CN107899167A - A kind of pre-heated fine water mist fire-extinguishing system and water mists nozzle - Google Patents

Abstract

The invention specifically relates to a preheating type fine water mist fire extinguishing system and a fine water atomization nozzle, which solves the problem that the existing fire extinguishing system cannot form an effective suffocation environment for a fire with a small calorific value, resulting in difficulty in extinguishing a fire with fine water mist. The water mist fire extinguishing system includes fire alarm equipment, control devices and fire extinguishing system; the fire extinguishing system includes filters, pump sets, heat exchangers and fine water atomizing nozzles connected through pipelines in sequence; the heat exchanger is exchanged by the burner Heat, the burner is connected to the fine water atomization nozzle through the induced draft fan; a signal feedback device is installed on the pipeline between the heat exchanger and the fine water atomization nozzle, and the signal feedback device is connected to the control device through the control line; the fine water atomization The nozzle is arranged in the protection area, and the flame detection device is arranged in the protection area, and the flame detection device is connected with the fire alarm equipment. The fine water mist fire extinguishing system and nozzles of the present invention can effectively extinguish fires with relatively small calorific value, such as initial small fires, Class A fires, and smoldering fires.

Description

A preheating type fine water mist fire extinguishing system and fine water atomization nozzle

technical field

The invention relates to the field of fire engineering, in particular to a preheating type fine water mist fire extinguishing system and a fine water atomization nozzle.

Background technique

Haloalkane series fire extinguishing agents have been widely used as high-efficiency and low-toxicity fire extinguishing agents, but studies have found that they have a strong destructive effect on the atmospheric ozone layer, so haloalkane is gradually banned from use internationally. Compared with the traditional water sprinkler system, the water mist system has the advantages of high fire extinguishing efficiency, small water consumption, and low water damage loss, and is recognized as one of the most effective technologies for replacing halon fire extinguishing. One of the main mechanisms of water mist fire extinguishing is suffocation. The water mist has a small diameter and a large specific surface area. After absorbing heat, it quickly vaporizes and turns into water vapor. The volume increases by more than a thousand times. On the one hand, the water vapor dilutes the original combustion area. On the other hand, it forms a shield around the flame to prevent new air from entering the combustion area. Due to the lack of oxygen, the combustion will be inhibited or interrupted. The suffocation effect of the fine water mist system depends on whether it can quickly generate a large amount of water vapor and Cover the surface of the flame.

For fires with low calorific value such as initial small fires, Class A fires, and smoldering fires, the amount of water vapor generated by the heat of the flame is very small, and the oxygen consumption of these small fires is low, and the water vapor cannot form an effective suffocation environment, resulting in fine air. It is difficult to extinguish the fire with water mist.

Contents of the invention

The purpose of the present invention is to solve the problem that the existing fire extinguishing system cannot form an effective suffocation environment for fires with small calorific value, resulting in difficulty in extinguishing fires with fine water mist, and provide a set that can effectively extinguish initial small fires, Class A fires, smoldering fires, etc. The advanced water mist fire extinguishing system and fine water atomizing nozzles can also obtain higher fire extinguishing performance in colder environments.

The technical scheme that the present invention solves the above problems is:

A preheating type water mist fire extinguishing system, including fire alarm equipment, a control device and a fire extinguishing system, the control device is used to control the fire alarm equipment and fire extinguishing system; the fire extinguishing system includes filters connected sequentially through pipelines , a pump unit, a heat exchanger and a fine water atomization nozzle; A signal feedback device is arranged on the pipeline between the atomizing nozzles, and the signal feedback device is connected to the control device through a control line; the fine water atomizing nozzle is arranged in a protected area, and a flame detection device is arranged in the protected area, The flame detection device is connected to the fire alarm equipment; the fine water atomization nozzle includes a nozzle upper base, a nozzle lower base, a nozzle outer core and a nozzle inner core; the nozzle upper base is fixedly arranged under the nozzle Above the base, the inside of the base on the nozzle is provided with a fire extinguishing port, a second atomization chamber and an inner cavity connected in sequence, the second atomization chamber is an inverted cone hole structure, and the side of the base on the nozzle is provided with There is a smoke inlet channel connected with the inner cavity, and a water inlet channel is provided on the lower base of the nozzle; the outer core of the nozzle is a stepped structure, which is fixedly arranged inside the upper base of the nozzle and the lower base of the nozzle, so that A plurality of swirl grooves are arranged on the outer peripheral surface of the step at the upper end of the outer core of the nozzle, and a first atomization chamber communicating with the second atomization chamber is arranged inside the step, and the first atomization chamber is a tapered hole structure. The side of the nozzle outer core is provided with a plurality of swirl holes communicating with the smoke inlet passage of the upper base of the nozzle; the nozzle inner core is arranged inside the nozzle outer core, and its lower end is fixedly connected with the nozzle outer core, and the outer peripheral surface of the upper end There is a gap between the inner peripheral surface of the outer core of the nozzle, and the inner core of the nozzle is provided with a flow hole communicating with the water inlet channel and the first atomization chamber, and the cross-sectional area of the flow hole along the water flow direction gradually increases. Narrowed down with diverging angles at the exit.

Further, the upper base of the nozzle and the lower base of the nozzle, the outer core of the nozzle and the inner core of the nozzle, the lower base of the nozzle and the outer core of the nozzle are all fixedly connected by threads.

Further, the heat exchanger is arranged in a heating furnace, and the heating furnace heats the liquid in the furnace through a burner.

Further, the outlet end of the pump set is provided with a safety valve.

Further, a pressure gauge is provided on the pipeline between the heat exchanger and the fine water atomizing nozzle.

Further, the flue gas outlet pipeline of the burner is provided with a temperature monitoring thermocouple.

Further, a solenoid valve and a manual valve are also arranged between the heat exchanger and the fine water atomizing nozzle, and the solenoid valve is connected to the fire alarm equipment through a control line.

Further, the fire alarm equipment is provided with a fire alarm button, a fire alarm controller and a fire alarm device.

At the same time, the present invention also provides a fine water atomization nozzle, comprising a nozzle upper base, a nozzle lower base, a nozzle outer core and a nozzle inner core; the nozzle upper base is fixedly arranged on the nozzle lower base Above, the inside of the nozzle upper base is provided with a fire extinguishing port, a second atomization chamber and an inner cavity connected in sequence, the second atomization chamber is an inverted cone hole structure, and the side of the nozzle upper base is provided with a A smoke inlet channel connected to the cavity, and a water inlet channel is provided on the lower base of the nozzle; the outer core of the nozzle is a stepped structure, fixedly arranged inside the upper base of the nozzle and the lower base of the nozzle, and the outer core of the nozzle A plurality of swirl grooves are arranged on the outer peripheral surface of the step at the upper end of the core body, and a first atomization chamber communicated with the second atomization chamber is arranged inside the step, the first atomization chamber has a cone hole structure, and the outer core of the nozzle The side of the body is provided with a plurality of swirl holes communicating with the smoke inlet passage of the upper base of the nozzle; the inner core of the nozzle is arranged inside the outer core of the nozzle, its lower end is fixedly connected with the outer core of the nozzle, and the outer peripheral surface of the upper end is connected with the outer surface of the nozzle. There is a gap between the inner peripheral surfaces of the core, and the inner core of the nozzle is provided with a flow hole communicating with the water inlet channel and the first atomization chamber, and the cross-sectional area of the flow hole is gradually reduced along the water flow direction, and There is an expansion angle at the exit.

Further, the upper base of the nozzle and the lower base of the nozzle, the outer core of the nozzle and the inner core of the nozzle, the lower base of the nozzle and the outer core of the nozzle are all fixedly connected by threads.

The advantages of the present invention are:

1. The fine water mist fire extinguishing system of the present invention can effectively extinguish fires with small calorific value such as initial small fires, Class A fires, and smoldering fires. The system can also obtain higher fire extinguishing performance in a colder environment, reducing the Risk of damage to life and property due to fire.

2. The system of the present invention introduces a combustion heating device. The burner is used to preheat the incoming water, and the normal temperature water is promoted to high temperature water to participate in fire extinguishing, which improves the efficiency of water mist fire extinguishing. Since the burner is used to preheat the incoming water , the combustion efficiency of the burner is high, and the main products after combustion of gas or fuel oil are CO ₂ , H ₂ O and N ₂ , which are ideal gas fire extinguishing agents. Compared with the agent, it can further reduce the oxygen content in the fire extinguishing area and improve the suffocation fire extinguishing effect.

3. The preheated water of the present invention enters the atomizing nozzle from the water inlet channel of the nozzle lower base, the atomizer (smoke) enters the atomizing nozzle from the side opening of the upper base of the nozzle, and the preheated water passes through the lower base of the nozzle. The seat enters the inner core of the nozzle, the flow channel of the inner core of the nozzle gradually narrows, the preheated water will be sprayed into the first atomization chamber at high speed, and the atomization will be carried out under the action of the high-speed jet and the rotating atomizer, and a part of the atomizer will pass through The small hole opened on the outer core of the nozzle enters the gap between the inner and outer core of the nozzle in a tangential swirling manner, and then mixes with water in the first atomization chamber, and the other part of the atomizer passes through the hole at the end of the outer core of the nozzle. The swirl tank enters the second atomization chamber in the form of axial swirl, and mixes again with the mixture discharged from the first atomization chamber to further refine the atomized droplets. After mixed and atomized by the spray nozzle, it is sprayed towards the fire source at high speed. Due to the suffocation of water vapor and smoke, the fire source will be quickly extinguished, and the fire extinguishing efficiency will be further improved.

4. The system of the present invention can replace the existing haloalkane fire extinguishing system, contribute to the protection of the atmospheric ozone layer, and is environmentally friendly and energy-saving.

Description of drawings

Fig. 1 is the figure of the preheating type water mist fire extinguishing system of the embodiment of the present invention;

Fig. 2 is a structural diagram of a fine water mist nozzle according to an embodiment of the present invention;

Fig. 3 is A-A sectional view of Fig. 2;

Fig. 4 is the B-B sectional view of Fig. 2;

Fig. 5 is a structural diagram of the base on the nozzle of the embodiment of the present invention;

Fig. 6 is a structural diagram of the outer core of the fine water mist nozzle according to the embodiment of the present invention.

Reference signs: 1-fire alarm equipment, 2-induced fan, 3-heating furnace, 4-heat exchanger, 5-burner, 6-pump set, 7-filter, 8-control device, 9-safety Valve, 10-pressure gauge, 11-signal feedback device, 12-solenoid valve, 13-fine water atomization nozzle, 14-flame detection device, 15-temperature monitoring thermocouple, 16-manual valve, 17-fire alarm button, 18-Fire alarm controller, 19-Fire alarm device, 131-Nozzle upper base, 132-Nozzle lower base, 133-Nozzle outer core, 134-Nozzle inner core, 1311-Fire extinguisher, 1312-Second Atomization chamber, 1313-inner cavity, 1314-smoke inlet channel, 1321-water inlet channel, 1331-swirl tank, 1332-first atomization chamber, 1333-swirl hole, 1341-flow hole.

Detailed ways

The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings.

A kind of preheating type water mist fire extinguishing system as shown in Fig. 1 to Fig. 6, comprises fire alarm equipment 1, control device 8 and fire extinguishing system, and control device 8 is used for controlling fire alarm equipment 1 and fire extinguishing system; Fire extinguishing system comprises The filter 7, the pump group 6, the heat exchanger 4 and the fine water atomization nozzle 13 connected by the pipeline in sequence; Heat the heat exchanger 4 to exchange heat or flush the heat exchanger 4 with the high-temperature gas and smoke generated by the burner 5 to exchange heat. The burner 5 is connected to the fine water atomization nozzle 13 through the induced draft fan 2; the heat exchanger 4 and the fine water atomizing nozzle 13 are provided with a signal feedback device 11 on the pipeline, and the signal feedback device 11 is connected with the control device 8 through a control line; the fine water atomizing nozzle 13 is arranged in a protected area, and a The flame detection device 14 is connected with the fire alarm device 1 . The fire alarm device 1 is provided with a fire alarm button 17, a fire alarm controller 18 and a fire alarm device 19, a safety valve 9 is provided at the outlet end of the pump unit 6, and the pipe between the heat exchanger 4 and the fine water atomizing nozzle 13 A pressure gauge 10, a solenoid valve 12 and a manual valve 16 are arranged on the road, and the solenoid valve 12 is connected with the fire alarm equipment 1 through a control line.

The flame detection device 4 is devices such as optical detection (including ultraviolet, infrared) and ion probe detection. The safety valve is a special valve whose opening and closing parts are in a normally closed state under the action of external force. When the medium pressure in the equipment or pipeline rises above the specified value, it discharges the medium to the outside of the system to prevent the medium pressure in the pipeline or equipment from exceeding the specified value. , Specifically, the stainless steel micro-opening safety valve A41W type can be used.

The fine water atomizing nozzle 13 of the above-mentioned system comprises a nozzle upper base 131, a nozzle lower base 132, a nozzle outer core 133 and a nozzle inner core 134; the nozzle upper base 131 is fixedly arranged above the nozzle lower base 132, The inside of the nozzle upper base 131 is provided with a fire extinguishing port 1311, a second atomization chamber 1312 and an inner cavity 1313 connected in sequence. The second atomization chamber 1312 has an inverted cone hole structure. The smoke inlet channel 1314 connected to the cavity 1313, the water inlet channel 1321 is provided on the nozzle lower base 132; the nozzle outer core 133 is a stepped structure, fixedly arranged inside the nozzle upper base 131 and the nozzle lower base 132, the nozzle A plurality of swirl grooves 1331 are provided on the outer peripheral surface of the upper step of the outer core 133, and a first atomization chamber 1332 communicating with the second atomization chamber 1312 is provided inside the step. The first atomization chamber 1332 has a tapered hole structure, and the nozzle The side of the outer core 133 is provided with a plurality of swirl holes 1333 communicating with the smoke inlet channel 1314 on the nozzle upper base; the nozzle inner core 134 is arranged inside the nozzle outer core 133, and its lower end is fixedly connected with the nozzle outer core 133, There is a gap between the outer peripheral surface of the upper end and the inner peripheral surface of the nozzle outer core 133, and the nozzle inner core 134 is provided with a flow hole 1341 communicating with the water inlet channel 1321 and the first atomization chamber 1332, and the flow hole 1341 is along the The cross-sectional area of the channel in the direction of water flow is gradually reduced, and an expansion angle is provided at the outlet. The nozzle upper base 131 and the nozzle lower base 132 , the nozzle outer core 133 and the nozzle inner core 134 , the nozzle lower base 132 and the nozzle outer core 133 are fixedly connected by threads.

Since the flue gas generated after combustion in the system contains a large amount of H ₂ O, the temperature of the flue gas should not be too low, otherwise condensation will occur in the pipeline, so a temperature monitoring thermoelectric unit is installed on the flue gas outlet pipeline of the burner 5 Even 15, monitor the flue gas temperature in the pipeline in real time, and maintain the flue gas temperature at 120-160°C by adjusting the fuel input of the burner 5.

The burner 5, heat exchanger 4 and heating furnace 3 are introduced into the fine water mist fire extinguishing system, and the incoming water is preheated through the above equipment, and the water participating in the atomization is raised from normal temperature to a higher temperature, so as to improve the fine mist fire extinguishing effect. The efficiency of the system can effectively extinguish the initial small fire, Class A fire, smoldering fire, etc. The flue gas after burning fuel oil or gas through the burner 5 is used as the atomizing medium. Since the main components of the flue gas are H2O, CO2 and N2, and the oxygen content is extremely low, using the flue gas as the atomizer can further reduce the Due to the high temperature of flue gas, it can also promote the generation of more water vapor and improve the fire extinguishing performance of fine water mist. When the flame detection device 14 finds that there is a fire in the protected area, it starts the pump set, the induced draft fan 2 and the burner 5 sequentially within a short period of time (15s), and quickly sprays fine water mist into the protected area to realize fast and effective fire extinguishing , the system can replace the existing haloalkane fire extinguishing system.

As shown in Figures 2 to 6, since the waterway in the system is a medium-high pressure system and the atomizer is a low-pressure system, a matching atomization nozzle is set up. The nozzle is a two-stage atomization structure, that is, the atomizer and water Two encounters, the first atomizer passes through the tangential swirl hole 1333 to form a high-speed swirling airflow, and then meets water; the second atomization agent passes through the axial swirl groove 1331 to form a high-speed swirling airflow, and then meets water.

The fine water atomizing nozzle 13 comprises a nozzle upper base 131, a nozzle lower base 132, a nozzle outer core 133 and a nozzle inner core 134; the nozzle upper base 131 is fixedly arranged above the nozzle lower base 132 by threads, and the nozzle The inside of the upper base 131 is provided with a fire extinguishing port 1311, a second atomization chamber 1312 and an inner cavity 1313 connected in sequence. The second atomization chamber 1312 has an inverted cone hole structure. The smoke inlet channel 1314 connected with the body 1313, the water inlet channel 1321 is provided on the nozzle lower base 132; the nozzle outer core body 133 is a stepped structure, and is fixedly arranged inside the nozzle upper base 131 and the nozzle lower base 132 by threads, A plurality of swirl grooves 1331 are provided on the outer peripheral surface of the upper step of the nozzle outer core 133, and a first atomization chamber 1332 communicating with the second atomization chamber 1312 is provided inside the step, and the first atomization chamber 1332 has a tapered hole structure. The side of the nozzle outer core 133 is provided with a plurality of swirl holes 1333 communicating with the smoke inlet channel 1314 of the nozzle upper base 131; the nozzle inner core 134 is arranged inside the nozzle outer core 133, and its lower end passes through the nozzle outer core 133 The thread is fixedly connected, and there is a gap between the outer peripheral surface of the upper end and the inner peripheral surface of the nozzle outer core body 133, and the nozzle inner core body 134 is provided with a flow hole 1341 in communication with the water inlet channel 1321 and the first atomization chamber 1332. The channel cross-sectional area of the orifice 1341 decreases gradually along the water flow direction, and an expansion angle is provided at the outlet.

The four parts of the fine water atomizing nozzle 13 are connected by threads, and the nozzle is a detachable structure, which is beneficial to the manufacture, processing and assembly of each part of the nozzle, as well as the maintenance and cleaning in the later stage. When one of the parts is damaged, it can also be replaced with spare parts , without replacing the entire nozzle, saving costs.

Water enters from the inner core body 134 of the nozzle. The inner core body 134 of the nozzle has a variable diameter structure, and the cross-sectional area of the channel gradually decreases along the water flow direction. In order to obtain a better atomization effect, there is a small expansion angle at the outlet. The nozzle inner core body 134 and the nozzle outer core body 133 enclose an expanding first atomization chamber 1332, and the nozzle outer core body 133 and the nozzle upper base 131 enclose a shrinking second atomization chamber 1312, forming two-stage mist The atomization structure, the atomizer forms a tangential swirl flow through the swirl hole 1333 of the nozzle outer core 133 in the gap between the inner and outer cores of the nozzle; forms an axial swirl flow through the swirl groove 1331 of the nozzle outer core 133, and passes through After two atomizations, the air-water mixture is sprayed from the nozzle to the fire source at high speed.

Working principle of the system: The saturated partial pressure of water vapor increases with the increase of the ambient temperature. For example, at 10°C, water vapor accounts for 1.21% of the entire humid air volume, and when the temperature is 80°C, the water vapor accounts for the entire wet air volume. 47.1%. By calculating the water vapor under saturated conditions, the oxygen concentration is 20.7% at 10°C, and it is reduced to 11.1% at 80°C. It can be seen that when the ambient temperature rises, the fire extinguishing efficiency of fine water mist can be effectively improved, although it is sprayed into the flame. Most of the water mist above will evaporate, but when the water vapor moves to other areas due to buoyancy, due to the low ambient temperature, it will condense again into water and fall to the ground, reducing the dilution effect of water vapor on oxygen. It can be seen that through preheating Raising the water temperature with water is an effective means to solve the difficult problem of extinguishing initial small fires, Class A fires and smoldering fires with fine water mist. Combustion heating is the most direct way to obtain hot water, and the integral burner 5 technology that integrates ignition, combustion, and flame detection has been very mature. Combustion method to obtain hot water has the advantages of high efficiency and economy. After the burner 5 effectively organizes the combustion, its products are mainly CO ₂ , H ₂ O and N ₂ , which are ideal gaseous fire extinguishing agents, and the use of flue gas as an atomizing agent can further improve the fire extinguishing efficiency of fine water mist.

The working process of the system: when the flame detection device 14 detects a fire signal in the protected area, it transmits the signal to the fire alarm device 1, and the fire alarm device 1 transmits the fire signal to the control device 8 while emitting sound and light alarms , the control device 8 sends a signal to start the pump group 6, and the pump group 6 starts; at the same time, the blower of the burner 5 and the induced draft fan 2 start, and after the heating furnace 3 is purged for 10 seconds, the burner 5 automatically ignites and ignites the fuel, and the pump group After starting, the water first enters the filter 7 to remove impurities, then enters the pump group, and is sent to the heat exchanger 4 after being pressurized. In the water atomizing nozzle 13 , gas or fuel is combusted by the burner 5 to generate flue gas, which is combusted by the induced draft fan 2 and enters the fine water atomizing nozzle 13 .

The preheated water enters the atomizing nozzle through the water inlet channel 1321 of the nozzle lower base 132, and the atomizing agent smoke enters the atomizing nozzle through the side opening of the nozzle upper base 131. The preheated water enters the nozzle inner core 134 through the water inlet channel 1321, and the flow channel in the nozzle inner core 134 gradually narrows, and the preheated water will be sprayed into the first atomization chamber 1332 at a high speed, and the high speed jet and the rotating atomizer A part of the atomizing agent passes through the small hole opened on the nozzle outer core 133, and enters the gap between the nozzle inner and outer cores in a tangential swirling manner, and then is mixed with water in the first atomization chamber 1332. Mixing; another part of the atomizer passes through the swirl groove 1331 at the end of the nozzle outer core 133, enters the second atomization chamber 1312 in an axial swirl manner, and mixes again with the mixture discharged from the first atomization chamber 1332, The atomized liquid droplets are further refined. After the preheated water and smoke are mixed and atomized by the atomizing nozzle, they are sprayed towards the fire source at high speed. Due to the suffocation of water vapor and smoke, the fire source will be quickly extinguished. .

Claims (10)

1. A preheating type water mist fire extinguishing system is characterized in that: it comprises a fire alarm device (1), a control device (8) and a fire extinguishing system, and the control device (8) is used to control the fire alarm device (1) and fire suppression systems; The fire extinguishing system includes a filter (7), a pump group (6), a heat exchanger (4) and a fine water atomizing nozzle (13) connected through pipelines in sequence; The burner (5) performs heat exchange, and the burner (5) is connected with the fine water atomizing nozzle (13) through the induced draft fan (2); the connection between the heat exchanger (4) and the fine water atomizing nozzle (13) A signal feedback device (11) is arranged on the pipeline between, and the signal feedback device (11) is connected with the control device (8) through a control line; the fine water atomization nozzle (13) is arranged in a protected area, and the A flame detection device (14) is provided in the protected area, and the flame detection device (14) is connected to the fire alarm device (1); The fine water atomization nozzle (13) includes a nozzle upper base (131), a nozzle lower base (132), a nozzle outer core (133) and a nozzle inner core (134); The nozzle upper base (131) is fixedly arranged above the nozzle lower base (132), and the interior of the nozzle upper base (131) is provided with a fire extinguishing port (1311), a second atomization chamber (1312) and The inner cavity (1313), the second atomization chamber (1312) is an inverted cone hole structure, and the side of the upper base (131) of the nozzle is provided with a smoke inlet passage (1314) communicating with the inner cavity (1313) ), the nozzle lower base (132) is provided with a water inlet channel (1321); The nozzle outer core (133) has a stepped structure, and is fixedly arranged inside the nozzle upper base (131) and the nozzle lower base (132). A plurality of swirl grooves (1331), the first atomization chamber (1332) communicating with the second atomization chamber (1312) is provided inside the step, the first atomization chamber (1332) is a cone hole structure, the The side of the nozzle outer core (133) is provided with a plurality of swirl holes (1333) communicating with the smoke inlet channel (1314) of the upper base of the nozzle; The nozzle inner core (134) is arranged inside the nozzle outer core (133), its lower end is fixedly connected with the nozzle outer core (133), and the outer peripheral surface of the upper end is arranged between the inner peripheral surface of the nozzle outer core (133). There is a gap, the inner core body (134) of the nozzle is provided with a flow hole (1341) communicating with the water inlet channel (1321) and the first atomization chamber (1332), and the flow hole (1341) is along the water flow The cross-sectional area of the direction channel is gradually reduced, and an expansion angle is provided at the exit. 2. The preheating type water mist fire extinguishing system according to claim 1, characterized in that: the nozzle upper base (131) and the nozzle lower base (132), the nozzle outer core (133) and the nozzle inner The core body (134), the nozzle lower base (132) and the nozzle outer core body (133) are all fixedly connected by threads. 3. The preheating type water mist fire extinguishing system according to claim 2, characterized in that: the heat exchanger (4) is arranged in the heating furnace (3), and the heating furnace (3) passes through the burner ( 5) Heating the liquid in the furnace. 4. The preheated water mist fire extinguishing system according to claim 1, 2 or 3, characterized in that: a safety valve (9) is provided at the outlet end of the pump set (6). 5. The preheating type water mist fire extinguishing system according to claim 4, characterized in that: a pressure gauge (10) is arranged on the pipeline between the heat exchanger (4) and the water atomization nozzle (13) ). 6. The preheating type water mist fire extinguishing system according to claim 5, characterized in that: a temperature monitoring thermocouple (15) is arranged on the flue gas outlet pipeline of the burner (5). 7. The preheating type water mist fire extinguishing system according to claim 6, characterized in that: a solenoid valve (12) and a A manual valve (16), the electromagnetic valve (12) is connected with the fire alarm equipment (1) through a control line. 8. The preheating type water mist fire extinguishing system according to claim 7, characterized in that: the fire alarm device (1) is provided with a fire alarm button (17), a fire alarm controller (18) and a fire alarm device (19). 9. A fine water atomization nozzle, characterized in that: it comprises a nozzle upper base (131), a nozzle lower base (132), a nozzle outer core (133) and a nozzle inner core (134); The nozzle upper base (131) is fixedly arranged above the nozzle lower base (132), and the interior of the nozzle upper base (131) is provided with a fire extinguishing port (1311), a second atomization chamber (1312) and The inner cavity (1313), the second atomization chamber (1312) is an inverted cone hole structure, and the side of the upper base (131) of the nozzle is provided with a smoke inlet passage (1314) communicating with the inner cavity (1313) ), the nozzle lower base (132) is provided with a water inlet channel (1321); The nozzle outer core (133) has a stepped structure, and is fixedly arranged inside the nozzle upper base (131) and the nozzle lower base (132). A plurality of swirl grooves (1331), the first atomization chamber (1332) communicating with the second atomization chamber (1312) is provided inside the step, the first atomization chamber (1332) is a cone hole structure, the The side of the nozzle outer core (133) is provided with a plurality of swirl holes (1333) communicating with the smoke inlet passage (1314) of the nozzle upper base (131); The nozzle inner core (134) is arranged inside the nozzle outer core (133), its lower end is fixedly connected with the nozzle outer core (133), and the outer peripheral surface of the upper end is arranged between the inner peripheral surface of the nozzle outer core (133). There is a gap, the inner core body (134) of the nozzle is provided with a flow hole (1341) communicating with the water inlet channel (1321) and the first atomization chamber (1332), and the flow hole (1341) is along the water flow The cross-sectional area of the direction channel is gradually reduced, and an expansion angle is provided at the exit. 10. The fine water atomization nozzle according to claim 9, characterized in that: the nozzle upper base (131) and the nozzle lower base (132), the nozzle outer core (133) and the nozzle inner core ( 134), the nozzle lower base (132) and the nozzle outer core (133) are all fixedly connected by threads.