CN112345688A - Device and method for testing fire extinguishing efficiency of superfine dry powder extinguishing agent - Google Patents
Device and method for testing fire extinguishing efficiency of superfine dry powder extinguishing agent Download PDFInfo
- Publication number
- CN112345688A CN112345688A CN202011288170.6A CN202011288170A CN112345688A CN 112345688 A CN112345688 A CN 112345688A CN 202011288170 A CN202011288170 A CN 202011288170A CN 112345688 A CN112345688 A CN 112345688A
- Authority
- CN
- China
- Prior art keywords
- aerosol
- fire extinguishing
- concentration
- laser
- powder
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000000843 powder Substances 0.000 title claims abstract description 71
- 238000012360 testing method Methods 0.000 title claims abstract description 45
- 239000003795 chemical substances by application Substances 0.000 title claims abstract description 43
- 238000000034 method Methods 0.000 title claims abstract description 13
- 239000000443 aerosol Substances 0.000 claims abstract description 82
- 238000005259 measurement Methods 0.000 claims abstract description 34
- 239000002912 waste gas Substances 0.000 claims abstract description 8
- 238000012545 processing Methods 0.000 claims abstract description 7
- 239000008275 solid aerosol Substances 0.000 claims abstract description 5
- 239000007789 gas Substances 0.000 claims description 31
- 239000003921 oil Substances 0.000 claims description 27
- 230000005484 gravity Effects 0.000 claims description 22
- 238000002485 combustion reaction Methods 0.000 claims description 21
- 238000009792 diffusion process Methods 0.000 claims description 18
- 239000002245 particle Substances 0.000 claims description 16
- 239000002184 metal Substances 0.000 claims description 14
- 239000000446 fuel Substances 0.000 claims description 13
- 238000002834 transmittance Methods 0.000 claims description 8
- 238000007906 compression Methods 0.000 claims description 7
- 230000006835 compression Effects 0.000 claims description 7
- 239000007788 liquid Substances 0.000 claims description 7
- 238000002474 experimental method Methods 0.000 claims description 6
- 230000001133 acceleration Effects 0.000 claims description 4
- 239000006185 dispersion Substances 0.000 claims description 4
- 239000000295 fuel oil Substances 0.000 claims description 4
- 238000010008 shearing Methods 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 230000008859 change Effects 0.000 claims description 3
- 230000010349 pulsation Effects 0.000 claims description 3
- 238000005303 weighing Methods 0.000 claims description 3
- 230000008569 process Effects 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims 1
- 239000000428 dust Substances 0.000 abstract description 3
- 238000013461 design Methods 0.000 abstract 1
- IMNFDUFMRHMDMM-UHFFFAOYSA-N N-Heptane Chemical compound CCCCCCC IMNFDUFMRHMDMM-UHFFFAOYSA-N 0.000 description 9
- 229920004449 Halon® Polymers 0.000 description 5
- PXBRQCKWGAHEHS-UHFFFAOYSA-N dichlorodifluoromethane Chemical compound FC(F)(Cl)Cl PXBRQCKWGAHEHS-UHFFFAOYSA-N 0.000 description 5
- 239000000126 substance Substances 0.000 description 4
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 3
- 239000002283 diesel fuel Substances 0.000 description 3
- 239000003502 gasoline Substances 0.000 description 3
- 239000003350 kerosene Substances 0.000 description 3
- 230000001105 regulatory effect Effects 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 241000178343 Butea superba Species 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000008033 biological extinction Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000002153 concerted effect Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000013022 formulation composition Substances 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 239000005437 stratosphere Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N31/00—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods
- G01N31/12—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods using combustion
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
- G01N15/075—Investigating concentration of particle suspensions by optical means
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Physics & Mathematics (AREA)
- Physics & Mathematics (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Dispersion Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Combustion & Propulsion (AREA)
- Molecular Biology (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
- Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
Abstract
The invention discloses a device and a method for testing the fire extinguishing efficiency of a superfine dry powder fire extinguishing agent. The device comprises an air inlet system, an aerosol generating system, a device supporting system, a cup type combustor, a laser measuring system, a waste gas collecting and processing system and a calibration system. The method comprises the steps of calibrating the laser system and measuring the laser system. Compared with the prior art, the device can form stable, even, dispersed solid aerosol in the cup type combustor, has solved the big problem of critical concentration measurement error of putting out a fire that the dust distributes inhomogeneous and leads to. The method can be used for evaluating the fire extinguishing performance of the existing superfine dry powder fire extinguishing agent and can also be used for optimizing the formula design of novel superfine powder.
Description
Technical Field
The invention relates to the field of testing of fire extinguishing efficiency of superfine dry powder fire extinguishing agents, in particular to a device and a method for testing the fire extinguishing efficiency of superfine dry powder fire extinguishing agents.
Background
The Halon fire extinguishing agent is used as a main fire extinguishing product for fire fighting, has the characteristics of high fire extinguishing speed, high efficiency, no electricity conduction, no residue after fire extinguishing and the like, and is widely applied to civil airliners, electronic computer rooms, cultural relic protection units, large ships and naval vessels. However, since the 70's of the 20 th century, scientists discovered that ozone in the earth's ozone layer was continuously decreasing and that halon fire extinguishing agents, which are used extensively in the fire fighting industry, were long-lived in the atmosphere after release. When the residual substances in the atmosphere drift to the stratosphere, the residual substances are subjected to ultraviolet UV-C irradiation, and are decomposed to generate Cl or Br radicals, so that the residual substances participate in the consumption of the ozone layer. Based on this, in 1987, the United nations environmental planning agency (UNEP) made a Montreal concerted book on ozone-destroying substances. Halon fire extinguishants have been banned so far in developed countries, and are also incorporated into obsolete materials in other developing countries.
The superfine dry powder extinguishing agent belongs to one of solid aerosol extinguishing agents, and refers to D of particle size90The fire extinguishing agent (90% grain diameter) is less than or equal to 20um, and can be used as a good Halon substitute. When fire is extinguished, the fire-extinguishing agent can be diffused to a fire area in a very short time, bypasses barriers, remains in a fire space for a long residence time, and has a long protection time for a protection space. The superfine dry powder particles have small particle size, large specific surface area, high fire extinguishing efficiency and low concentration. The fire extinguishing powder can be used for extinguishing A/B mixed fire, B and C fire in a full or semi-closed space, has the fire extinguishing efficiency 5-9 times higher than that of common dry powder, and is 2-3 times higher than that of a Halon fire extinguishing agent.
However, depending on the formulation composition and particle size of different superfine dry powder extinguishing agents, the fire extinguishing performance of the products from different manufacturers may cause differences, i.e., the minimum extinguishing efficiency of each manufacturer is different. Among the current standards of powder extinguishing agent products, a fire model close to the actual fire scene scale is adopted to qualitatively evaluate whether the fire extinguishing performance of the existing superfine powder extinguishing agent or fire extinguishing system can meet the relevant requirements, such as GB4066-2004 'powder extinguishing agent' adopting a local fire extinguishing test model of a portable fire extinguisher (3kg) extinguishing oil pan fire, GA 578-3The test model of total flooding fire extinguishing in the fire extinguishing room. Because of lack of quantitative experiments, the critical fire extinguishing parameters of the superfine dry powder fire extinguishing agent cannot be given, which brings difficulties to the research and development of the formula of the superfine dry powder fire extinguishing agent and the industrial application of the fire extinguishing technology.
In order to evaluate the fire extinguishing performance of superfine dry powder fire extinguishing agents with different raw materials and particle sizes and accurately test the critical fire extinguishing parameters of different superfine dry powder fire extinguishing agents, a scientific and effective fire extinguishing efficiency testing device for the superfine dry powder fire extinguishing agents is urgently needed. In the existing technology, researchers of Tianjin fire research institute propose a method for testing the fire extinguishing performance of superfine dry powder fire extinguishing agents (CN203376300U fire extinguishing performance testing device), which adopts a spiral propelling mode to convey powder, and mixes the powder with dry air to form aerosol for fire extinguishing test. However, the non-uniformity of the aerosol formed can lead to difficulties in measuring the critical extinguishing concentration of the powder, most notably the critical extinguishing characteristics of the flame.
Based on the device, the invention provides a novel critical extinguishing efficiency testing device for the superfine dry powder extinguishing agent.
Disclosure of Invention
The invention provides a device and a method for testing the fire extinguishing efficiency of an ultrafine dry powder fire extinguishing agent, aiming at accurately testing the critical fire extinguishing concentration of the ultrafine dry powder fire extinguishing agent with different raw materials and particle size distribution.
The technical scheme adopted by the invention is that the device for testing the fire extinguishing efficiency of the superfine dry powder fire extinguishing agent comprises: the device comprises an air inlet system, an aerosol generating system, a device supporting system, a laser measuring system, a cup type burner, a waste gas collecting and processing system and a calibration system (7).
The air inlet system sends dry and clean compressed air to the aerosol generating system to form stable aerosol which is sent to the cup-type combustor. The concentration of the generated aerosol can be accurately controlled by adjusting the air flow of the air inlet system and the powder feeding rate of the aerosol generating system. By adjusting the aerosol concentration, the flame of the cup-type burner is separated from the bottom of the stable flame gradually to generate flame pulsation, namely the critical extinguishing phenomenon of the flame, and the concentration is detected by using a laser measurement system, namely the corresponding critical extinguishing concentration of the extinguishing agent.
The air intake system comprises an air compression pump, a water and oil removing filter and an air flow controller.
The aerosol generating system uniformly mixes air and superfine powder to form stable polydisperse distributed solid aerosol;
the device support system is used for supporting and fixing the main body testing device.
The laser measurement system can measure the change of the powder concentration in real time. The laser measuring system comprises a laser transmitting end and a laser receiving end. Prior to use, the laser measurement system is calibrated in a calibration system. The calibration system comprises an air source part, an aerosol generator, a balance, a calibration section, a data acquisition system, a test pipeline, a powder capture system and an air pipe. The gas supply section includes a controller operable to regulate the flow of gas Q, which can be regulated. The aerosol generator thoroughly mixes the powder sample with the gas stream to form a polydisperse aerosol. The aerosol generator is conveyed to the rotary brush through the piston, the rotary brush can accurately convey a certain amount of samples to the diffusion head, the air flow is accelerated at the diffusion head through the acceleration of the nozzle, the high-speed air flow provides necessary turbulence and shearing force for the sufficient dispersion of the powder, the agglomerated particles are finally dispersed and output, and the output aerosol is in polydisperse distribution. The generated aerosol enters a test pipeline, and is uniformly diffused for a certain distance, and finally, the particle speeds of different particle sizes reach stability and move downwards at a constant speed. The balance measures the mass loss of the powder in the aerosol generator in real time and carries out data acquisition processing through the data acquisition system.
The cup type combustor comprises a gravity oil supply device, a connector, a combustion cup, an aerosol connecting port, a metal diffusion section, an observation section, a metal connecting cylinder, a rectifying screen and an experiment measurement section.
Wherein, the gravity oil supply device is connected with the combustion cup through a pipeline, the constant of the liquid level of the combustion cup is ensured by utilizing the principle of a communicating vessel in the combustion process, and preferably, the ratio of the surface area S1 of the gravity oil supply device to the surface area S2 of the combustion cup is S1: s2> 100; the connecting port not only supports the connection with the gravity oil supply device, but also can be connected with a combustible gas pipeline; aerosol generated by the aerosol generating system passes through the aerosol connecting port, the metal diffusion section, the observation section, the metal connecting cylinder and the rectifying screen to reach the experimental measurement section;
the exhaust gas treatment system is used for collecting generated aerosol.
A method for testing the fire extinguishing efficiency of an ultrafine dry powder fire extinguishing agent comprises the following steps:
step S1), placing the laser measurement system in a calibration system, adjusting the air quantity of an air source to be Q, setting the feeding speed of the aerosol generator, and weighing the mass loss M' of the aerosol generation system in real time by using a balance. And calculating to obtain the concentration C in the cavity as M'/Q.
Step S2), before the measurement, the initial signal I of the laser measuring system is determined0. Collecting signals of a laser measurement system in real time, selecting an average value I 'of a stable section, and obtaining the light transmittance T ═ I'/I0. Plotting the square T of the transmittance2And fitting the curve to obtain a corresponding fitting formula f (x).
Step S3), adding fuel oil (such as n-heptane, gasoline, diesel oil, aviation kerosene and the like) on the gravity oil supply device, and adjusting the position of the gravity oil supply device to ensure that the distance between the liquid level of the fuel in the combustion cup and the top of the cup is within 5-10 mm. And opening the waste gas collecting device and the air compression pump, adjusting the flow of air to be 10L/min, igniting the fuel, and pre-burning for 60 s. The fuel tube can also be connected to carry out ignition test on the combustible gas.
Step S4), starting the aerosol generator, gradually adjusting the powder feeding rate from slow to fast, recording a concentration value q measured by a laser measurement system when the root of the flame is suspended from a stable state and continuously pulsates, and repeatedly carrying out the experiment for many times to finally obtain the critical fire extinguishing concentration of the specified superfine dry powder fire extinguishing agent:
wherein q' represents the average of the measured concentration values, qiRepresents the concentration value measured at the i-th time, and n represents the total number of measurements.
Compared with the prior art, the invention has the advantages that:
(1) the invention adopts the dust aerosol generator, and the inlet end of the cup type combustor is provided with the diffusion section and the screen, thereby solving the problem of non-uniformity of the distribution of the superfine dry powder extinguishing agent in the cup type combustor;
(2) the calibration system is designed by utilizing the free settling characteristic of the powder, the test environment is uniform, and the calibration error is low;
(3) the device can accurately observe the critical characteristic of flame extinction and obtain the accurate critical extinguishing concentration of the superfine dry powder extinguishing agent.
Drawings
FIG. 1 is a schematic view of a device for testing the extinguishing efficiency of an ultrafine dry powder extinguishing agent according to the present invention;
FIG. 2 is a schematic view of an air induction system;
FIG. 3 is a schematic view of a cup burner configuration;
FIG. 4 is a calibration system;
FIG. 5 is a schematic view of the dust aerosol diffusion in a test chamber for one embodiment of a calibration test;
FIG. 6 is a graph of photo-electric signal over time for one embodiment of a calibration test;
FIG. 7 is a real-time plot of mass over time for a calibration test;
FIG. 8 is a calibration fit curve.
The figures in the drawing are denoted by the following meanings: 1 is an air inlet system, 2 is an aerosol generating system, 3 is a device supporting system, 4 is a laser measuring system, 5 is a cup-type burner, 6 is a waste gas collecting and processing system, and 7 is a calibration system. Wherein 11 is an air compression pump, 12 is a water and oil removing filter, and 13 is an air flow controller; 51 is a gravity oil supply device, 52 is a connecting port, 53 is a combustion cup, 54 is an aerosol connecting port, 55 is a metal diffusion section, 56 is an observation section, 57 is a metal connecting cylinder, 58 is a rectifying screen, 59 is an experimental measurement section, 71 is an air source part, 72 is an aerosol generator, 73 is a balance, 74 is a calibration section, 75 is a data acquisition system, 76 is a test pipeline, 77 is a powder capture system, and 78 is an air pipe.
Detailed Description
The following examples are further illustrative of the present invention as to the technical content of the present invention, but the essence of the present invention is not limited to the following examples, and one of ordinary skill in the art can and should understand that any simple changes or substitutions based on the essence of the present invention should fall within the protection scope of the present invention.
As shown in figure 1, the invention relates to a device for testing the fire extinguishing efficiency of an ultrafine dry powder fire extinguishing agent, which comprises: the device comprises an air inlet system 1, an aerosol generating system 2, a device supporting system 3, a laser measuring system 4, a cup type combustor 5, a waste gas collecting and processing system 6 and a calibration system 7.
The air inlet system 1 sends dry and clean compressed air to the aerosol generating system 2 to form stable aerosol which is sent to the cup type combustor 5. By adjusting the air flow of the air inlet system 1 and the powder feeding rate of the aerosol generating system 2, the concentration of generated aerosol can be accurately controlled. By adjusting the aerosol concentration, the flame of the cup burner is separated from the bottom of the stable flame gradually to generate flame pulsation, namely the critical extinguishing phenomenon of the flame, and the laser measuring system 4 is used for detecting the concentration, namely the corresponding critical extinguishing concentration of the extinguishing agent.
The air intake system 1 includes an air compressor pump 11, a water and oil removing filter 12, and an air flow controller 13.
The aerosol generating system 2 is used for uniformly mixing air and superfine powder to form stable polydisperse distributed solid aerosol;
the device support system 3 is used to support a stationary subject testing device.
The laser measurement system 4 can measure the change of the powder concentration in real time. The laser measuring system 4 includes a transmitting end and a receiving end of laser light. Before use, the laser measurement system is calibrated in a calibration system 7. Calibration system 7 includes gas supply portion 71, aerosol generator 72, balance 73, calibration section 74, data acquisition system 75, test tube 76, powder capture system 77, gas line 78. The gas supply section 71 includes a controller operable to regulate the flow of gas Q, which can be regulated. The aerosol generator 72 thoroughly mixes the powder sample with the gas stream to form a polydisperse aerosol. The aerosol generator is conveyed to the rotary brush through the piston, the rotary brush can accurately convey a certain amount of samples to the diffusion head, the air flow is accelerated at the diffusion head through the acceleration of the nozzle, the high-speed air flow provides necessary turbulence and shearing force for the sufficient dispersion of the powder, the agglomerated particles are finally dispersed and output, and the output aerosol is in polydisperse distribution. The aerosol generated enters the test tube 76 and is uniformly dispersed for a distance, and finally, the particles with different particle sizes reach a stable speed and move downwards at a constant speed. The balance 73 measures the mass loss of the powder in the aerosol generator in real time and performs data acquisition processing through the data acquisition system 75.
The cup type burner 5 comprises a gravity oil supply device 51, a connecting port 52, a combustion cup 53, an aerosol connecting port 54, a metal diffusion section 55, an observation section 56, a metal connecting cylinder 57, a rectifying screen 58 and an experimental measurement section 59.
Wherein, the gravity oil supply device 51 is connected with the combustion cup 53 through a pipeline, and the constant liquid level of the combustion cup 53 is ensured by using the principle of communicating vessels during the combustion process, preferably, the ratio between the surface area S1 of the gravity oil supply device 51 and the surface area S2 of the combustion cup, namely S1: s2> 100; the connecting port 52 is not only connected with the gravity oil supply device 51, but also connected with a combustible gas pipeline; the aerosol generated by the aerosol generating system 2 passes through the aerosol connecting port 54, the metal diffusion section 55, the observation section 56, the metal connecting cylinder 57 and the rectifying screen 58 to reach the experimental measurement section 59;
the exhaust gas treatment system 6 is used to collect the generated aerosol.
A method for testing the fire extinguishing efficiency of an ultrafine dry powder fire extinguishing agent comprises the following steps:
step S1), placing the laser testing system in a calibration system, adjusting the air quantity of an air source to be Q, setting the feeding speed of the aerosol generator, and weighing the mass loss M' of the aerosol generating system in real time by using a balance 73. And calculating to obtain the concentration C in the cavity as M'/Q.
Step S2), before the measurement, the initial signal I of the laser measuring system is determined0. Collecting signals of a laser measurement system in real time, selecting an average value I 'of a stable section, and obtaining the light transmittance T ═ I'/I0. Plotting the square T of the transmittance2And fitting the curve to obtain a corresponding fitting formula f (x).
Step S3), adding fuel oil (such as n-heptane, gasoline, diesel oil, aviation kerosene and the like) on the gravity oil supply device, and adjusting the position of the gravity oil supply device to ensure that the distance between the liquid level of the fuel in the combustion cup and the top of the cup is within 5-10 mm. And opening the waste gas collecting device and the air compression pump, adjusting the flow of air to be 10L/min, igniting the fuel, and pre-burning for 60 s. The fuel tube can also be connected to carry out ignition test on the combustible gas.
Step S4), starting the aerosol generator, gradually adjusting the powder feeding rate from slow to fast, recording a concentration value q measured by a laser measurement system when the root of the flame is suspended from a stable state and continuously pulsates, and repeatedly carrying out the experiment for many times to finally obtain the critical fire extinguishing concentration of the specified superfine dry powder fire extinguishing agent:
wherein q' represents the average of the measured concentration values, qiRepresents the concentration value measured at the i-th time, and n represents the total number of measurements.
Before the test is started, the laser measuring system 4 needs to be calibrated, wherein the laser measuring system 4 comprises a laser emitting end and a laser receiving end, and the angle is 180 degrees. In some embodiments, the laser measurement and laser emission ends are disposed at the same end or at other angles. While the transmission signal of light is measured, in some embodiments, the scattering and diffraction signals of the powder may also be measured. The specific calibration process is as follows:
the gas supply section 71 includes a controller operable to regulate the flow of gas Q, which may be regulated. In some embodiments, gas source portion 71 may be high purity nitrogen, dry air, or a device or system that provides the relevant gas. Depending on the measurement environment and the usage scenario. The aerosol generator 72 thoroughly mixes the powder sample with the gas stream to form a polydisperse aerosol. In some embodiments, the aerosol generator is selected from the RGB-1000 model produced by PALAS, Germany. The system is capable of a constant, measured, diffusion mass flow rate at the highest level, ranging from about 10mg/h to about 430 g/h. The aerosol generator is conveyed to the rotary brush through the piston, the rotary brush can accurately convey a certain amount of samples to the diffusion head, the air flow is accelerated at the diffusion head through the acceleration of the nozzle, the high-speed air flow provides necessary turbulence and shearing force for the sufficient dispersion of the powder, the agglomerated particles are finally dispersed and output, and the output aerosol is in polydisperse distribution.
The laser test system is placed in a calibration system, the air quantity of an air source is adjusted to be Q, the feeding speed of the aerosol generator is set, and the mass loss M' of the aerosol generation system is weighed in real time by using a balance 73. And calculating to obtain the concentration C in the cavity as M'/Q.
Determining an initial signal I of the laser measuring system before the measurement is carried out0. Collecting signals of a laser measurement system in real time, selecting an average value I 'of a stable section, and obtaining the light transmittance T ═ I'/I0. Plotting the square T of the transmittance2And fitting the curve to obtain a corresponding fitting formula f (x), wherein the error is maximally-17%.
Adding fuel oil (such as n-heptane, gasoline, diesel oil, aviation kerosene and the like) to the gravity oil supply device, and adjusting the position of the gravity oil supply device to ensure that the distance between the fuel liquid level of the combustion cup and the top of the cup is within 5-10 mm. Opening the waste gas collecting device and an air compression pump, adjusting the flow of air to be 10L/min, igniting fuel, and pre-burning for 60 s; in some embodiments, a gas may also be used as a fuel, and the critical fire suppression concentration of the fire suppressant for a certain gas fuel is measured.
Starting the aerosol generator, gradually adjusting the powder feeding rate from slow to fast, recording a concentration value q measured by a laser measurement system when the flame is observed to be suspended from the root in a stable state and continuously pulsated, and repeatedly carrying out the experiment for many times, wherein the critical fire extinguishing concentration of the specified superfine dry powder fire extinguishing agent is finally obtained as follows:
the above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents or improvements made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (3)
1. The utility model provides a superfine dry powder extinguishing agent efficiency testing arrangement that puts out a fire which characterized in that, the device includes: an air inlet system (1), an aerosol generating system (2), a device supporting system (3), a laser measuring system (4), a cup type burner (5), an exhaust gas collecting and processing system (6) and a calibration system (7), wherein,
the air intake system (1) sends dry and clean compressed air to the aerosol generating system (2) to form stable aerosol which is sent to the cup-type combustor (5), and the concentration of the generated aerosol can be accurately controlled by adjusting the air flow of the air intake system (1) and the powder feeding rate of the aerosol generating system (2); by adjusting the concentration of the aerosol, the flame of the cup-type burner is separated from the bottom of the flame gradually from the stability to generate flame pulsation, namely the critical extinguishing phenomenon of the flame, and the concentration is detected by using a laser system (4), namely the corresponding critical extinguishing concentration of the extinguishing agent;
the air intake system (1) comprises an air compression pump (11), a water and oil removing filter (12) and an air flow controller (13);
the aerosol generating system (2) can uniformly mix air and superfine powder to form stable polydisperse distributed solid aerosol;
the device supporting system (3) is used for supporting and fixing the main body testing device;
the laser measurement system (4) can measure the change of the powder concentration in real time, the laser measurement system (4) comprises a laser emitting end and a laser receiving end, and before the laser measurement system is used, the laser measurement system is calibrated in the calibration system (7); the calibration system (7) comprises a gas source part (71), an aerosol generator (72), a balance (73), a calibration section (74), a data acquisition system (75), a test pipeline (76), a powder capture system (77) and a gas pipe (78); the gas source part (71) comprises a controller which can be used for adjusting the gas flow rate Q and can be adjusted by the gas flow rate; an aerosol generator (72) for intimately mixing the powder sample with the gas stream to form a polydisperse aerosol; the aerosol generator is conveyed to the rotary brush through the piston, the rotary brush accurately conveys a certain amount of samples to the diffusion head, at the diffusion head, the airflow is accelerated through the acceleration of the nozzle, the high-speed airflow provides necessary turbulence and shearing force for the full dispersion of the powder, the agglomerated particles are finally dispersed and output, and the output aerosol is in polydisperse distribution; the generated aerosol enters a test pipeline (76), and is uniformly diffused for a certain distance, and finally, the particle speeds of different particle sizes reach stability and move downwards at a constant speed; the balance (73) measures the mass loss of the powder in the aerosol generator in real time and acquires and processes data through the data acquisition system (75);
the cup type combustor (5) comprises a gravity oil supply device (51), a connecting port (52), a combustion cup (53), an aerosol connecting port (54), a metal diffusion section (55), an observation section (56), a metal connecting cylinder (57), a rectifying screen (58) and an experimental measurement section (59); wherein, the gravity oil supply device (51) is connected with the combustion cup (53) through a pipeline, the constant of the liquid level of the combustion cup (53) in the combustion process is ensured by utilizing the communicating vessel principle, and preferably, the ratio of the surface area S1 of the gravity oil supply device (51) to the surface area S2 of the combustion cup, namely S1: s2> 100; the connecting port (52) is not only connected with the gravity oil supply device (51) but also connected with a combustible gas pipeline; aerosol generated by the aerosol generating system (2) passes through the aerosol connecting port (54), passes through the metal diffusion section (55), the observation section (56), the metal connecting cylinder (57) and the rectifying screen (58) and reaches the experimental measurement section (59);
the exhaust gas treatment system (6) is used for collecting the generated aerosol.
2. The fire extinguishing efficiency testing device of the ultra-fine dry powder fire extinguishing agent according to claim 1, wherein the ratio of the surface area S1 of the gravity oil supply device (51) to the surface area S2 of the combustion cup is S1: s2> 100.
3. A method for testing the fire extinguishing efficiency of an ultrafine dry powder fire extinguishing agent is characterized by comprising the following steps:
step S1), placing the laser testing system in a calibration system, adjusting the air volume of an air source to be Q, setting the feeding speed of an aerosol generator, weighing the mass loss M 'of the aerosol generating system in real time by using a balance (73), and calculating to obtain the concentration C in the cavity to be M'/Q;
step S2), before the measurement, determining an initial signal I of the laser measuring system0Acquiring the signal of the laser measuring system in real time, and selecting the average value I 'of the stable section to obtain the light transmittance T ═ I'/I0Drawing the square T of the transmittance2And a corresponding curve of the concentration C, and fitting the curve to obtain a corresponding fitting formula f (x);
step S3) adding fuel oil on the gravity oil supply device, adjusting the position of the gravity oil supply device to ensure that the distance between the fuel liquid level of the combustion cup and the top of the cup is within 5-10 mm, opening the waste gas collecting device and the air compression pump, adjusting the flow of air to be 10L/min, igniting the fuel, pre-burning for 60S, and also connecting a fuel pipe to carry out ignition test on the combustible gas;
step S4), starting the aerosol generator, gradually adjusting the powder feeding rate from slow to fast, recording a concentration value q measured by a laser measurement system when the root of the flame is suspended from a stable state and continuously pulsates, and repeatedly carrying out the experiment for many times to finally obtain the critical fire extinguishing concentration of the specified superfine dry powder fire extinguishing agent:
q' represents the mean value of the concentration values measured, qiRepresents the concentration value measured at the i-th time, and n represents the total number of measurements.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011288170.6A CN112345688A (en) | 2020-11-17 | 2020-11-17 | Device and method for testing fire extinguishing efficiency of superfine dry powder extinguishing agent |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011288170.6A CN112345688A (en) | 2020-11-17 | 2020-11-17 | Device and method for testing fire extinguishing efficiency of superfine dry powder extinguishing agent |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112345688A true CN112345688A (en) | 2021-02-09 |
Family
ID=74364019
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011288170.6A Pending CN112345688A (en) | 2020-11-17 | 2020-11-17 | Device and method for testing fire extinguishing efficiency of superfine dry powder extinguishing agent |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112345688A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113702356A (en) * | 2021-10-28 | 2021-11-26 | 中国民航大学 | Dry powder extinguishing agent performance testing system and method based on gas Raman spectrum |
| CN115791554A (en) * | 2023-01-06 | 2023-03-14 | 南京理工大学 | Powder dynamic concentration measuring device and method |
-
2020
- 2020-11-17 CN CN202011288170.6A patent/CN112345688A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113702356A (en) * | 2021-10-28 | 2021-11-26 | 中国民航大学 | Dry powder extinguishing agent performance testing system and method based on gas Raman spectrum |
| CN115791554A (en) * | 2023-01-06 | 2023-03-14 | 南京理工大学 | Powder dynamic concentration measuring device and method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN214473064U (en) | Superfine dry powder extinguishing agent fire extinguishing efficiency testing device | |
| Wu et al. | Quantifying black carbon light absorption enhancement with a novel statistical approach | |
| CN112345688A (en) | Device and method for testing fire extinguishing efficiency of superfine dry powder extinguishing agent | |
| CN107192648B (en) | Method and system for measuring uncertainty of D50 of PM2.5 cutter | |
| Cheng et al. | Incense smoke: characterization and dynamics in indoor environments | |
| CN104777006B (en) | Device for testing dust generation and device and method for evaluating purification effect | |
| CN112304835A (en) | Calibration device and calibration method for high-concentration powder tester | |
| Moallemi et al. | Characterization of black carbon particles generated by a propane-fueled miniature inverted soot generator | |
| CN102445409A (en) | Device and method for measuring dust concentration based on digital image technology | |
| Smallwood et al. | Concurrent quantitative laser-induced incandescence and SMPS measurements of EGR effects on particulate emissions from a TDI diesel engine | |
| CN111965083A (en) | Particulate matter calibration system | |
| Perera et al. | Design and development of a dust dispersion chamber to quantify the dispersibility of rock dust | |
| Kholghy et al. | Morphology, composition and optical properties of jet engine-like soot made by a spray flame | |
| CN208187905U (en) | A kind of simulation inside fire flue gas measurement Visualization platform | |
| EP2851673A1 (en) | A soot generating device | |
| CN210863654U (en) | A burning and fire extinguishing process integrated analysis device for cup type combustor | |
| CN205683458U (en) | A kind of superfine spray critical extinguishing concentration experimental provision | |
| CN106855490A (en) | Method for generation, device of the air clearing product performance test with dirt source and the dirt source | |
| Johnson et al. | Development of techniques to characterize particulates emitted from gas turbine exhausts | |
| CN212790918U (en) | Aerosol generating device | |
| CN112525579A (en) | Portable standard cooking fume generator | |
| CN201251572Y (en) | Gas inflammability-testing tester | |
| Heist et al. | Development of a versatile aerosol generation system for use in a large wind tunnel | |
| Misra et al. | Investigation of aerosol mass and number deposition velocity in a closed chamber | |
| CN221260894U (en) | Gas combustion speed tester |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |