and the remote connection is realized through the RS-485 serial port, which can realize various Linkage control logic.

Usually, the air supply openings of each stairwell are connected to a supply duct, which is connected to a fan, and the fan can be arranged at the top or bottom of the high-rise building. The opening and closing of each air supply port is controlled by the system controller. When a specific air supply port is required to be blown, turn on the fan, and open the air supply port that needs to be supplied with air, and close the other air supply ports.

The fire detector, the system controller, the air supply port and the fan are connected by a line for signal transmission. Since signal generation, conversion, and the like are all prior art, they will not be described in detail herein.

Compared with the conventional positive pressure air supply and smoke prevention method, the present invention can block the smoke generated by the same fire source power of any ignition floor from entering the stairwell with less air supply. It is also possible to minimize the effects of the number and location of fire door openings in the stairwell causing air leaks in the stairwell. Moreover, the fire occurs on any floor, and the invention can effectively block the fire source from entering the stairwell, and is not limited to blocking the fire source of a certain floor.

The present invention will be further described in detail below with reference to the specific embodiments of the invention,

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing the overall structure of a floor of a high-rise building to which an embodiment of the present invention is applied. As shown in Figure 1, the high-rise building has 12 floors, each of which includes room 2, front room 3 and stairwell 4. The room 2 is connected to the outside by a first door 5, the front room 3 is connected to the room 2 by a second door 6, and the stairwell 4 is connected to the room 3 by a third door 7. There are stair steps 8 in the stairwell.

2 is a schematic block diagram of one embodiment of the system of the present invention. As shown in Fig. 2, the positive pressure air supply system of the present invention includes a fire detector 1a and a system controller 1b, which are connected by a line. In addition, the building facilities cooperating with the system include a fan 9 at the top of the building, a supply duct 10, and air outlets 11 of each floor. Both the fan 9 and the air supply port 11 are communicatively coupled to the system controller 1b and are controlled to be turned on and off by the system controller.

Figure 3 is a block flow diagram of the method of the present invention. As shown in FIG. 3, each layer of the fire detector 1a detects the fire in real time. When at least one fire detector 1a detects the fire, it sends an alarm signal to the system controller 1b, and the alarm signal includes information of the fire source floor. The system controller 1b confirms the floor where the fire occurred based on the signal, controls the fan 9 to be turned on, and controls the air supply port 11 near the corresponding fire source floor to be turned on. The system controller 1b issues a control signal to confirm the fire. Before, you can also confirm whether the fire detector 1a has a false alarm, that is, whether there is a fire in the corresponding room.

In this embodiment, the system controller 1b turns on the fan and controls the air supply port 11 of the stairwell near the fire source floor to perform positive pressure air supply to the stairwell. 4A and 4B respectively show the case when the fire source is in the first layer, wherein FIG. 4A shows the case where the fire doors (the third door 7) of the first, third, and fifth floors are both opened, and FIG. 4B shows the

The

1, 7, and 9-story fire doors (the third door 7) are all open. As shown in FIGS. 4A and 4B, in the case where a plurality of third doors 7 are opened in the stairwell, regardless of the position of the third door 7, when the fire source 12 is located on the first floor, two adjacent ones above the first layer are opened. The tuyere 11, that is, the air outlets of the second and third floors, and the air outlet of the fourth layer are selectively openable (the solid line indicates the air blowing direction, and the broken line indicates the optional air blowing direction). The air flow 13 enters the stairwell 4 from the open two or three air supply ports 11 through the air duct 10, and the pressure below the stairwell 4 is increased, so that the fire source smoke can be effectively prevented from entering the stairwell 4.

5A and 5B are schematic views respectively simulating the smoke blocking method of Figs. 4A and 4B. As shown in FIG. 5A, the fixed air supply amount is 25000 m ³ /h, and from left to right, the smoke shielding effect diagrams of

opening

6, 4, 3, and 2 air outlets are respectively, wherein the air supply port 11 is not filled. Indicates that the air supply opening is open, and the shadow filling indicates that the air supply opening is closed. Under the conventional positive pressure air supply method (opening 6 air supply ports 11), the increased pressure in the stairwell cannot overcome the effect of the chimney effect, and the flue gas enters the stairwell 4 through the

open door openings

6, 7 and spreads to the uppermost position. Opening 7. If the number of air outlets in the stairwell is reduced, the lower four air supply ports 11 are opened, the smoke cannot enter the stairwell 4, but there is a large amount of flue gas in the front chamber 3; when the method of the present invention is used to open the lower 2 or 3 air supply ports 11, even if There is only a small amount of smoke in the front chamber 3. Similar results can be obtained in Figure 5B.

Figure 6 shows the situation when the fire source is at the 7th floor. 7A to 7C are schematic diagrams of simulations. As shown in Fig. 7A, the position of the fire door opening of the stairwell is changed, and the fixed air supply amount is 25000 m ³ /h. By adopting the method and system of the present invention, it is also possible to effectively prevent the flue gas from entering the stairwell 4. The location of the fire in the high-rise building is random. When the fire source 12 is located on the upper floor (7th floor), open two air outlets 11 (6th, 8th floor) near the fire source floor, the 10th The layer can be selectively opened. A large amount of airflow 13 enters the stairwell 4 through the air supply duct 10 from the open 2 or 3 air supply ports 11, and the effective pressure value of the smoke blocking near the fire floor in the stairwell is increased, and the fire source smoke can be effectively prevented from entering the stairwell 4. As shown in Fig. 7, the fixed air supply amount is 22500 m ³ /h, and it can be concluded that the number of open air supply ports is better to prevent smoke, which is consistent with the conclusions obtained in Figs. 4A and 4B.

The position of opening the air supply opening 11 also affects the smoke prevention effect of the positive pressure air supply system, and the opened air supply opening 11 is located below the fire floor to prevent smoke from failing; the open air supply opening is located above the fire floor, which basically prevents the smoke from entering the stairs. Room 4, but a large amount of flue gas exists in the front chamber 3; the open air supply port 11 is located near the fire floor, and the best smoke prevention effect can be achieved, as shown in Figs. 7B and 7C.

Figure 8 shows the situation when the fire source is at the 12th floor. When the fire source 12 is located at the highest floor (12 floors), and the number of fire door openings 7 of the stairwell 4 is increased, two consecutive air blowing ports 11 near the fire source floor are opened, and the third can be selectively opened and fixedly supplied with air. The amount is 27500 m ³ /h, and as shown in Fig. 9, the pressurized blower method of the present invention is still effective.

The specific embodiments of the present invention have been described in detail in the foregoing detailed description of the embodiments of the present invention. All modifications, equivalents, improvements, etc., made within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims

The utility model relates to a pressurized air supply and smoke blocking method for a stairwell of a high-rise building, wherein the high-rise building has a plurality of floors, and each floor is connected by a stairwell, and a plurality of air supply openings are arranged in the stairwell, and each air supply port is used for sending to the stairwell Wind, the method comprises the following steps:

S1. Detecting whether a fire occurs in each layer of the high-rise building;

S2. When it is detected in step S1 that a fire occurs in a certain layer of the high-rise building, only two or three air outlets closest to the floor are supplied with air.
The method according to claim 1, wherein the fire detector is used to detect the fire in the step S1.
The method for pressing a windshield of a high-rise building stairway according to claim 2,

In step S1, the fire detector generates a signal to a system controller when detecting the fire to report the layer number at which the fire occurs to the system controller;

In step S2, the system controller only sends air to two or three air outlets in the stairwell near the layer number indicated by the signal, and the other air outlets do not supply air.
The method according to claim 3, wherein each of the air supply openings is connected to a air supply duct, and the air supply duct is connected to a fan. When a specific air supply port is required to be blown, the steps are as follows. In S2, the system controller automatically controls to turn on the fan, and opens the air supply port that needs to supply air, and closes other air supply ports.
The method according to claim 4, wherein the opening and closing of the air supply openings are controlled by the system controller, and the air supply ports are normally opened to meet the ventilation requirements.
The method according to claim 4, wherein the fan is located at the top or bottom of the stairwell.
The method according to claim 4, wherein each of the stairwells has a front chamber adjacent thereto.
The utility model relates to a stairwell pressurized air supply and smoke blocking system applied to a high-rise building. The high-rise building has a plurality of layers, and each layer is connected by a stairwell, and a plurality of air supply openings are arranged in the stairwell, and each air supply port is used for The stairwell supplies air, and the system includes:

a fire detector disposed on each floor of the high-rise building for detecting whether a fire has occurred in each floor of the high-rise building;

The system controller, when the fire detector detects a fire in a certain layer of the high-rise building, only winds two or three air outlets closest to the floor.
A stairwell pressurized air blower system for use in a high-rise building as claimed in claim 8 wherein said fire detector generates a signal to a system controller when a fire is detected to report a fire to the system controller The layer number.
A stairwell pressurized air blower system for use in a high-rise building according to claim 9, wherein said system controller is configured to supply only the air supply port in the stairwell of the layer number indicated by said signal, and the other air supply port Do not send the wind.
The stairwell pressurized air supply and smoke blocking system for a high-rise building according to claim 10, wherein each of the air supply openings is connected to a air supply duct, and the air supply duct is connected to a fan, and the system controller is further used. The fan is controlled to be turned on when a specific air supply port is required to supply air.