Air and smoke exhaust system for long and narrow underground garage

Abstract

The invention discloses an air and smoke exhaust system for a long and narrow underground garage, which comprises a fan room, a first fan, a second fan, an outdoor air shaft and an air and smoke exhaust pipeline, and the first fan and the second fan are connected with the outdoor air shaft through air pipes; the air and smoke exhaust pipeline comprises smoke exhaust pipes, a first air pipe and a second air pipe, a three-way pipe I is fixedly connected to an air inlet of the first air pipe, and one smoke exhaust pipe is fixedly connected with a second port of the three-way pipe I; a three-way pipe II is fixedly connected to an air inlet of the second air pipe, the other smoke exhaust pipe is fixedly connected with a second port of the three-way pipe II, and the three-way pipe I and the three-way pipe II are connected through a connecting pipe. The narrow and long underground parking area is divided into the two smoke-proof subareas from the middle of the long edge of the narrow and long underground parking area, common air exhaust of the two smoke-proof subareas and independent smoke exhaust of each smoke-proof subarea are achieved by controlling opening and closing of the electric air valves, free switching of air exhaust and smoke exhaust of the underground garage can be achieved only through the double-speed fan and the single-speed fan, the structure is compact, and the cost is low. The fan room is small in occupied area, and initial investment is reduced.

Description

Technical Field

[0001] The present invention relates to the field of fire protection in underground garages, and particularly to an exhaust and smoke extraction system for a long and narrow underground garage. Background Art

[0002] According to the requirements of national codes, when mechanical smoke extraction is set in the parking area of an underground garage, smoke prevention zones should be demarcated to control the smoke within the space where the fire occurs and limit the spread of the smoke to other areas, so as to ensure the safe evacuation of personnel and fire fighting and rescue. To ensure the smoke extraction effect, the building area of a single smoke prevention zone shall not be greater than 2000 m 2 , and in some places, it is proposed that the long side length of the smoke prevention zone shall not be greater than 60 m or shall not be greater than 75 m .

[0003] Generally, an automatic fire extinguishing system is installed in an underground garage by taking a fire compartment as a unit, and the building area of each fire compartment shall not be greater than 4000 square meters. However, affected by terrain, equipment rooms, civil air defense projects, etc., there are usually long and narrow fire compartments with small areas, where the length > 75m and the building area ≤ 2000m 2 .

[0004] For a long and narrow fire compartment with a building area not greater than 2000 square meters, although the area meets the requirement of a single smoke prevention zone, due to its length > 75m, two smoke prevention zones still need to be demarcated. To meet the exhaust and smoke extraction requirements of each smoke prevention zone, the existing solution is to install a set of exhaust and smoke extraction system in each smoke prevention zone, but the exhaust volume design is often large, the fan power is large, increasing the investment cost and operating cost; there is also a solution to separate the smoke extraction and exhaust, that is, to install a set of smoke extraction system in each smoke prevention zone, and two smoke prevention zones share a set of exhaust system, that is, three fans are required to meet the exhaust and smoke extraction requirements of the long and narrow fire compartment, with high investment and large space occupied by the machine room. Summary of the Invention

[0005] In view of this, the present invention provides an exhaust and smoke extraction system for a long and narrow underground garage.

[0006] To achieve the above object, the present invention adopts the following technical solutions: The exhaust and smoke extraction system for a long and narrow underground garage of the present invention includes a fan room arranged in the underground garage, and further includes a first fan for exhaust and smoke extraction, a second fan for smoke extraction, an outdoor air shaft, and an exhaust and smoke extraction pipeline. The first fan is a two-speed fan or a variable-frequency fan, and the air outlets of the first fan and the second fan are connected to the outdoor air shaft through air ducts; The exhaust and smoke exhaust pipeline includes a smoke exhaust pipe suspended in each smoke prevention zone, a first air duct arranged at the air inlet of the first fan, and a second air duct arranged at the air inlet of the second fan. Each of the smoke exhaust pipes has a plurality of suction inlets arranged at intervals; a tee I is fixedly connected to the air inlet of the first air duct, and one of the smoke exhaust pipes is fixedly connected to the second port of the tee I; a tee II is fixedly connected to the air inlet of the second air duct, and the other smoke exhaust pipe is fixedly connected to the second port of the tee II. The third ports of the tee I and the tee II are connected by a connecting pipe installed with an electric air valve.

[0007] The beneficial effects are as follows: In the present invention, the long and narrow underground parking area is divided into two smoke prevention zones from the middle of its long side. By controlling the opening and closing of the electric air valve, the common exhaust of the two smoke prevention zones and the separate smoke exhaust of each smoke prevention zone are realized. Only a double-speed fan and a single-speed fan are needed to realize the free switching of exhaust and smoke exhaust in the underground garage. The structure is compact, the floor area of the fan room is small, and the initial investment is reduced; when operating, the low-speed mode can be adopted to realize the exhaust of the two smoke prevention zones, and the smoke exhaust mode is only started when a fire occurs, with low energy consumption, energy conservation and emission reduction.

[0008] Preferably, a first smoke exhaust fire damper and a muffler are arranged on the first air duct, a second smoke exhaust fire damper and a smoke exhaust valve are arranged on the second air duct; a normally closed smoke outlet is arranged on the smoke exhaust pipe close to the tee I; the first smoke exhaust fire damper and the first fan are interlocked (that is, the first smoke exhaust fire damper and the first fan are connected in series), and the second smoke exhaust fire damper and the second fan are interlocked (that is, the second smoke exhaust fire damper and the second fan are connected in series).

[0009] The beneficial effects are as follows: The self-closing temperature of the first smoke exhaust fire damper and the second smoke exhaust fire damper is 280°C. When the flue gas temperature exceeds 280°C, the smoke exhaust fire damper automatically closes and the corresponding fan stops smoke exhaust. On the one hand, it protects the fan, and on the other hand, it avoids the diffusion of flue gas with flames to other non-fire areas; the normally closed smoke outlet is remotely controlled. When a fire occurs, the normally closed smoke outlet opens, increasing the smoke outlet area and realizing large-volume smoke exhaust.

[0010] Preferably, the first fan is a double-speed centrifugal fan, and the second fan is a single-speed fan. During actual installation, the first fan is installed on the ground, and the second fan is hoisted. The structure is compact, and the floor area of the fan room is small.

[0011] Preferably, the exhaust pipe is formed by connecting multiple steel pipes with gradually decreasing sizes. During actual installation, suction inlets (i.e., exhaust and smoke exhaust openings) are provided on each steel pipe. The suction inlets are normally open and are arranged at intervals along the exhaust pipe to ensure more uniform air flow distribution. In addition, since the exhaust pipe can be connected to the first fan to achieve normal exhaust, that is, two smoke prevention zones jointly bear the exhaust volume, the cross-sectional size of the exhaust pipe is smaller than the conventional smoke pipe size in existing underground garages, saving steel consumption and reducing the initial project investment.

[0012] Compared with the prior art, the present invention divides a long and narrow underground parking area into two smoke prevention zones from the middle of its long side, and realizes the joint exhaust of the two smoke prevention zones and the separate smoke exhaust of each smoke prevention zone by controlling the opening and closing of the electric air valve. Only a double-speed fan and a single-speed fan are needed to achieve the free switching of exhaust and smoke exhaust in the underground garage. The structure is compact, the floor area of the fan room is small, and the initial investment is reduced; when operating, the low-speed mode can be used to achieve the exhaust of the two smoke prevention zones, and the smoke exhaust mode is only started when a fire occurs, with low energy consumption, energy conservation and emission reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is the installation schematic diagram (top view state) of the present invention in an underground garage.

[0014] Figure 2 is the schematic diagram of the present invention.

[0015] Figure 3 is the circuit principle block diagram of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0016] The following describes the embodiments of the present invention in detail with reference to the drawings. The embodiments are implemented on the premise of the technical solution of the present invention, and detailed implementation manners and specific operation processes are given. However, the protection scope of the present invention is not limited to the following embodiments.

[0017] It should be noted that in the description of the present invention, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0018] In the description of the present invention, unless otherwise clearly defined and limited, the terms "connected" and "connected" that may appear should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the communication inside two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood through specific situations.

[0019] As shown Figure 1-2 in the figure, the present invention provides an exhaust and smoke extraction system for a long and narrow underground garage, which includes a fan room 1 (located in the middle of the fire compartment) arranged in the underground garage, a first fan 2 for exhaust and smoke extraction, a second fan 4 for smoke extraction, an outdoor air shaft 6, and an exhaust and smoke extraction pipeline. The air outlets of the first fan 2 and the second fan 4 are connected to the outdoor air shaft 6 through air ducts to ensure the exhaust and smoke extraction of the underground garage; The exhaust and smoke extraction pipeline includes a smoke extraction pipe 7 suspended in each smoke prevention zone, a first air duct 3 arranged at the air inlet of the first fan 2, and a second air duct 5 arranged at the air inlet of the second fan 4. One end of the first air duct 3 is connected to the air inlet of the first fan 2, and a tee I is fixedly connected to the other end. The left smoke extraction pipe 7 is fixedly connected to the second port of the tee I; one end of the second air duct 5 is connected to the air inlet of the second fan 4, and a tee II is connected to the other end. The right smoke extraction pipe 7 is fixedly connected to the second port of the tee II; the third ports of the tee I and the tee II are connected through a connecting pipe installed with an electric air valve 9; Among them, a plurality of suction inlets 8 (i.e., exhaust and smoke extraction openings for smoke extraction and exhaust) are evenly distributed on each smoke extraction pipe 7; the first fan 2 adopts a double-speed centrifugal fan, which has a high-speed air volume and a low-speed air volume. Its high-speed air volume is used for smoke extraction, and its low-speed air volume is used for exhaust; the second fan 4 adopts a single-speed smoke extraction fan, and its air volume is the same as the high-speed air volume of the first fan 2 to meet the high-speed smoke extraction requirements during smoke extraction.

[0020] During operation, the electric air valve 9 is in the normally open state. The first air duct 3 serves as the main air duct, and the two smoke extraction pipes 7 serve as branch air ducts to realize the connection between the two smoke extraction pipes 7 and the first fan 2, ensuring the normal exhaust of the two smoke prevention zones during non-fire; when a fire occurs in the parking area, the electric air valve 9 is closed, the connection between the two smoke extraction pipes 7 is disconnected, so that the two smoke extraction pipes 7 and the two fans are connected one by one, and then two independent smoke extraction systems are formed. Starting the fan corresponding to the fire area can realize the smoke extraction of this area and improve the smoke extraction efficiency.

[0021] The present invention integrates exhaust and smoke extraction. By using a single separate fan and a double-speed fan, the exhaust of two smoke prevention zones and the separate control of each smoke prevention zone can be realized. It can both exhaust and extract smoke, and is especially suitable for narrow underground garages; the system of the present invention is simple, reduces the initial investment cost, and has low operation energy consumption.

[0022] During actual installation, the exhaust pipe 7 is formed by connecting multiple steel pipes (which can be stainless steel pipes or galvanized steel pipes) with gradually decreasing cross-sectional dimensions. Each steel pipe has at least one suction port 8, and the suction port 8 is a normally open port. A normally closed exhaust port 10 (an electric exhaust port, remotely controlled) is also provided at the near-fan end of one of the exhaust pipes 7 and is opened during exhaust. In the present invention, since the two exhaust pipes 7 share the system exhaust air volume during exhaust, the cross-sectional dimension of the exhaust pipe 7 can be smaller than the conventional design dimension, reducing the initial investment.

[0023] During actual installation, a first smoke exhaust fire damper 11 and a muffler 12 (to reduce exhaust noise) are provided on the first air duct 3; a second smoke exhaust fire damper 13 and a smoke exhaust valve 14 are provided on the second air duct 5. Both the first smoke exhaust fire damper 11 and the second smoke exhaust fire damper 13 have self-closing functions. When the flue gas temperature exceeds its set temperature (generally considered that the flue gas will carry flames when the temperature exceeds 280°C, so the self-closing temperature of the two smoke exhaust fire dampers is preferably 280°C), the first smoke exhaust fire damper 11 and the second smoke exhaust fire damper 13 automatically close. The first smoke exhaust fire damper 11 is interlocked with the first fan 2 (i.e., the first smoke exhaust fire damper 11 and the first fan are in series), and the second smoke exhaust fire damper 13 is interlocked with the second fan 4 (i.e., the second smoke exhaust fire damper 13 and the second fan are in series). When the first smoke exhaust fire damper 11 or the second smoke exhaust fire damper 13 self-closes, the corresponding fan loses power, avoiding the fan catching fire due to excessive flue gas temperature and also preventing the fire from spreading to non-fire areas through the smoke exhaust system.

[0024] During actual installation, the normally closed exhaust port 10, the first smoke exhaust fire damper 11, the second smoke exhaust fire damper 13, and the smoke exhaust valve 14 are preferably electric control valves. The normally closed exhaust port 10, the first smoke exhaust fire damper 11, the second smoke exhaust fire damper 13, the smoke exhaust valve 14, and the electric air valve 9 are all communicatively connected to the control system in the fire control room. The controlled ends of the first fan 2 and the second fan 4 are communicatively connected to the control system. See Figure 3 for details. When a fire occurs, the control system controls the electric air valve 9 to close to form two smoke exhaust systems. The control system issues a smoke exhaust command for the corresponding smoke exhaust system in the fire area according to the fire area, starts the fan (or adjusts the fan to high-speed air volume), and opens the corresponding valve to achieve rapid smoke exhaust in the area. Of course, during actual installation, manual switches corresponding to the normally closed exhaust port 10 and the smoke exhaust valve 14 can be installed in the fan room 1. When the inspection personnel discover a fire, they can also manually open it, and after manual opening, the linkage signal is transmitted to the control system to achieve zoned smoke exhaust to meet the smoke exhaust requirements of each smoke prevention zone.

[0025] Specifically, taking a narrow underground garage as an example, the net height of the parking area in the fire compartment of the underground garage is 4m, and the building area of the parking area is 1950m 2, the long side of the parking area is 108 m. By adopting the technical solution of the present invention, a smoke baffle is constructed at the middle position (or near the center position) of the long side of the parking area, and then the fire compartment is divided into two smoke compartments with a length of 54 m each; Considering the air leakage and the deviation of the fan itself, the designed smoke exhaust volume of each smoke compartment is 37800 m 3 / h, and the total designed exhaust air volume of the parking area in this fire compartment is 25600 m 3 / h. A total of one fan room 1 is set up, and a first fan 2 is installed on the ground. Its high-speed air volume is 37800 m 3 / h, and the low-speed air volume is 25600 m 3 / h; A second fan 4 is hoisted in the fan room 1, and the air volume is 37800 m 3 / h. A smoke exhaust pipe 7 is hoisted in each smoke compartment. According to the solution of the present invention, the two fans are respectively connected to the smoke exhaust pipe 7, and the corresponding smoke prevention and fire valves, smoke valves 14 and electric air valves 9 are installed correspondingly, and the installation can be completed. During operation, the electric air valve 9 is an open valve, so that the two smoke exhaust pipes 7 are both connected to the first air duct 3, and the first fan 2 is used for low-speed air extraction to realize the normal exhaust of the entire parking area; when a fire occurs in any one of the smoke compartments, the electric air valve 9 is closed to form two independent smoke exhaust systems; the fan in the smoke compartment where the fire is located is started for high-speed smoke exhaust to minimize the fire loss as much as possible. When the smoke temperature exceeds 280 °C, the smoke prevention and fire valve cuts off and the corresponding fan is powered off to prevent the spread of the fire.

[0026] Finally, it should be emphasized that the above is only the preferred embodiment of the present invention and is not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still make modifications to the technical solutions described in the foregoing embodiments without creative labor, or make equivalent replacements for some of the technical features. Therefore, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An exhaust and smoke exhaust system for a long and narrow underground garage, comprising a fan room arranged in the underground garage, characterized in that: It also includes a first fan for exhausting air and smoke, a second fan for exhausting smoke, an outdoor air shaft and an air and smoke exhaust pipeline, wherein the first fan is a two-speed fan or a variable frequency fan, and the air outlets of the first fan and the second fan are connected to the outdoor air shaft through air ducts; The air and smoke exhaust pipeline includes a smoke exhaust pipe suspended in each smoke proof partition, a first air duct arranged at the air inlet of the first fan, and a second air duct arranged at the air inlet of the second fan, each of the smoke exhaust pipes has a plurality of suction ports arranged at intervals; a three-way pipe I is fixedly connected to the air inlet of the first air duct, and one of the smoke exhaust pipes is fixedly connected to the second port of the three-way pipe I; a three-way pipe II is fixedly connected to the air inlet of the second air duct, and the other smoke exhaust pipe is fixedly connected to the second port of the three-way pipe II, and the third ports of the three-way pipe I and the three-way pipe II are connected by a connecting pipe equipped with an electric air valve.

2. The ventilation and smoke exhaust system for a narrow and long underground garage according to claim 1 is characterized in that: The first air duct is provided with a first smoke exhaust fire damper and a muffler, and the second air duct is provided with a second smoke exhaust fire damper and a smoke exhaust valve; the smoke exhaust duct close to the three-way pipe I is provided with a normally closed smoke exhaust port; the first smoke exhaust fire damper is interlocked with the first fan, and the second smoke exhaust fire damper is interlocked with the second fan.

3. The ventilation and smoke exhaust system for a narrow and long underground garage according to claim 1 is characterized in that: The first fan is a dual-speed centrifugal fan, and the second fan is a single-speed fan.

4. The ventilation and smoke exhaust system for a narrow and long underground garage according to claim 1 is characterized in that: The smoke exhaust pipe is formed by connecting a plurality of steel pipes with successively smaller cross-sectional dimensions.

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