CN115350427A

CN115350427A - Fire-fighting foam foaming device, system and foaming method

Info

Publication number: CN115350427A
Application number: CN202211069475.7A
Authority: CN
Inventors: 田志坚; 李前进; 赵阳光; 白冰; 季经纬
Original assignee: XCMG Fire Fighting Safety Equipment Co Ltd
Current assignee: XCMG Fire Fighting Safety Equipment Co Ltd
Priority date: 2022-08-31
Filing date: 2022-08-31
Publication date: 2022-11-18
Anticipated expiration: 2042-08-31
Also published as: CN115350427B

Abstract

The invention discloses a fire-fighting foam foaming device, a fire-fighting foam foaming system and a fire-fighting foam foaming method, relates to the technical field of compressed gas foam fire extinguishing, and aims to improve the foaming effect of fire-fighting foam. The fire-fighting foam generator comprises a body and a baffle. The body comprises a through hole; the flow area of the middle region of the through hole is larger than the flow areas of the two ends of the through hole. The baffle is arranged in the middle area of the through hole. Above-mentioned technical scheme, behind the foam inflow body that conveys, under the effect of baffle, the big foam that the foam formed in transportation process can be broken once more to form even tiny foam, and then improve the foaming effect, improve the fire behavior of foam.

Description

Fire-fighting foam foaming device, system and foaming method

Technical Field

The invention relates to the technical field of compressed gas foam fire extinguishing, in particular to a fire-fighting foam foaming device, a fire-fighting foam foaming system and a fire-fighting foam foaming method.

Background

The compressed gas foam system is a novel fire extinguishing system and comprises a fire pump, a compressed gas system, a foam proportion mixing system, a spraying device, a pipeline system and the like. Compressed gas foam systems are used to generate compressed gas foam to extinguish fires. Compressed gas foam systems are divided into mobile systems and stationary systems, for example: the compressed gas foam fire truck is provided with a movable vehicle-mounted compressed gas foam system, and the extra-high voltage converter station is provided with a fixed compressed gas foam system.

The compressed gas foam is a bubble group with smaller granularity, fine and uniform foam structure and surface surrounded by a liquid film, and can float on the surface of common combustible liquid to form a foam covering layer and adhere to the surface of common combustible solid due to small specific gravity and certain viscosity, so that the fire extinguishing agent is high in fire extinguishing efficiency, low in water consumption and recommended to be used in various fields and places such as petroleum, chemical engineering, storage, transformer substations and the like. The research of fire extinguishing technology in recent years has also proved that the compressed gas foam is obviously superior to the traditional common fire-fighting foam generated at the foam muzzle or through a foam generator by the negative pressure air suction principle in the aspects of foam liquid-separating time, stability, fire extinguishing and anti-reburning efficiency.

The petrochemical engineering relates to a plurality of types and large quantity of inflammable and explosive substances, once a fire disaster happens, the combustion speed is high, the fire development is rapid, a large-area three-dimensional fire disaster is easy to form, the reburning is easy to happen, and the difficulty in fighting fire is very high. The flow rate of the foam mixed liquid of the prior mature positive pressure type foam system is 20-100L/s, and once full liquid level combustion occurs in 5-10 cubic meters of oil tanks or flammable liquid storage tanks in petrochemical enterprises, the flow rate of the foam mixed liquid of the positive pressure type foam system required by the storage tank for extinguishing the fire is required to be more than 120-200L/s for supplying strength, so that the combustion liquid level can be quickly covered. To achieve this supply strength, current fixed systems in tank farms are implemented with multiple foam systems.

The inventor finds that at least the following problems exist in the prior art: the respective spraying devices are uniformly installed on the storage tank, so that the composition cost of the fire extinguishing system is increased and the foam can be reliably delivered and sprayed to the fire site. However, for a compressed gas foam fire engine, the compressed gas foam system cannot supply a large flow of compressed foam, so it is difficult to achieve a longer fire monitor range and a larger fire-fighting operation range. Therefore, the development of a high-flow compressed gas foam production device to meet the high efficiency and economic requirements of large petrochemical fire suppression is urgently needed.

Disclosure of Invention

The invention provides a fire-fighting foam foaming device, a fire-fighting foam foaming system and a fire-fighting foam foaming method, which are used for improving the foaming effect of fire-fighting foam.

The embodiment of the invention provides a fire-fighting foam foaming device, which comprises:

a body including a through hole; the flow area of the middle area of the through hole is larger than the flow areas of the two ends of the through hole; and

and the baffle is arranged in the middle area of the through hole.

In some embodiments, the body is configured as a solid of revolution, the length direction of the baffle is along the radial direction of the through hole, and the maximum extension plane of the baffle is parallel to the cross section of the body.

In some embodiments, the size of one end of the baffle is larger than the size of the other end of the baffle; one end of the baffle is fixedly connected with the inner wall of the through hole, and the other end of the baffle faces to the central axis of the through hole.

In some embodiments, the baffle is configured to be conical and the angle of taper of the baffle is between 9 ° and 19 °.

In some embodiments, the number of the baffles is multiple, and the baffles are distributed along the circumferential direction of the through hole.

In some embodiments, the axial length of the through hole is greater than the diameter of the two end openings of the through hole.

In some embodiments, the maximum diameter of the through hole is 1.1 to 1.25 times the diameter of the opening at both ends of the through hole.

The embodiment of the invention provides a fire-fighting foam foaming system, which comprises:

a fire fighting foam foaming device configured to foam the foam mixture, the compressed gas, into fire fighting foam; and

according to the fire-fighting foam foaming device provided by any technical scheme, the fire-fighting foam foaming device is installed at the downstream of the fire-fighting foam foaming device and is connected with the fire-fighting foam foaming device in series, so that fire-fighting foam conveyed by the fire-fighting foam foaming device is subjected to secondary foaming.

In some embodiments, the fire fighting foam foaming device comprises:

a two-phase flow injection seat comprising a first flow path and a second flow path which are independent of each other;

the air nozzle assembly comprises a liquid inlet hole, an air inlet hole, a first air outlet hole and a flow guide part; the liquid inlet aperture is in fluid communication with the first flow path and is located downstream of the first flow path; the inlet orifice is in fluid communication with the second flow path and is located downstream of the second flow path; and

a foam mixing chamber downstream of the first flow path, the second flow path, and in fluid communication with both the first flow path and the second flow path; the first air outlet and the flow guide part extend into the foam mixing chamber; the first air outlet hole and the flow guide portion are configured such that the air flow output via the air nozzle assembly flows to different positions in a radial direction of the foam mixing chamber.

In some embodiments, the flow guide comprises:

and the second air outlet hole and the first air outlet hole are positioned at different positions in the radial direction of the foam mixing chamber.

In some embodiments, the air nozzle assembly comprises:

the mounting plate is attached to and fixed with the two-phase flow injection seat; the mounting plate is provided with a liquid inlet hole which is communicated with the first flow path of the two-phase flow injection seat and the air inlet hole which is communicated with the second flow path;

the axial pipe is arranged on one side of the mounting plate, which is far away from the two-phase flow injection seat; the axial line of the axial pipe is parallel to the central axis of the two-phase flow injection seat; the axial tube is in fluid communication with the air inlet of the mounting plate; and

the axial line of the radial pipe is intersected with the axial line of the axial pipe, one end of the radial pipe is in fluid communication with the axial pipe, and the other end of the radial pipe is located on one side, facing the axial line of the two-phase flow injection seat, of the axial pipe.

In some embodiments, the number of the axial tubes is plural, and the plural axial tubes are arranged dispersedly around the circumference of the mounting plate.

In some embodiments, the other end of the axial tube is distal from the two-phase flow injection seat; the other end of the axial pipe is used as the first air outlet and is open; the other end of the axial tube faces the inner wall of the foam mixing chamber.

In some embodiments, the other end of the radial tube is distal from the axial tube, the other end of the radial tube being closed; the side wall of the radial pipe close to the other end of the axial pipe is provided with the second air outlet hole;

the axial direction of the second air outlet hole is parallel to the central axis of the two-phase flow injection seat, or the axial direction of the second air outlet hole is intersected with the central axis of the two-phase flow injection seat, and the included angle is smaller than 90 degrees.

In some embodiments, the flow guide comprises:

the guide plate is positioned near the first air outlet; the deflector is configured to deflect a portion of the air stream output via the first outlet aperture to a position proximate a central axis of the foam mixing chamber.

In some embodiments, the air nozzle assembly further comprises:

the mounting plate is attached and fixed with the two-phase flow injection seat; the mounting plate is provided with the air inlet hole which is communicated with the second flow path of the two-phase flow injection seat; and

the axial pipe is arranged on one side of the mounting plate, which is far away from the two-phase flow injection seat; the axial line of the axial pipe is parallel to the central axis of the two-phase flow injection seat; said axial tube being in fluid communication with said air inlet of said mounting plate;

wherein the baffle is fixedly connected to the axial tube, the baffle being configured without holes; the baffle is configured to create a negative pressure region on a side of the baffle itself remote from the mounting plate such that a portion of the airflow output by the axial tube flows to the negative pressure region.

In some embodiments, the first flow path is located on a central axis of the two-phase flow injection seat; the second flow path is located outside the first flow path in a radial direction of the two-phase flow injection seat.

In some embodiments, the fire fighting foam foaming device further comprises:

a first inlet tube, the first flow path being downstream of the first inlet tube and in fluid communication with the first inlet tube; and

a first outlet tube mounted downstream of the foam mixing chamber.

In some embodiments, the inner wall of the foam mixing chamber is tapered; the flow area of the inlet of the foam mixing chamber is larger than the flow area of the outlet of the foam mixing chamber.

In some embodiments, the fire fighting foam foaming system further comprises:

a gas supply flow path located upstream of the second flow path of the two-phase flow injection seat to supply gas to the two-phase flow injection seat;

a foam raw liquid supply flow path located upstream of the first flow path of the two-phase flow injection seat to supply a foam raw liquid to the two-phase flow injection seat; and

a water supply flow path also located upstream of the first flow path of the two-phase flow injection seat to supply water to the two-phase flow injection seat.

In some embodiments, the fire fighting foam foaming system further comprises:

the water spraying branch is arranged in parallel with the fire-fighting foam foaming device; one end of the water spray branch is in fluid communication with the water supply flow path; the other end of the water spraying branch is connected with the first outlet pipe in parallel; and

a foam spraying branch communicated with the water supply flow path; the foam injection branch is positioned between the water supply flow path and the first flow path and is communicated with the water supply flow path and the first flow path in a fluid mode;

wherein the water supply flow path is selectively in fluid communication with at least one of the water spray branch and the foam spray branch.

In some embodiments, the fire fighting foam foaming system further comprises:

a delivery tube in fluid communication with the fire fighting foam foamer, the delivery tube being located downstream of the fire fighting foam foamer; and

and the revolving body is connected with the conveying pipe.

In some embodiments, the fire fighting foam foaming system further comprises:

an ejector mounted downstream of the delivery pipe; the distance between the ejector and the fire-fighting foam foaming device is 5-10 times larger than the maximum diameter of a pipeline between the fire-fighting foam foaming device and the ejector.

In some embodiments, the length of the pipeline between the fire fighting foam foaming device and the fire fighting foam foamer is 10 to 20 times or more greater than the maximum diameter of the pipeline.

The embodiment of the invention also provides a fire-fighting foam foaming method, which is realized by adopting the fire-fighting foam foaming system provided by any technical scheme of the invention, and the fire-fighting foam foaming method comprises the following steps:

when the foam extinguishing agent needs to be sprayed, the foam extinguishing agent is sprayed according to a set first flow rate V _Ml Delivering a foam mixture to a first inlet pipe of the fire fighting foam foaming device;

according to the set second flow velocity V _G Delivering compressed gas to a second flow path of a two-phase flow injection seat of the fire fighting foam foaming device;

according to a set third flow velocity V _F1 And conveying the fluid output by the fire-fighting foam foaming device to a fire-fighting foam foaming device.

In some embodiments, the foam mixture first flow rate V _Ml 6-8 m/s; and/or

A second flow rate V of the delivered compressed air _G 6-8 m/s; and/or

The V is _F1 5-10 m/s; and/or

The flow velocity of foam mixed liquid injected into the inlet of the foam mixing chamber of the fire-fighting foam foaming device is V _1I ，V _1I Is 2m/s to 5m/s; and/or

The flow velocity of compressed gas injected into the inlet of the foam mixing chamber of the fire-fighting foam foaming device is V _1G ，V _1G Is 10m/s to 20m/s; and/or

The flow velocity of the foam outflow appearance at the outlet of the foam mixing chamber of the fire-fighting foam foaming device is V _1O ，V _1O Is 4m/s to 8m/s.

In some embodiments, the fire fighting foam foaming method further comprises the steps of:

according to the set fourth flow velocity V _F2 And conveying the fluid output by the fire fighting foam foaming device to an ejector.

In some embodiments, the V _F2 Is 6 to 12m/s.

The fire-fighting foam foaming device provided by the technical scheme is particularly suitable for a large-flow compressed gas foam system, and can carry out secondary foaming on foams conveyed by other foaming devices. In the process of delivering the high-flow compressed gas foam, because the flow of the fire-fighting pipeline is large, on one hand, the foam mixed liquid which is foamed only once may be incompletely foamed; on the other hand, the phenomena that the foams are easy to break, the gas overflows from the bubble flow and is integrated into large bubbles and the like exist due to more changes or reducing in pipeline conveying. Fire control foam maker includes body and baffle, and behind the foam inflow body that conveys, under the effect of baffle, big foam can be broken once more to form even little foam, and then improve the foaming effect, improve the fire behavior of foam.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention and do not constitute a limitation of the invention. In the drawings:

fig. 1 is a schematic diagram illustrating a fire fighting foam foaming system according to an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of a fire fighting foam foaming device provided by an embodiment of the invention.

FIG. 3 isbase:Sub>A schematic sectional view A-A of FIG. 2.

Fig. 4 is a schematic sectional view B-B of fig. 2.

Fig. 5 is a schematic structural diagram of an air nozzle assembly of a fire fighting foam foaming device according to an embodiment of the present invention.

Fig. 6 is a schematic diagram of a fire fighting foam foaming system according to another embodiment of the present invention.

Fig. 7 is a schematic structural diagram of a fire fighting foam foaming device according to another embodiment of the present invention.

FIG. 8 is a schematic cross-sectional view of M-M of FIG. 7.

Fig. 9 is a schematic cross-sectional view of fig. 7 taken at N-N.

Fig. 10 is a schematic cross-sectional view P of fig. 7.

Fig. 11 is a schematic structural diagram of a fire fighting foam generator of the fire fighting foam generating system according to the embodiment of the present invention.

Fig. 12 is a schematic cross-sectional view D-D of fig. 11.

Fig. 13 is a schematic view of a method for foaming fire fighting foam according to an embodiment of the present invention.

Reference numerals:

100. a fire fighting foam foaming device; 200. a gas supply flow path; 300. a foam raw liquid supply flow path; 400. a water supply flow path; 500. a water spray branch; 600. spraying a foam branch; 700. a fire fighting foam foamer; 810. a delivery pipe; 820. a revolving body; 830. an ejector; 840. a foam mixed liquid switch valve; 850. a controller;

110. a two-phase flow injection seat; 120. an air nozzle assembly; 130. a foam mixing chamber; 140. a first inlet tube; 150. a first outlet pipe;

111. a first flow path; 112. a second flow path;

121. a liquid inlet hole; 122. an air intake; 123. a first air outlet hole; 124. a flow guide part; 124' and a second air outlet; 124", a baffle; 125. mounting a plate; 126. an axial tube; 127. a radial tube;

201. an air compressor; 202. a gas distribution valve; 203. a cooler; 204. a first gas filter; 205. a second gas filter; 206. an air flow meter; 207. a one-way valve; 208. a first pressure gauge; 209. an intake throttle valve;

300a, a foam stock solution suction branch; 300b, a flushing branch; 301. a foam pipette valve; 302. flushing the water inlet valve; 303. a foam pump; 304. a check valve; 305. a foam flow meter; 306. a foam concentrate interface;

401. a filter; 402. a water pump; 403. a vacuum pump; 404. a check valve; 405. a vacuum gauge; 406. a water flow meter; 407. a water inlet pipe interface;

501. a first switching valve; 601. a second switching valve; 602. a second pressure gauge;

701. a body; 702. and a baffle plate.

Detailed Description

The technical solution provided by the present invention will be explained in more detail with reference to fig. 1 to 13.

The inventor finds that in the fire fighting industry, the existing mature and reliable foam mixing device of a medium and small-sized compressed gas foam system (the foam mixed liquid flow is 20-100L/s) adopts a static mixer or a plurality of static mixers which are connected in series/in parallel to form a group which is connected in a pipeline, and has the advantages of simple structure, reliable performance and no need of additional driving force. These static mixers can be divided in principle into two main categories, one starting from the design of different fluid mixing and injection structures, such as: (1) dividing any one of the gas phase flow or the liquid phase flow into a plurality of finer flow bundles to be injected into the outer interface of the other phase flow for mixing, (2) dividing any one of the gas phase flow or the liquid phase flow into a plurality of finer flow bundles to be injected into the inner part of the other phase flow for mixing, and the like; the other type starts from designing different spoiler structures, such as superposed mesh plates, spiral deflectors, three-dimensional grid plates, conical spoilers and the like. The designs are finally designed to ensure that the gas phase flow is better dispersed by the liquid phase flow, and the two-phase flow can be more uniformly mixed under the impact action of the turbulence piece to form a bubble flow with fine particles and uniform foam distribution. Of course, in order to enhance the foaming effect of the two types of static mixers, some designs design that a reducing structure of a venturi tube or a Laval tube is designed in the front pipeline and the rear pipeline which are connected with the static mixers on the basis of the foaming effect, so that the effect of mutual impact mixing of two-phase flows is further enhanced.

The mechanism of generating foam in the compressed gas foam system is that firstly, foam stock solution and water are uniformly mixed according to a certain proportion, then, foam mixed solution is mixed with compressed gas for foaming, namely, the compressed gas with a certain proportion is injected into the foam mixed solution, and foam is generated after the compressed gas and the compressed gas are mixed through the impact of two-phase flow.

The fire-fighting foam formed by injecting the compressed gas has the advantages that the stability, the foamability and the fire-fighting performance are closely related to the physical properties of foam stock solution, water and gas, the chemical composition of the foam stock solution and the like, and the main factors influencing the performance in the preparation process are the factors of the foam mixed solution ratio, the gas-liquid ratio, the mixing pressure, the gas-liquid two-phase surface contact area, the two-phase mixing uniformity and the like.

The generation of compressed gas foam is actually the mixing and conveying process of gas-liquid two-phase flow, and the inventor finds through research that the gas-liquid two-phase flow can form five flow patterns according to the difference of injected gas velocity and liquid velocity, pipe diameter, fluid properties and the like: annular flow, plug flow, liquid throttling, bubble flow and mist flow, wherein when the main body is in a bubble flow type, the foam is formed in the best quality, the average bubble size is small, the number of bubbles is large, and the bubbles are uniformly dispersed in a continuous liquid phase.

The existing shaping products and engineering practices show that the process control of the foam mixed liquid proportion, the gas-liquid ratio, the mixed pressure and the like in a compressed gas foam system forms a mature and reliable technology in the industry, but the mature technology and the mature technology do not form in the aspects of controlling the contact area of the gas-liquid two-phase surface and the mixing uniformity of the two phases. Especially for a high-flow compressed gas foam system with foam mixed liquid flow rate larger than 150L/s, as the two-phase flow rate is obviously increased, in order to reduce the pressure loss of a pipeline, the drift diameter of a fire-fighting foam foaming device and a related conveying pipeline is also correspondingly and obviously increased, the original foam mixing device structure which is suitable for the compressed gas foam system with the flow rate less than or equal to 100L/s is difficult to provide the contact area and the way for fully mixing and foaming gas-liquid two-phase flow, and new problems appear in use, such as: (1) the original uniformly mixed bubble flow cannot be achieved, and the quality of the foam is deteriorated; (2) the overflow pressure loss of the foam mixing device is too large; (3) the device occupies a large space and is difficult to place on a vehicle; (4) complex structure, poor reliability and the like.

After further research, the inventor finds that under the condition that the chemical components of the foam stock solution and the physical properties of the foam stock solution, water and gas are determined, the preparation quality of the fire-fighting foam in a large-flow compressed gas foam system is actually influenced, and two links mainly exist: namely, one is the mixing and foaming effect of the foam mixing chamber, and the other is the development change in pipeline transportation after foaming.

Therefore, the inventor provides a fire-fighting foam foaming device suitable for a large-flow compressed gas foam system, which can enable fire-fighting foam to be foamed again in the conveying process so as to improve the quality of the fire-fighting foam which is finally sprayed out, meet the successful application in a vehicle-mounted or fixed system and realize better fire-fighting efficiency.

The terms or expressions used herein are to be interpreted.

The fire-fighting foam is a bubble group which has small volume, is surrounded by a liquid film on the surface and is used for fire fighting. Because the specific gravity is far less than that of the general combustible liquid, the liquid can float on the surface of the liquid to form a foam covering layer. Meanwhile, the fire-fighting foam has certain viscosity and can be adhered to the surface of a common combustible solid.

The preparation method of the fire-fighting foam comprises the following steps: the foam stock solution and water are uniformly mixed according to a certain proportion, and then the foam mixed solution is mixed with gas for foaming, so that the fire extinguishing agent with fire extinguishing effect, namely the fire-fighting foam, is finally formed.

The foam quality and fire extinguishing performance of the fire-fighting foam are mainly related to the physical properties of foam stock solution, water and gas, the foam mixed solution proportion, the gas-liquid ratio, the mixing pressure, the gas-liquid mixing uniformity, the gas-liquid two-phase surface contact area and other factors.

Foam stock solution: can be mixed with water in a proper mixing ratio to form a concentrated liquid of the foaming solution.

Foam mixed liquid: the foam solution is prepared by mixing the foam solution and water according to a specific mixing ratio.

Expansion ratio: the ratio of the volume of foam to the volume of foam mixture that forms the foam. Low multiple foam: fire extinguishing foam with expansion ratio lower than 20. Wet foam: foams with a foaming ratio lower than 10 times. Dry foaming: a foam having a foaming ratio of not less than 10 times.

Compressed gas foam fire engine: mainly equips a water tank and a foam liquid tank, and sprays foam to extinguish fire through a compressed gas foam system.

Foam proportion mixing system: the system consists of a foam proportion mixer, a foam stock pump, a control device, a pipeline device and the like, and can mix water and foam stock solution according to a certain proportion.

Compressed gas foam system: the device mainly comprises a fire pump, a compressed gas system, a foam proportion mixing system, an injection device, a pipeline system and the like, and can generate compressed gas foam.

The terms and dimensions are used herein for descriptive purposes.

D1 is the diameter of the first channel 111 and also the diameter of the first inlet pipe 140.

D2 is the inlet diameter of the foam mixing chamber 130.

D3 is the diameter of the primary outlet tube 150, which is also the outlet diameter of the foam mixing chamber 130.

D4 is the diameter of the circumferential surface on which the other ends of all the radial tubes 127 are located.

d1 is the diameter of both ends of the body 701.

d2 is the diameter of the middle of the body 701.

d3 is the diameter of the circumferential surface on which the other end of all of the baffles 702 is located.

L1 is the axial length of the foam mixing chamber 130.

L2 is the axial length of the body 701.

L3 is the thickness of the baffle 702.

L4 is the width of the baffle 702.

L5 is the length of the baffle 124 ".

L6 is the width of the other end of the baffle 124 ".

α is the cone angle of the baffle 702.

Delta is the cone angle of the baffle 124 ".

Referring to fig. 1 to 2, an embodiment of the present invention provides a fire fighting foam foaming device 100 for forming foam by a foam mixture under the action of compressed gas. The fire fighting foam foaming device 100 includes a two-phase flow injection seat 110, an air nozzle assembly 120, and a foam mixing chamber 130. The two-phase flow inlet 110 includes a first flow path 111 and a second flow path 112 that are independent of each other. Referring to fig. 2 and 5, the air nozzle assembly 120 includes an inlet aperture 121, an inlet aperture 122, a first outlet aperture 123, and a second outlet aperture 124'. The liquid inlet hole 121 is in fluid communication with the first flow path 111, and the liquid inlet hole 121 is located downstream of the first flow path 111. The intake aperture 122 is in fluid communication with the second flow path 112 and is located downstream of the second flow path 112. A foam mixing chamber 130 is mounted downstream of the second flow path 112 and is in fluid communication with the second flow path 112; the first air outlet hole 123 and the second air outlet hole 124' both extend into the foam mixing chamber 130; the first and second outlet holes 123 and 124' are located at different positions in the radial direction of the foam mixing chamber 130.

The two-phase flow injection seat 110 is used for receiving foam mixed liquid and compressed gas. The foam mixture enters the two-phase flow injection seat 110 and then flows directly along the first flow path 111 to the foam mixing chamber 130. After entering the two-phase flow injection seat 110, the compressed gas enters the air nozzle assembly 120 along the second flow path 112, and then enters the foam mixing chamber 130 from the air nozzle assembly 120 to interact with the foam mixture entering the foam mixing chamber 130 to generate fire fighting foam.

To facilitate connecting the fire fighting foam foaming device 100 with other components, referring to fig. 2, in some embodiments, the fire fighting foam foaming device 100 further includes a first inlet pipe 140 and a first outlet pipe 150. The first flow path 111 is located downstream of the first inlet tube 140 and is in fluid communication with the first inlet tube 140. A first outlet tube 150 is installed downstream of the foam mixing chamber 130.

The specific implementation of the various components of the fire fighting foam foaming device 100 will be described in detail below with respect to the flow path of the fluid into the fire fighting foam foaming device 100.

As introduced above, the fluid entering the fire fighting foam foaming device 100 is classified into two categories: foam mixed liquid and compressed gas. The foam mixed liquid is a mixture of foam stock solution and water. The foam mixture enters the first flow path 111 of the two-phase flow inlet block 110 from the first inlet pipe 140, and the fluid entering the first flow path 111 flows along the solid arrow S1, see fig. 2. The compressed gas then flows from the external conduit of the fire fighting foam foaming device 100 along the second flow path 112 into the two-phase flow injection seat 110, and the fluid entering the second flow path 112 flows along the dashed arrow S2, see fig. 2.

Specifically, referring to fig. 2, the foam mixture is fed into first inlet pipe 140, and then the foam mixture enters first flow path 111 of two-phase flow inlet block 110 along first inlet pipe 140. The central axis of the first inlet tube 140 coincides with the central axis of the two-phase flow injection seat 110. The foam mixture in the first flow path 111 of the two-phase flow injection seat 110 then flows into the liquid inlet hole 121 of the air nozzle assembly 120, see fig. 5. The liquid inlet hole 121 is located at the middle position of the air nozzle assembly 120, and the central axis of the liquid inlet hole 121 is also coincident with the central axis of the two-phase flow injection seat 110. The flow area of the liquid inlet hole 121 is slightly larger than the flow area of the first inlet pipe 140 and the flow area of the first flow path 111 of the two-phase flow inlet block 110. Here, the first inlet pipe 140 and the first flow path 111 are both cylindrical structures, for example. The foam mixture then flows out of the inlet opening 121 of the air nozzle assembly 120 and then into the foam mixing chamber 130 to be mixed with the compressed gas output from the second flow path 112 of the two-phase flow injection seat 110 to be foamed into foam.

With continued reference to FIG. 2, the compressed gas enters the second flow path 112 of the two-phase flow injection block 110 from an external conduit and then enters the air nozzle assembly 120 along the air inlet aperture 122 of the air nozzle assembly 120. Referring to FIG. 5, the compressed gas entering the air nozzle assembly 120 is divided into two streams, one stream exiting the air nozzle assembly 120 through the first exit aperture 123, i.e., stream S21; the other stream exits the air nozzle assembly 120 at a second exit aperture 124', i.e., stream S22. The first outlet aperture 123 has a diameter D5 and the second outlet aperture 124' has a diameter D6.

Referring to fig. 2, in some embodiments, the first flow path 111 is located on a central axis of the two-phase flow injection seat 110; the first flow path 111 is specifically an air inlet hole 122 penetrating the two-phase flow injection seat 110 in the axial direction thereof. The second flow path 112 includes two sections, a first section being a gas hole extending along the radial direction of the two-phase flow injection seat 110, and a second section being an annular groove having an axis parallel to the axial direction of the two-phase flow injection seat 110, the annular groove being in fluid communication with the gas hole of the first section. The external compressed gas firstly enters the first section branch and then flows to the second section branch. The second flow path 112 is located outside the first flow path 111 in the radial direction of the two-phase flow injection seat 110. By adopting the structure of the two-phase flow injection seat 110, the first flow path 111 and the second flow path 112 can be independent and are not in series flow or communication with each other, and the first flow path 111 and the second flow path 112 have a certain overlapping area in the axial direction of the two-phase flow injection seat 110. The space size of the two-phase flow injection seat 110 is effectively utilized, the structure occupied by the two-phase flow injection seat 110 is small in size, and the structure is compact and reasonable.

The air nozzle assembly 120 is fixedly coupled to the two-phase flow injection seat 110. The air inlet aperture 122 of the air nozzle assembly 120 is located downstream of the second flow path 112 of the two-phase flow injection seat 110.

The compressed gas entering the air nozzle assembly 120 is split and emitted through the first and second outlet holes 123 and 124'. The first outlet hole 123 and the second outlet hole 124' are located at different positions in the radial direction of the foam mixing chamber 130 as viewed in the radial direction of the foam mixing chamber 130. The first outlet aperture 123 is closer to the radial edge of the foam mixing chamber 130 and the second outlet aperture 124' is closer to the central axis of the foam mixing chamber 130.

Air nozzle subassembly 120 adopts above-mentioned structure, has realized cleverly that compressed gas has carried out the intensive mixing from the surface and the inside of foam mixture liquid column, has enlarged the area of contact of compressed air with foam, water, and first venthole 123, first venthole 123 all are located the inside of foam mixing chamber 130 in addition, have effectively reduced because air nozzle subassembly 120 occupies the excessive pressure loss that the position caused.

Referring to fig. 2 and 5, in some embodiments, the air nozzle assembly 120 includes a mounting plate 125, an axial tube 126, and a radial tube 127. The mounting plate 125 is a flat plate, and the thickness of the flat plate is preferably as thin as possible to satisfy the requirement of fixed installation, so that the entire fire fighting foam generating device 100 has a more compact and compact structure. The mounting plate 125 is attached to and secured to the two-phase flow injection seat 110, such as by bolting, welding, riveting, or the like. The mounting plate 125 defines an inlet aperture 122 in fluid communication with the second flow path 112 of the two-phase fluid inlet block 110 and an inlet aperture 121 in fluid communication with the first flow path 111. The axial tube 126 is mounted to the mounting plate 125 on a side thereof remote from the two-phase flow injection seat 110, and the axial tube 126 and the mounting plate 125 are welded to each other. The axis of the radial tube 127 is perpendicular to the central axis of the two-phase flow injection seat 110. The axial tube 126 is in fluid communication with the air intake aperture 122 of the mounting plate 125. The compressed gas enters the axial tube 126 along the inlet holes 122 of the mounting plate 125. The central axis of the radial tube 127 intersects the central axis of the axial tube 126, and one end of the radial tube 127 is in fluid communication with the axial tube 126, specifically, the radial tube 127 is mounted at a position near the downstream end of the axial tube 126. This configuration allows radial tube 127 to be axially spaced from the inlet of foam mixing chamber 130 such that the foam mixture interacts with the compressed gas output from radial tube 127 in a relatively stable state. The other end of the radial tube 127 remote from the axial tube 126 is located on the side of the axial tube 126 facing the central axis of the two-phase flow injection seat 110.

Above-mentioned technical scheme, the compressed gas of axial pipe 126 output and the liquid column that the foam mixed liquid formed are located the regional part interact of circumference surface, and the compressed gas of radial pipe 127 output can stretch into the central point that the foam mixed liquid put to the liquid column that forms with the foam mixed liquid is located the regional part interact of center, like this greatly increased the area of contact of compressed gas and foam mixed liquid, improved the foaming effect. Also, the arrangement of the axial tubes 126 and radial tubes 127 reduces the resistance to liquid flow impingement.

With continued reference to fig. 2, in some embodiments, the other end of the radial tube 127 is distal from the axial tube 126, the other end of the radial tube 127 being closed; the side wall of the radial pipe 127 close to the other end of the axial pipe 126 is provided with a second air outlet 124'; the axial direction of the second air outlet 124 'is parallel to the central axis of the two-phase flow injection seat 110, or the axial direction of the second air outlet 124' intersects the central axis of the two-phase flow injection seat 110, and the included angle is smaller than 90 °.

With continued reference to fig. 2, in some embodiments, the other end of axial tube 126 is distal from two-phase flow injection seat 110, and the other end of axial tube 126 is open as first outlet aperture 123. The other end of the axial tube 126 faces the inner wall of the foam mixing chamber 130, i.e., the tapered inner wall of the foam mixing chamber 130.

Referring to fig. 3 and 4, in some embodiments, the number of the axial tubes 126 is multiple, such as 8 to 10, and the multiple axial tubes 126 are distributed around the circumference of the mounting plate 125, and may be uniformly distributed. So arranged, the compressed gas output by the axial tube 126 can interact at multiple locations in the circumferential surface area of the liquid column formed by the foam mixture to enhance the foaming effect.

Referring to fig. 3 and 4, in some embodiments, the number of the radial tubes 127 is multiple, specifically, 8 to 10. The axial tubes 126 and the radial tubes 127 are arranged in one-to-one correspondence.

Referring to fig. 2, 3 or 5, in some embodiments, each axial tube 126 is provided with a first outlet aperture 123. Each radial tube 127 is provided with a plurality of second outlet holes 124'. The first outlet holes 123 have a relatively large flow area, and each of the second outlet holes 124' is a micro-hole. In some embodiments, the flow area of the other end of the axial tube 126 is 1.5 to 2 times the flow area of all of the second outlet holes 124' of the radial tubes 127 that are in fluid communication with the axial tube 126. The distance H1 (see FIG. 2) from the top end of the stem inserted into the middle of the foam mixing chamber 130 to the axis of the foam mixing chamber 130 is 0.15-0.2 times of the inflow path D1 (see FIG. 2) of the foam mixture of the two-phase flow injection seat 110, so that the air flow output by the radial tube 127 can fully interact with the interior of the foam mixture.

With continued reference to fig. 3 and 4, in some embodiments, the other ends of all of the radial tubes 127 are located on the same circumferential surface, and the diameter D4 of the circumferential surface is 0.3 to 0.4 times the diameter D1 of the first flow path 111.

In some embodiments, the diameter of the first flow path 111 and the diameter of the first inlet tube 140 are equal, both D1. The diameter of the first outlet tube 150 is D3. In some embodiments, the flow area of the first inlet tube 140 is the same as the flow area of the first outlet tube 150. I.e., D1 and D3 are equal.

According to the technical scheme, the axial pipe 126 and the radial pipe 127 are adopted to output the compressed gas, so that the compressed gas is fully mixed from the outer surface and the inner part of the foam mixed liquid column, the contact area of two-phase flow is enlarged, the overflowing pressure loss is reduced, the filling resistance of the compressed gas is reduced, and the gas-liquid two-phase opposite-flushing stirring path is optimized, so that the foaming effects of more uniform mixing and smaller foam granularity are realized.

Moreover, in the above technical solution, the air nozzle assembly 120 is located inside the cylindrical hole of the foam mixing chamber 130, and the air nozzle assembly 120 adopts a reasonable T-shaped shaft hole design, so as to ensure that the minimum flow area of the foam mixing chamber 130 is not less than the inflow area of the foam mixture of the two-phase flow injection seat 110. This fire control foam foaming device 100 has realized that compressed gas carries out intensive mixing from the surface and the inside of foam mixture liquid column, has enlarged the area of contact of two-phase flow, has effectively reduced moreover because the air nozzle occupies the excessive flow pressure loss that causes. The air nozzle assembly 120 is designed by a reasonable number of nozzle holes and a reasonable structural size, so that the minimum flow area of the foam mixing chamber 130 is not smaller than the inflow area of the foam mixture of the two-phase flow injection seat 110.

With continued reference to fig. 2, the inner walls of the foam mixing chamber 130 are configured to be conical; the flow area of the inlet of the foam mixing chamber 130 is larger than the flow area of the outlet of the foam mixing chamber 130, i.e. D2 is larger than D3.

Foam mixing chamber 130 adopts the design of awl cylindricality, variable cross section, realized on the one hand that foam mixed liquid can form the relative low-pressure region near conical surface department when foam mixing chamber 130 flows through, be favorable to first venthole 123 and second venthole 124' to pour into the mixture into, on the other hand most compressed gas through the first venthole 123 that is on a parallel with the conveying line axis with the conical surface, liquid phase near the conical surface strikes each other to and stir and strike each other with the liquid phase after the conical surface reflection again, thereby realize mixing more evenly, the foaming effect that the foam particle size is littleer.

In some embodiments, the foam mixing chamber 130 has an axial length L1, the outlet diameter of the foam mixing chamber 130 is D3, and L1 is 0.35 to 0.5 times D3.

In some embodiments, the inner wall of the foam mixing chamber 130 is angled from the central axis of the foam mixing chamber 130 by an angle θ, which is 40 ° to 50 °.

As described above, the foam mixing chamber 130 is internally configured as a tapered cylindrical cross-sectional hole, the foam outflow taper diameter D3 of the foam mixing chamber 130 is the same as the foam mixture inflow diameter D1 of the two-phase flow inlet 110, and the cylindrical opening diameter D2 of the foam mixing chamber 130 is 1.5 times the taper diameter D3. That is, the inlet diameter D2 of the bubble mixing chamber 130 is 1.3 to 1.7 times, specifically, 1.5 times, the outlet diameter D3 of the bubble mixing chamber 130. By adopting the proportion parameters, the foaming effect is effectively improved.

In some embodiments, the axial length L1 of the foam mixing chamber 130 is 0.4 to 0.6 times, such as 0.4, 0.5, 0.6 times, the outlet diameter D3 of the foam mixing chamber 130. By adopting the proportion parameters, the foaming time is in a better range, and the foaming effect is greatly improved.

By adopting the parameters, the pressure loss of the pipeline is reduced, the foaming quality is improved, and a more uniform foam flow with better fire extinguishing performance is formed.

Referring to fig. 6-10, further embodiments are described below.

The present embodiment is different from the above-described embodiments in that the flow guide portion 124 is implemented differently. The flow guiding portion 124 particularly comprises a flow guiding plate 124", the flow guiding plate 124" being located adjacent to said first outlet aperture 123. The deflector 124 "is configured to deflect a portion of the air stream output through the first outlet aperture 123 to a position near the central axis of the foam mixing chamber 130.

In each of the above embodiments, the flow guide 124 employs the second outlet hole 124'. Since the second outlet hole 124 'and the first outlet hole 123 are located at different positions in the radial direction of the foam mixing chamber 130, the air flow coming out of the second outlet hole 124' is closer to the central axis region of the foam mixed liquid column, and the air flow coming out of the first outlet hole 123 is closer to the circumferential surface region of the foam mixed liquid column.

However, in the present embodiment, the air flow is entirely output into the foam mixing chamber 130 via the first outlet hole 123. The surface of the deflector 124 "blocks the foam mixture entering the foam mixing chamber 130 so that downstream in the direction of flow of the foam mixture, i.e. the side of the deflector 124" facing away from the mounting plate 125, a negative pressure area a is created which results in less foam mixture there. The compressed gas output through the first gas outlet hole 123 can smoothly enter the region and be mixed with the foam mixture therein. The negative pressure region a and the first air outlet 123 are located at different positions in the radial direction of the foam mixing chamber 130, so that compressed air acting on both the central axis region and the circumferential surface region of the foam mixed liquid column entering the foam mixing chamber 130 is provided.

Referring to fig. 10, the baffle 124 "is trapezoidal in shape when viewed from the direction P, and the baffle 124" is thicker at one end and thinner at the other end in connection with the axial tube 126. L5 is 15-30mm, and L6 is 5-8 mm. The taper angle of the guide plate 124' is delta, delta is 15 degrees to 25 degrees, specifically 15 degrees, 18 degrees, 20 degrees, 22 degrees, 25 degrees and the like.

Referring to fig. 7, the inlet diameter D2 of the foam mixing chamber 130 is larger than the outlet diameter D3 of the foam mixing chamber 130, so that the fluid flow in the first flow path 111 can be used to form a low pressure area at the conical cavity annular wall space for the compressed gas to enter; and the side of flow guide 124 "remote from mounting plate 125 also creates a low pressure zone a.

According to the technical scheme, after liquid flow passes through the air nozzle assembly 120, the low-pressure area A formed on the back surface of the air nozzle assembly 120 is skillfully utilized to guide compressed gas to be reflected by the inner conical surface of the foam mixing chamber 130 and enter the middle part of the foam mixing chamber 130 along the back surface of the air nozzle assembly 120, so that the compressed gas is fully mixed from the outer surface and the inner part of a foam mixed liquid column, the contact area of two-phase flow is enlarged, and the overflowing pressure loss caused by the space occupied by the air nozzle assembly 120 is effectively reduced.

Returning to fig. 1 or fig. 6, further embodiments of the present invention further provide a fire fighting foam generating system, which includes a gas supply flow path 200, a foam concentrate supply flow path 300, a water supply flow path 400, and a fire fighting foam generating apparatus 100 according to any of the embodiments of the present invention. The gas supply flow path 200 is located upstream of the second flow path 112 of the two-phase flow injection seat 110 to supply gas to the two-phase flow injection seat 110. The foam concentrate supply flow path 300 is located upstream of the first inlet pipe 140 to supply the foam concentrate to the first inlet pipe 140. The water supply flow path 400 is also located upstream of the first inlet pipe 140 to supply water to the first inlet pipe 140.

The structure, principle and specific implementation of the fire fighting foam foaming system will be described in detail below along the flow direction of each fluid.

First, a part for supplying compressed gas will be described. The gas supply flow path 200 is used to supply compressed gas to the second flow path 112 of the two-phase flow injection seat 110 of the fire fighting foam foaming device 100 described above.

Referring to fig. 1, in some embodiments, the gas supply circuit 200 includes an air compressor 201, a gas distribution valve 202, and a cooler 203. The various components are in fluid communication with one another via conduits. The air compressor 201 is configured to provide compressed air. An intake throttle valve 209 may also be provided upstream of the air compressor 201 to adjust the amount of intake air. Upstream of the intake throttle valve 209, a first air filter 204 may also be provided to filter impurities in the air. Downstream of the air compressor 201, a second air filter 205 is provided to filter out impurities in the compressed air output by the air compressor 201.

In order to accurately detect the pressure of the compressed gas in the gas supply passage 200, a first pressure gauge 208 is provided in the line between the gas distribution valve 202 and the second air filter 205 to detect the pressure of the compressed gas in the line.

A gas distribution valve 202 is provided downstream of the second air filter 205, and the gas distribution valve 202 is specifically installed in a pipeline downstream of the second air filter 205. The gas distribution valve 202 is used for distributing the compressed gas output by the air compressor 201 to supply the compressed gas to the fire fighting foam foaming device 100 according to the set flow parameters. Downstream of the gas distribution valve 202, a cooler 203 is provided. The cooler 203 is used to regulate the temperature of the compressed gas output by the gas distribution valve 202 so that the compressed gas enters the second flow path 112 of the fire fighting foam expansion device 100 according to the set temperature requirement.

In order to accurately control the flow rate of the compressed gas output from the gas supply flow path 200 to the second flow path 112, the gas supply flow path 200 further includes an air flow meter 206. An air flow meter 206 is located downstream of the cooler 203. The flow rate of the compressed gas in the pipeline is collected by the air flow meter 206.

With continued reference to fig. 1, in some embodiments, the gas supply flow path 200 further includes a one-way valve 207, the one-way valve 207 being positioned between the airflow meter 206 and the second flow path 112 such that compressed gas can only flow from the airflow meter 206 to the second flow path 112 without flowing back. Moreover, the possibility of the first flow path liquid flowing back to the gas path in the foam-foaming device 100 in some cases is eliminated.

In some embodiments, the fire fighting foam foaming system further comprises a controller 850, and the controller 850 is communicatively connected to the air compressor 201, the air intake throttle valve 209, the first pressure gauge 208, the gas distribution valve 202, and the air flow meter 206. The controller 850 controls the working states of the air compressor 201, the air inlet throttle valve 209 and the gas distribution valve 202 according to the state parameters collected by the water flow meter 406, the second pressure gauge 602, the second switching valve 601, the foam mixture switching valve 840, the first pressure gauge 208 and the air flow meter 206 to meet the fire extinguishing requirement, so that the parameters of the compressed gas entering the second flow path 112 of the two-phase flow injection seat 110 of the fire-fighting foam foaming device 100 meet the requirement. Parameters such as flow, expression flow rate also called flow rate, etc.

With continued reference to fig. 1, the foam concentrate supply flow path 300 will now be described. The foam raw liquid supply flow path 300 is used to supply the foam raw liquid to the first flow path 111 of the two-phase flow injection seat 110 of the fire fighting foam foaming device 100 described above.

In some embodiments, foam concentrate supply flow path 300 includes foam aspirate valve 301, flush inlet valve 302, and foam pump 303. The various components are in fluid communication with each other via conduits.

Referring to fig. 1, a foam pump 303 is used to pump the foam. Upstream of the foam pump 303, two branches are provided: a foam concentrate suction branch 300a and a flushing branch 300b. The foam raw liquid suction branch 300a supplies foam raw liquid to the foam pump 303, and the flushing branch 300b supplies flushing water to the foam pump 303 when it is necessary to flush the respective components of the foam raw liquid supply path 300.

Referring to fig. 1, a foam suction valve 301 is located in the foam raw liquid suction branch 300a, and the foam suction valve 301 is configured to communicate with a foam raw liquid interface 306.

A flush inlet valve 302 is located in the flush branch 300b, the flush inlet valve 302 being configured to communicate with a flush water interface. A flush water inlet valve 302 is arranged in parallel with the foam imbibition valve 301.

A foam pump 303 is located downstream of the foam suction valve 301 and the flush inlet valve 302. If desired, one of the foam suction valve 301 and the flush inlet valve 302 is in a conducting state, and fluid can flow through the valve in the conducting state.

In order to accurately detect the pressure of the foam concentrate pumped by the foam pump 303, in some embodiments, the foam concentrate supply flow path 300 includes a check valve 304. The check valve 304 is used to make the foam in the piping of the foam pump 303 flow in one direction, placing a backflow.

In order to accurately detect the flow rate of the foam concentrate pumped by the foam pump 303, in some embodiments, the foam concentrate supply flow path 300 includes a foam flow meter 305. The foam flow meter 305 is used to detect the foam flow in the pipeline.

In some embodiments, foam aspirate valve 301, flush inlet valve 302, foam pump 303, foam flow meter 305, foam mix on-off valve 840 are all communicatively coupled to controller 850. The controller 850 is configured to control the respective operation states of the foam suction valve 301, the flushing water inlet valve 302, and the foam pump 303 according to the state parameters detected by the water flow meter 406, the second pressure gauge 602, the second switching valve 601, the foam mixture switching valve 840, the foam flow meter 305, the check valve 304, and the specific requirement of fire extinguishing.

With continued reference to fig. 1, the water supply flow path 400 is described below. According to the specific requirements of fire extinguishing, the fire-fighting foam foaming system can independently output water, dry foam and wet foam.

Referring to fig. 1, in some embodiments, the fire fighting foam foaming system further includes a water supply flow path 400. The water supply flow path 400 includes a filter 401, a water pump 402, a vacuum pump 403, and a check valve 404, and fluid communication between components requiring fluid communication is performed through piping. A water pump 402 is installed downstream of the filter 401; the vacuum pump 403 is communicated with a pipeline between the filter 401 and the water pump 402 to pump gas in the pipeline; a check valve 404 is installed downstream of the water pump 402.

The water supplied from the water supply line 400 may be used to produce foam mixture and fire foam, or may be used directly to extinguish a fire. In order to realize the above function switching, referring to fig. 1, in some embodiments, the fire fighting foam foaming system further includes a water spraying branch 500 and a foam spraying branch 600.

If it is required to use water as the fire extinguishing agent, the water spray branch 500 is in a conducting state and the foam spray branch 600 is disconnected, and at this time, the water supplied from the water supply flow path 400 does not flow to the first flow path 111 of the two-phase flow injection seat 110 of the fire fighting foam foaming device 100, but directly flows to the water spray branch 500 and is then output as the fire extinguishing agent.

If foam is required as the fire extinguishing agent, the water spray branch 500 is disconnected and the foam spray branch 600 is in a conducting state. At this time, the water supplied from the water supply path 400 is mixed with the foam raw liquid supplied from the foam raw liquid supply path 300 along the foam spraying branch 600, and then enters the first flow path 111 of the two-phase flow injection seat 110, and is acted together with the compressed gas supplied from the gas supply path 200, so as to obtain the fire fighting foam.

Specifically, the water spray branch 500 is arranged in parallel with the foam spray branch 600; one end of the water spray branch 500 is in fluid communication with the water supply flow path 400; the other end of the water spray branch 500 is connected in parallel with the first outlet pipe 150. The foam injection branch 600 communicates with the water supply flow path 400; the foam injection branch 600 is located between the water supply flow path 400 and the first flow path 111. The spray foam leg 600 is in fluid communication with both the water supply flow path 400 and the first flow path 111. Wherein the water supply flow path 400 is selectively in fluid communication with at least one of the water spray branch 500 and the foam spray branch 600.

Referring to fig. 1, in some embodiments, the fire fighting foam foaming system further comprises a first switching valve 501 and/or a second switching valve 601. The first switching valve 501 is installed in the water spray branch 500; the second switching valve 601 is installed in the foam injection branch 600. The first switching valve 501 is in a conducting state, and the water spraying branch 500 allows water to pass through; the first switching valve 501 is in an off state and the water spraying branch 500 does not allow water to pass through. The second switching valve 601 is in a conducting state, and the foam spraying branch 600 allows water to pass through; the second switching valve 601 is in an off state, and the foam spraying branch 600 does not allow water to pass through.

An external or fire-fighting vehicle enters the water supply flow path 400 through the water inlet pipe port 407, passes through the filter 401, and is pumped by the water pump 402 to flow downstream. A vacuum pump 403 and a vacuum gauge 405 are installed on the pipe between the water pump 402 and the filter 401 to evacuate the inside of the pipe when necessary. After passing through the water pump 402, the water passes through the check valve 404 and the water flow meter 406, and then the flow is switchably selected to the water spray branch 500 and the foam spray branch 600. When pressurized water supply is used, the vacuum pump 403 need not operate; when pumping a low water source, the vacuum pump 403 is used to pump a vacuum between the water pump 402 and the water intake pipe to effect the suction.

The first selection is as follows: when water flows to the foam injection branch 600, the second switching valve 601 is in the on state, the first switching valve 501 is in the off state, and all the water delivered by the water pump 402 enters the first flow path 111 of the two-phase flow injection seat 110 of the fire fighting foam foaming device 100 through the foam injection switching valve, and is initially mixed with the foam raw liquid delivered to the first flow path 111 of the two-phase flow injection seat 110 by the foam raw liquid supply flow path 300, thereby forming a foam mixed liquid. In order to control whether or not foaming is necessary more easily, a foam mixture switching valve 840 is provided at the inlet of the first flow path 111 of the two-phase flow inlet block 110, and the foam concentrate supply flow path 300 and the water supply flow path 400 are both located upstream of the foam mixture switching valve 840. The foam raw liquid supplied from the foam raw liquid supply passage 300 and the water supplied from the water supply passage 400 are merged at the foam liquid mixture switching valve 840. Foam mix on-off valve 840 is also communicatively coupled to controller 850 as described above, and controller 850 controls the parameters of the opening, closing, and opening of foam mix on-off valve 840.

In some embodiments, a second pressure gauge 602 is installed on the pipe between the upstream of the second switching valve 601 and the downstream of the water flow meter 406, and the second pressure gauge 602 detects the pressure of water in the pipe so that the water is mixed with the foam concentrate at a set pressure. The second pressure gauge 602 is in communication connection with the controller 850 described above, the parameter detected by the second pressure gauge 602 is sent to the controller 850, and the controller 850 controls the operating states of the water pump 402, the vacuum pump 403 and the foam spraying switch valve according to the parameter detected by the second pressure gauge 602.

The second option is: the water pumped by the water pump 402 does not flow through the fire fighting foam foaming device 100, but flows directly downstream of the fire fighting foam foaming device 100. At this time, the second switching valve 601 is off, and water cannot flow through the second switching valve 601. The first switching valve 501 is turned on, and water flows into the water spray branch 500 through the first switching valve 501, and finally flows to the sprayer 830 described later to be sprayed for fire extinguishing. The driving power of the water pump 402, the vacuum pump 403, the foam pump 303 and the air compressor 201 comes from a power device on the chassis of the fire engine, the water and the foam stock solution come from a water tank and a foam tank loaded on the chassis, the controller 850 calls a corresponding control program according to the input signals collected by various sensors and the operation instructions of an operator and according to the requirements of a fire extinguishing site and the different operation requirements of water spraying, wet foam spraying and dry foam spraying, the mixed composition of the water, the foam stock solution and the compressed gas is accurately prepared, and the water or foam spraying fire extinguishing with certain pressure and flow is realized.

For a large-flow compressed air foam system, because the flow of a fire-fighting pipeline is large, some large air masses which are not fully foamed may still exist after compressed gas is processed by the fire-fighting foam foaming device 100, and in addition, because the direction change or the diameter change in pipeline conveying is more, the formed composite fluid of foam (a large amount), foam mixed liquid (a small amount) and compressed gas (a small amount) can also overflow from the bubble flow to be integrated into large bubbles through the pipeline. In order to improve the fire extinguishing effect, the stream of bubbles delivered through the fire fighting foam foaming device 100 will be delivered to the fire fighting foam foamer 700 for re-fine division and mixed foaming. Referring to fig. 1, a fire fighting foam generator 700 is located downstream of the fire fighting foam generating device 100 and the water spray branch 500. The fire fighting foam maker 700 plays a role of foaming for the second time to improve the performance of the generated foam, so that the fire fighting requirement is more satisfied, and a better fire fighting effect is achieved.

There are multiple implementations of fire fighting foam foamer 700. Two specific implementations are described below.

Referring to fig. 11 and 12, the first implementation is: the fire fighting foam foamer 700 includes a body 701 and a baffle 702 mounted inside the body 701. In particular, the body 701 is configured as a body of revolution, in particular may be drum-shaped. The baffle 702 extends along the radial direction of the through hole 701a, and the most extensive surface of the baffle 702 is parallel to the cross section of the body 701.

Along the axial direction of the fire fighting foam generator 700, the body 701 has a through hole 701a penetrating through the axial direction thereof. The flow area of both end openings of the through hole 701a of the body 701 is smaller than the flow area of the middle portion of the body 701.

The baffle 702 is configured to be conical, and the cone angle of the baffle 702 is α. Specifically, α is 9 ° to 19 °, specifically 9 °, 12 °, 15 °, 17 °, 18 °, and 19 °. The angle of α varies depending on the number of baffle 702 distributions. The baffle 702 is arranged along the radial direction of the body 701, and one end of the baffle 702 is fixedly connected with the body 701, specifically, it may be welded or fixed by other fixing methods. The other end of the baffle 702 extends into the body 701 near the central axis. The size of one end of the baffle 702 is larger than that of the other end of the baffle 702, as shown in fig. 11, so that the connecting area of the baffle 702 and the body 701 is large, and the connection is more stable.

In some embodiments, the number of baffles 702 is 8 to 10. The baffles 702 are evenly distributed along the circumference of the body 701. The most extensive plane of the baffle 702 is parallel to the cross-section of the body 701, see fig. 11.

Referring to fig. 12, the diameter of the inlet of the through hole 701a of the body 701 is d1, the diameter of the body 701 corresponding to the position of the baffle 702 is d2, and the other ends of the plurality of baffles 702 are all located on the same circumference, which is d3. Wherein d2= (1.1 to 1.25) = d1. d3= (0.3 to 0.4) × d1. The thickness L3 of the baffle 702 is: l3=15mm to 30mm, and the width L4 of the baffle 702 is: l4=15mm ~ 30mm, adopt above-mentioned parameter range, reduce pipeline pressure loss, effectively broken the big foam that the foam that comes from fire control foam foaming device 100 to carry formed in transportation process, improved the foaming quality of fire control foam foaming system, can obtain more even, the better foam of fire extinguishing performance.

The fire-fighting foam foaming device 700 has an axial length L2, and L2 is not less than d1. The flow area (also called as flow area) of the fire-fighting foam foaming device 700 after passing through the baffle 702 is 0.85-1 times of that of the fire-fighting foam foaming device 700 at the inlet, and finally the fluid appearance speed V before entering the fire-fighting foam foaming device 700 is realized _2I Is the fluid apparent velocity V at the inlet of the fire-fighting foam foaming device 700 ₂ 0.6-0.8 times of the apparent velocity V of the fluid after passing through the mixing chamber conical baffle 702 _2O Is the fluid apparent velocity V at the inlet of the fire-fighting foam foaming device 700 ₂ 1.1 to 1.3 times.

The fire-fighting foam foaming device 700 adopts the implementation mode, so that the pressure loss of the mixed through flow is reduced, and the foam can be promoted to be foamed again in the conveying process; the fire-fighting foam foaming device 700 is compact in structure and small in occupied space, and each baffle 702 is tapered along the radial direction of the body 701, so that impact pressure loss during foam overflowing is reduced; on the other hand, the large bubbles which run on the wall of the circular pipe and overflow due to the liquid throttling, the plug flow and the like can be crushed again, and a plurality of turbulent vortices distributed from the wall of the circular pipe to the center of the pipeline can be formed at the rear side, namely the downstream side, of the baffle 702, so that the gas-liquid two-phase flow is promoted to be uniformly dispersed again, and finally, finer and uniform high-quality foam is formed, so that the fire extinguishing effect is improved.

The technical scheme is suitable for a scene needing large-flow compressed air foam, the fire-fighting foam foaming system comprises a fire-fighting foam foaming device 100 and a fire-fighting foam foaming device 700 which are connected in series, the fire-fighting foam foaming device 100 is used for mixing and foaming compressed gas and foam mixed liquid injected by gas-liquid two-phase flow, namely first-stage foaming is realized, the fire-fighting foam foaming device 700 realizes second-stage foaming, after the fire-fighting foam foaming device 100 is processed by the fire-fighting foam foaming device 700, large gas clusters which still exist and are not fully dispersed into the foam mixed liquid and large integrated bubbles which overflow from the gas bubbles due to the turning or reducing of a certain conveying distance are subjected to secondary segmentation and mixed foaming, namely secondary foaming is realized. The test and verification of the foam mixed liquid with the flow rate of 100-200L/s show that the technical scheme has satisfactory foaming effect within the foaming multiple of 3-15.

Returning to fig. 1, in some embodiments, the fire fighting foam foaming system further includes a delivery tube 810, the delivery tube 810 being in fluid communication with the fire fighting foam foamer 700, the delivery tube 810 being located downstream of the fire fighting foam foamer 700.

The foam generated by the two-stage foaming is transported out through the transport pipe 810. Delivery tube 810 may be mounted in sections to swivel 820 to achieve the folding of the travel state and the unfolding spray requirements of the operational state of the on-board piping system.

In some embodiments, the number of delivery pipes 810 includes a plurality, two adjacent delivery pipes 810 are in fluid communication with each other, and at least one delivery pipe 810 is mounted to the swivel 820 to adjust the direction of the fire fighting foam. The delivery pipe 810 can be a hard pipe or a soft pipe.

Referring to fig. 1, in some embodiments, the fire fighting foam foaming system further comprises a sprayer 830, such as a fire monitor in particular, sprayer 830. The ejector 830 is installed at the downstream end of the duct 810, and the foam is finally transferred from the duct 810 to the ejector 830 and then ejected for extinguishing fire. The distance between the ejector 830 and the fire fighting foam generator 700 is greater than 5 to 10 times the maximum diameter of the pipe between the fire fighting foam generator 700 and the ejector 830. Fire fighting foam foamer 700 and delivery line foam between the device and eductor 830 is indicative of fourth speed V _F2 6m/s to 12m/s, so that the ejector 830 can spray uniform fire-fighting foam with good quality.

Referring to fig. 1, in some embodiments, the length of the pipeline between the fire fighting foam foaming device 100 and the fire fighting foam generator 700 is 10 to 20 times or more greater than the maximum diameter of the pipeline, so as to facilitate the stabilization of foam generation.

In order to reduce the pressure loss of the pipeline and improve the foaming quality and form uniform bubble flow, the fire-fighting foam foaming system adopts the following parameters: foam mixed liquid conveying pipeline representation first flow velocity V _MI Is 6 to 8m/s. The compressed gas conveying pipeline represents a second flow velocity V _G 8-15 m/s; third speed V of foam appearance in pipeline 810 between fire fighting foam foaming device 100 and fire fighting foam foaming machine 700 _F1 Is 5 to 10m/s. The inlet apparent velocity of the fire fighting foam foamer 700 is the same as the outlet apparent velocity thereof, and is V _F1 And is 5 to 10m/s. Apparent fourth velocity V of pipeline-conveyed foam between fire fighting foam foamer 700 and eductor 830 _F2 Is 6 to 12m/s.

Above-mentioned technical scheme is adapted to large-traffic compressed air foam system, and the foaming quality is high, and pipeline pressure loss is little, and foaming device compact structure is exquisite, the space occupy-place is little to and use maintenance convenience.

Referring to fig. 13, an embodiment of the present invention provides a fire fighting foam foaming method, which is implemented by using a fire fighting foam foaming system provided in any technical solution of the present invention, and the contents not described in this embodiment may refer to the contents of the above embodiments. The fire-fighting foam foaming method comprises the following steps:

step S100, when the foam extinguishing agent needs to be sprayed, the foam extinguishing agent is sprayed according to a set first flow speed V _Ml The foam mixture is supplied to the first inlet pipe 140 of the fire fighting foam foaming device 100. In some embodiments, V _Ml Is 6 to 8m/s.

Step S200, according to the set second flow velocity V _G Compressed gas is delivered to the second flow path 112 of the two-phase flow injection seat 110 of the fire fighting foam foaming device 100. In some embodiments, the second flow rate V _G Is 8 to 15m/s. The step S100 is performed first, and then the step S200 is performed, so that the injection initial jet flow is more stable.

In some embodiments, the fire fighting foam foaming method further comprisesThe following step S300: according to a set third flow velocity V _F1 The fluid output from the fire fighting foam foaming device 100 is delivered to the fire fighting foam foamer 700. The foam expression speed of the conveying pipe 810 between the two-stage foaming devices is a third flow speed V _F1 . In some embodiments, V _F1 Is 5m/s to 10m/s.

In some embodiments, the fire fighting foam foaming method further comprises the following step S400: according to the set fourth flow velocity V _F2 The fluid output by fire fighting foam foamer 700 is delivered to eductor 830. In some embodiments, V _F2 Is 6 to 12m/s.

According to the technical scheme, proper foaming parameters are adopted, so that the pressure loss of a pipeline can be effectively reduced, the foaming quality is improved, an even bubble flow is formed, and the device is particularly suitable for a high-flow compressed air foaming system.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientations and positional relationships indicated in the drawings, which are based on the orientation or positional relationship shown in the drawings, and are used for convenience of description and simplicity of description only, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the scope of the present invention.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: it is to be understood that modifications may be made to the technical solutions described in the foregoing embodiments, or equivalents may be substituted for some of the technical features thereof, but such modifications or substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

In the description of the present invention, it is to be understood that the terms "central", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be considered as limiting the scope of the present invention.

Claims

1. A fire fighting foam foamer comprising:

a body (701) comprising a through hole (701 a); the flow area of the middle region of the through hole (701 a) is larger than the flow areas of the two ends of the through hole (701 a); and

and a baffle plate (702) mounted in the middle region of the through hole (701 a).

2. Fire fighting foam foamer according to claim 1, characterized in that the body (701) is configured as a body of revolution, the length direction of the baffle (702) being along the radial direction of the through hole (701 a), the maximum extension of the baffle (702) being parallel to the cross section of the body (701).

3. A fire fighting foam foamer as recited in claim 1, characterized in that one end of said baffle (702) is of a larger size than the other end of said baffle (702); one end of the baffle (702) is fixedly connected with the inner wall of the through hole (701 a), and the other end of the baffle (702) faces to the central axis of the through hole (701 a).

4. A fire fighting foam foamer as defined in claim 3, characterized in that said baffle (702) is constructed conical and the cone angle of said baffle (702) is between 9 ° and 19 °.

5. A fire fighting foam foamer according to claim 1, characterized in that the number of said baffles (702) is plural, a plurality of said baffles (702) being arranged dispersed along the circumference of said through hole (701 a).

6. A fire fighting foam foamer as defined in claim 1, characterized in that the through hole (701 a) has an axial length which is greater than the diameter of the opening at both ends of the through hole (701 a).

7. A fire fighting foam foamer according to claim 1, characterized in that the maximum diameter of said through hole (701 a) is 1.1-1.25 times the diameter of the both end openings of said through hole (701 a).

8. A fire fighting foam foaming system, comprising:

a fire fighting foam foaming device (100) configured to foam the foam mixture, the compressed gas, into fire fighting foam; and

the fire fighting foam foamer (700) of any one of claims 1 to 7, said fire fighting foam foamer (700) being installed downstream of said fire fighting foam foaming device (100) and in series therewith for the secondary foaming of the fire fighting foam delivered by said fire fighting foam foaming device (100).

9. A fire fighting foam foaming system according to claim 8, characterized in that the fire fighting foam foaming device (100) comprises:

a two-phase flow injection seat (110) including a first flow path (111) and a second flow path (112) that are independent of each other;

the air nozzle assembly (120) comprises an air inlet hole (121), an air inlet hole (122), a first air outlet hole (123) and a flow guide part (124); the liquid inlet hole (121) is in fluid communication with the first flow path (111), and the liquid inlet hole (121) is located downstream of the first flow path (111); the intake aperture (122) being in fluid communication with the second flow path (112) and being located downstream of the second flow path (112); and

a foam mixing chamber (130) downstream of the first flow path (111) and the second flow path (112) and in fluid communication with both the first flow path (111) and the second flow path (112); the first air outlet hole (123) and the flow guide part (124) extend into the foam mixing chamber (130); the first air outlet hole (123) and the flow guide portion (124) are configured such that the air flow outputted via the air nozzle assembly (120) flows to different positions in a radial direction of the foam mixing chamber (130).

10. A fire fighting foam foaming system according to claim 9, wherein the deflector (124) comprises:

a second outlet hole (124') located at a different position in a radial direction of the foam mixing chamber (130) from the first outlet hole (123).

11. The fire fighting foam foaming system of claim 9, wherein the air nozzle assembly (120) comprises:

a mounting plate (125) attached and fixed to the two-phase flow injection seat (110); the mounting plate (125) is provided with a liquid inlet hole (121) which is in fluid communication with the first flow path (111) of the two-phase flow injection seat (110) and the air inlet hole (122) which is in fluid communication with the second flow path (112);

an axial tube (126) mounted to the mounting plate (125) on a side thereof remote from the two-phase flow injection seat (110); the axis of the axial tube (126) is parallel to the central axis of the two-phase flow injection seat (110); the axial tube (126) being in fluid communication with the air intake hole (122) of the mounting plate (125); and

a radial tube (127), a central axis of the radial tube (127) intersecting a central axis of the axial tube (126), one end of the radial tube (127) being in fluid communication with the axial tube (126), the other end of the radial tube (127) being located on a side of the axial tube (126) facing the central axis of the two-phase flow injection seat (110).

12. Fire fighting foam foaming system according to claim 11, wherein the number of the axial pipes (126) is a plurality, the plurality of axial pipes (126) being distributed around the circumference of the mounting plate (125).

13. The fire fighting foam foaming system of claim 11 wherein the other end of the axial tube (126) is distal from the two-phase flow injection seat (110); the other end of the axial pipe (126) is used as the first air outlet hole (123) and is open; the other end of the axial tube (126) is opposite to the inner wall of the foam mixing chamber (130).

14. A fire fighting foam foaming system according to claim 13, wherein the other end of the radial pipe (127) is remote from the axial pipe (126), the other end of the radial pipe (127) being closed; the side wall of the radial pipe (127) close to the other end of the axial pipe (126) is provided with a second air outlet hole (124');

the axial direction of the second air outlet (124 ') is parallel to the central axis of the two-phase flow injection seat (110), or the axial direction of the second air outlet (124') intersects the central axis of the two-phase flow injection seat (110), and the included angle is smaller than 90 degrees.

15. A fire fighting foam foaming system according to claim 9, wherein the deflector (124) comprises:

a baffle (124 ") positioned adjacent to the first outlet aperture (123); the deflector (124 ") is configured to deflect a portion of the air stream output via the first outlet aperture (123) to a position proximate a central axis of the foam mixing chamber (130).

16. The fire fighting foam foaming system of claim 15, wherein the air nozzle assembly (120) further comprises:

a mounting plate (125) attached and fixed to the two-phase flow injection seat (110); the mounting plate (125) is provided with the air inlet hole (122) which is in fluid communication with the second flow path (112) of the two-phase flow injection seat (110); and

an axial tube (126) mounted to the mounting plate (125) on a side thereof remote from the two-phase flow injection seat (110); the axial line of the axial pipe (126) is parallel to the central axis of the two-phase flow injection seat (110); the axial tube (126) being in fluid communication with the air intake hole (122) of the mounting plate (125);

wherein the baffle (124 ") is fixedly connected to the axial tube (126), the baffle (124") being configured without holes; the baffle (124 ") is configured to create a negative pressure region on a side of itself remote from the mounting plate (125) such that a portion of the airflow output by the axial tube (126) flows to the negative pressure region.

17. The fire fighting foam foaming system according to claim 16, wherein the first flow path (111) is located on a central axis of the two-phase flow injection seat (110); the second flow path (112) is located outside the first flow path (111) in a radial direction of the two-phase flow injection seat (110).

18. A fire fighting foam foaming system according to any one of claims 8 to 17, further comprising:

a first inlet pipe (140), the first flow path (111) being downstream of the first inlet pipe (140) and in fluid communication with the first inlet pipe (140); and

a first outlet tube (150) mounted downstream of the foam mixing chamber (130).

19. Fire fighting foam foaming system according to claim 9, characterized in that the inner wall of the foam mixing chamber (130) is conically configured; the flow area of the inlet of the foam mixing chamber (130) is larger than the flow area of the outlet of the foam mixing chamber (130).

20. The fire fighting foam foaming system of claim 9, further comprising:

a gas supply flow path (200) located upstream of the second flow path (112) of the two-phase flow injection seat (110) to supply gas to the two-phase flow injection seat (110);

a foam concentrate supply passage (300) located upstream of the first passage (111) of the two-phase flow injection seat (110) to supply a foam concentrate to the two-phase flow injection seat (110); and

a water supply flow path (400) also located upstream of the first flow path (111) of the two-phase flow injection seat (110) to supply water to the two-phase flow injection seat (110).

21. The fire fighting foam foaming system of claim 20, further comprising:

a water spray branch (500) arranged in parallel with the fire fighting foam foaming device (100); one end of the water spray branch (500) is in fluid communication with the water supply flow path (400); the other end of the water spraying branch (500) is connected with the first outlet pipe (150) in parallel; and

a foam spray branch (600) communicating with the water supply flow path (400); the foam spraying branch (600) is positioned between the water supply flow path (400) and the first flow path (111) and is in fluid communication with both the water supply flow path (400) and the first flow path (111);

wherein the water supply flow path (400) is selectively in fluid communication with at least one of the water spray branch (500) and the foam spray branch (600).

22. The fire fighting foam foaming system of claim 8, further comprising:

a delivery tube (810) in fluid communication with the fire fighting foam foamer (700), the delivery tube (810) being located downstream of the fire fighting foam foamer (700); and

and a rotating body (820) connected to the delivery pipe (810).

23. The fire fighting foam foaming system of claim 22, further comprising:

an ejector (830) mounted downstream of the delivery tube (810); the distance between the ejector (830) and the fire-fighting foam generator (700) is 5 to 10 times larger than the maximum diameter of a pipeline between the fire-fighting foam generator (700) and the ejector (830).

24. The fire fighting foam foaming system according to claim 8, wherein the length of the pipeline between the fire fighting foam foaming device (100) and the fire fighting foam foamer (700) is 10 to 20 times or more the maximum diameter of the pipeline.

25. A fire fighting foam foaming method, which is realized by the fire fighting foam foaming system of any one of claims 8 to 24, and comprises the following steps:

when the foam extinguishing agent needs to be sprayed, the first flow rate V is set _Ml Delivering a foam mixture to a first inlet pipe (140) of the fire fighting foam foaming device (100);

according to the set second flow velocity V _G Delivering compressed gas to a second flow path (112) of a two-phase flow injection seat (110) of the fire fighting foam foaming device (100);

according to a set third flow velocity V _F1 Delivering the fluid output by the fire fighting foam foaming device (100) to a fire fighting foam foaming machine (700).

26. The fire fighting foam expansion method of claim 25, wherein V is _Ml 6-8 m/s; and/or

The V is _G 8-15 m/s; and/or

The V is _F1 5-10 m/s; and/or

The flow velocity of foam mixed liquid injected into the inlet of the foam mixing chamber (130) of the fire-fighting foam foaming device (100) is V _1I ，V _1I Is 2m/s to 5m/s; and/or

Foam mixing of the fire fighting foam foaming device (100)The inlet of the chamber (130) is filled with compressed gas at an apparent flow rate V _1G ，V _1G Is 10m/s to 20m/s; and/or

The flow rate of the foam outflow representation at the outlet of the foam mixing chamber (130) of the fire-fighting foam foaming device (100) is V _1O ，V _1O Is 4m/s to 8m/s.

27. A fire fighting foam foaming method according to claim 25, further comprising the steps of:

according to the set fourth flow velocity V _F2 Delivering fluid output by the fire fighting foam foamer (700) to an eductor (830).

28. A fire fighting foam foaming method according to claim 27, wherein V is _F2 Is 6 to 12m/s.