CN109100393A - The evaluation method of asphalt heat and mass behavioral implications when fire retardant is to fire - Google Patents
The evaluation method of asphalt heat and mass behavioral implications when fire retardant is to fire Download PDFInfo
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- CN109100393A CN109100393A CN201811006918.1A CN201811006918A CN109100393A CN 109100393 A CN109100393 A CN 109100393A CN 201811006918 A CN201811006918 A CN 201811006918A CN 109100393 A CN109100393 A CN 109100393A
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- 239000003063 flame retardant Substances 0.000 title claims abstract description 46
- 239000010426 asphalt Substances 0.000 title claims abstract description 34
- 238000011156 evaluation Methods 0.000 title claims abstract description 11
- 230000003542 behavioural effect Effects 0.000 title claims description 13
- 238000012360 testing method Methods 0.000 claims abstract description 27
- 238000012546 transfer Methods 0.000 claims abstract description 24
- 238000004088 simulation Methods 0.000 claims abstract description 12
- 238000002485 combustion reaction Methods 0.000 claims abstract description 11
- 239000000203 mixture Substances 0.000 claims abstract description 9
- 238000000034 method Methods 0.000 claims description 26
- 238000004786 cone calorimetry Methods 0.000 claims description 8
- 239000000463 material Substances 0.000 claims description 8
- 230000005855 radiation Effects 0.000 claims description 8
- 238000004458 analytical method Methods 0.000 claims description 7
- 235000019504 cigarettes Nutrition 0.000 claims description 4
- 238000002360 preparation method Methods 0.000 claims description 4
- 230000008859 change Effects 0.000 claims description 3
- 238000010304 firing Methods 0.000 claims description 3
- 239000005030 aluminium foil Substances 0.000 claims description 2
- 239000002245 particle Substances 0.000 claims description 2
- 230000007246 mechanism Effects 0.000 abstract description 6
- 230000008878 coupling Effects 0.000 abstract description 4
- 230000000694 effects Effects 0.000 abstract description 4
- 230000008676 import Effects 0.000 abstract description 4
- RNFJDJUURJAICM-UHFFFAOYSA-N 2,2,4,4,6,6-hexaphenoxy-1,3,5-triaza-2$l^{5},4$l^{5},6$l^{5}-triphosphacyclohexa-1,3,5-triene Chemical compound N=1P(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP=1(OC=1C=CC=CC=1)OC1=CC=CC=C1 RNFJDJUURJAICM-UHFFFAOYSA-N 0.000 abstract description 3
- 238000010168 coupling process Methods 0.000 abstract description 3
- 238000005859 coupling reaction Methods 0.000 abstract description 3
- 238000005516 engineering process Methods 0.000 abstract description 3
- 238000011161 development Methods 0.000 abstract description 2
- 239000000446 fuel Substances 0.000 abstract 1
- 230000005764 inhibitory process Effects 0.000 abstract 1
- 230000008569 process Effects 0.000 description 8
- 230000008901 benefit Effects 0.000 description 3
- 238000012512 characterization method Methods 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 230000002401 inhibitory effect Effects 0.000 description 2
- 238000012805 post-processing Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 239000002341 toxic gas Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000002041 carbon nanotube Substances 0.000 description 1
- 229910021393 carbon nanotube Inorganic materials 0.000 description 1
- 238000001311 chemical methods and process Methods 0.000 description 1
- 238000005094 computer simulation Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 239000003546 flue gas Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000013178 mathematical model Methods 0.000 description 1
- 239000002114 nanocomposite Substances 0.000 description 1
- 239000002086 nanomaterial Substances 0.000 description 1
- 239000002070 nanowire Substances 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N25/00—Investigating or analyzing materials by the use of thermal means
- G01N25/18—Investigating or analyzing materials by the use of thermal means by investigating thermal conductivity
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N25/00—Investigating or analyzing materials by the use of thermal means
- G01N25/20—Investigating or analyzing materials by the use of thermal means by investigating the development of heat, i.e. calorimetry, e.g. by measuring specific heat, by measuring thermal conductivity
- G01N25/22—Investigating or analyzing materials by the use of thermal means by investigating the development of heat, i.e. calorimetry, e.g. by measuring specific heat, by measuring thermal conductivity on combustion or catalytic oxidation, e.g. of components of gas mixtures
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- Chemical & Material Sciences (AREA)
- General Health & Medical Sciences (AREA)
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- Analytical Chemistry (AREA)
- Biochemistry (AREA)
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- Immunology (AREA)
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Abstract
本发明是一种阻燃剂对火灾时沥青混合料传热传质行为影响的评价方法，属于沥青路面技术领域，解决目前只能通过宏观试验表征阻燃剂对沥青混合料燃烧的抑制作用、没有评价阻燃剂对沥青混合料燃烧过程中传热、传质行为影响、不能揭示阻燃剂对混合料阻燃机理的问题。本发明首先制备沥青混合料车辙板试件，切割成锥形量热仪试件，测得用于多场耦合数值模拟的试验参数；其次，在Auto CAD中建立隧道沥青路面燃烧数值模型，导入COMSOL多场耦合软件，设置控制性方程组，求解各参数；最后，模拟分析不同火灾工况下阻燃剂对沥青路面温度场分布和传热传质行为影响，并与试验结果比较，评价阻燃剂对火灾时沥青混合料传热传质行为的影响，对研发高效阻燃剂具有重要意义。The invention relates to an evaluation method for the influence of flame retardants on the heat and mass transfer behavior of asphalt mixtures during fire, which belongs to the field of asphalt pavement technology, and solves the problem that currently only macroscopic tests can be used to characterize the inhibition of flame retardants on the combustion of asphalt mixtures. The effects of flame retardants on the heat transfer and mass transfer behavior during the combustion process of asphalt mixtures have not been evaluated, and the problem of the flame retardant mechanism of flame retardants on mixtures cannot be revealed. The present invention firstly prepares asphalt mixture rutting slab specimens, cuts them into conical calorimeter specimens, and measures test parameters for multi-field coupling numerical simulation; secondly, establishes a tunnel asphalt pavement combustion numerical model in Auto CAD, imports The COMSOL multi-field coupling software sets the governing equations and solves each parameter; finally, simulates and analyzes the effects of flame retardants on the temperature field distribution and heat and mass transfer behavior of asphalt pavement under different fire conditions, and compares with the test results to evaluate the flame retardant. The effect of fuel on the heat and mass transfer behavior of asphalt mixture during fire is of great significance to the development of high-efficiency flame retardants.
Description
Technical field
The present invention be a kind of fire retardant to fire when asphalt heat and mass behavioral implications evaluation method, belong to drip
Green pavement technique field.
Background technique
It is rapidly developed with highway in China and stereo urban traffic, a large amount of Tunnel Engineering has been built, because bituminous pavement is smooth, nothing
Seam, driving is comfortable, with small vibration, low noise, wear-resisting, the construction time is short, maintenance is easy, reproducible utilization, is suitable for stage construction etc.
Advantage is used widely in tunnel road surface.But bituminous pavement can thermally decompose under high temperature environment, discharge big calorimetric
And poison gas, lead to mass casualties and property loss.Currently used flame resistant method is that one is added in bituminous pavement
Quantitative fire retardant inhibits the burning of fire process bituminous pavement, reduces poison gas and is precipitated.
When fire occurs for tunnel, tunnel fire hazard is a kind of out of control combustion phenomena, is occurred, development and extinguishing are
One complicated physical and chemical process changed over time, including the burning of a variety of combustibles, gas Complex Flows and each
The heat and mass behavior of kind form.There is researcher to think that the burning situation of cone calorimetry test method simulation is similar to really
Burning situation, and can truly reflect the combustibility of asphalt under fire conditions, measure test result and large-scale simulation
Fire test has good correlation, measured test data, such as ignitor firing time, heat release rate, total release heat, mass loss
The parameters such as rate, cigarette generating rate, active combustion heat can be used to evaluate the combustibility of asphalt, research nanometer resistance
Agent is fired to the fire retardant mechanism of asphalt, also data can be used for numerical simulation, is designed for nanocomposite and fiery
Calamity modeling provides more data..
COMSOL software can be used for the various physical processes in model engineering field, have efficient calculated performance and more
Direct coupling analysis ability realizes any multiple physical field exact numerical emulation.It has lot of advantages, can such as solve more
Problem has completely open framework, and the parameter that can be solved according to any independent function control has the calculating of profession
Model library embeds CAD modeling tool abundant and has comprehensive third party CAD import feature, has powerful mesh generation
Ability has large-scale calculations ability, possesses post-processing function abundant.The soluble problem packet of the software thermal conduction module
It includes: conducting, any combination of radiation and convection current.Modeling interface type includes: that surface-to-surface radiates, non-isothermal flows, in active mass
Heat transfer and thin layer and shell in heat transfer etc..Hot transfer module largely extends base in the kernel software packet
The analytic function of this heat transfer.One most important improvement is the Modeling interface of surface-to-surface radiation, this is its significant advantage.This
Outside, for the heat transfer process by conduction, convection current and radiation, the model interface of foundation can more easily define complicated heat
Problem of transmission.Hot transfer module also achieves complete multiple physical field coupling analysis function, this makes heat transmitting and other field
It is coupled together analyze and be possibly realized.
The model library of hot transfer module is divided into three parts, including heat analysis, heat treatment and hot-working in electronics industry, doctor
Treatment technology and biomedicine.The new feature of hot transfer module include surface-to-surface radiation based on radiation principle, for free convection and
The non-isothermal flowing of thermal expansion has the flow boundary condition of any flow velocity to describe the running of fan, with low and high conductance
Thin layer and shell in heat transmitting, heat transfer process post-processing, can handle any heat transfer process high flexibility and
The outer heat transmitting boundary condition of broad applicability, plane, anisotropy pyroconductivity etc..
Foreign scholar establishes various nano-structured patterns using COMSOL, including carbon nanotube, nano wire, nanometer
Porous media etc., with the combination of operating automation nanotechnology and engineering technology, COMSOL is considered as being most suitable for doing
The software of nanostructure research.Method that Computer Numerical Simulation is combined with experimental study is to study tunnel fire hazard to have efficacious prescriptions
The loss of tunnel fire hazard can be preferably minimized by method using these methods.Fire computer simulation method is according to fire physics
The difference of the division of control volume and mathematical model in model survey region can be divided into field simulation, regional simulation, network analog three
Kind.
But current few researchers obtain combustion parameter based on the test of cone calorimetry, with COMSOL software
Numerical simulation is carried out to bituminous pavement combustion process during tunnel fire hazard, studies fire process fire retardant to tunnel sheet pavement
The influence of thermo parameters method, heat and mass rule in porous media.Pitch is mixed when the present invention provides a kind of fire retardant to fire
The evaluation method of material heat and mass behavioral implications is closed, so that the fire retardant mechanism of fire retardant is deeply disclosed, it is high for targetedly research and development
The fire retardant of effect provides scientific basis.
Summary of the invention
(1) technical problem
The evaluation side of asphalt heat and mass behavioral implications when it is an object of the present invention to provide a kind of fire retardants to fire
Method, solve at present can only by macroscopic view test characterization fire retardant burn to asphalt inhibiting effect, be theoretically unsound,
Do not evaluate fire retardant to heat transfer during this multi-hole medium combustion of asphalt, mass transfer behavioral implications, cannot be from essence
The problem of upper announcement fire retardant is to asphalt fire retardant mechanism has to efficient asphalt fire retardant is further researched and developed
Significance.
(2) technical solution
In order to solve that inhibiting effect, the shortage that characterization fire retardant burns to asphalt can only be tested by macroscopic view at present
Theoretical foundation, without evaluation fire retardant to heat transfer during this multi-hole medium combustion of asphalt, mass transfer behavioral implications, no
The problem of fire retardant is to asphalt fire retardant mechanism can inherently be disclosed, the drip when present invention provides a kind of fire retardant to fire
The evaluation method of green mixture heat and mass behavioral implications, specific technical solution are as follows: preparing AC-13 gradation first and do not sum it up and add
The asphalt track plate test specimen of fire retardant is added to be cooled to room temperature rear demoulding, cutting track plate prepares cone calorimetry test specimen,
The upper surface for retaining former track plate is upward, and bituminous pavement is by thermal condition when simulated fire；Then, test specimen is lighted, is measured for more
The test parameters of field Coupled Numerical Simulation；Secondly, establishing tunnel sheet pavement burning numerical model in Auto CAD, import
COMSOL multi- scenarios method is analyzed in software, definition material attribute and boundary condition, and setting heat transfer, heat are transmitted and the control of heat radiation
Property equation group processed carries out grid dividing to model, solves each parameter by solver；Finally, changing different materials attribute, hot spoke
Intensity and boundary condition are penetrated, fire retardant is to asphalt pavement structure distribution law of temperature field under sunykatuib analysis difference tunnel fire hazard operating condition
It with heat and mass behavioral implications, and is compared with cone calorimetry test result, pitch mixes when evaluating fire retardant to fire
Expect the influence of heat and mass behavior.
(3) beneficial effect
Lack reliable data and parameter for tunnel fire hazard process bituminous pavement heat and mass Behavior modeling, lacks to drip
The evaluation method of green mixture heat transfer, mass transfer behavior, it is difficult to inherently disclose fire retardant porous Jie this to asphalt
The influence of the burning behavior of matter.Method provided by the invention is based on porous medium theory, establishes asphalt surface hot under tunnel fire hazard
Decomposition model, using method for numerical simulation to tunnel sheet pavement thermo parameters method in the case of tunnel fire hazard and heat and mass behavior
It is analyzed, influence of the fire retardant to bituminous pavement thermal decomposition process heat and mass behavior is studied, by experimental study and Numerical-Mode
It is quasi- to combine, further illustrate that asphalt fire retardant mechanism drops to more efficiently flame-retardant pitch material is researched and developed in fire retardant
Low fire hazard improves tunnel sheet pavement fire safety and is of great significance.
Specific embodiment
The evaluation method of asphalt heat and mass behavioral implications when the present invention provides a kind of fire retardants to fire, tool
Body implementation steps are as follows:
(1) SBS modified pitch and AC-13 gradation types are used, preparation length is 30cm, width 30cm, with a thickness of 5cm
Asphalt track plate test specimen two, one is not added fire retardant, and the fire retardant of another addition 8% is torn open after being cooled to room temperature
Mould；
(2) cutting track plate preparation length is that 10cm, width 10cm are wrapped up with aluminium-foil paper and being bored with a thickness of the test specimen of 4cm
Shape calorimeter test specimen bottom and side carry out cone calorimetry test, and the upper surface for retaining former track plate is upward, when simulated fire
Bituminous pavement is by thermal condition；
(3) test specimen is lighted, the test parameters for multi- scenarios method numerical simulation, including ignitor firing time, heat release speed are measured
Rate, total release heat, mass loss rate, cigarette generating rate and active combustion heat；
(4) tunnel sheet pavement burning numerical model is established in Auto CAD, and it is soft to import the analysis of COMSOL multi- scenarios method
In part, definition material attribute and boundary condition, setting heat transfer, heat are transmitted and the controlling equation group of heat radiation；
(5) grid dividing is carried out to model, each parameter is solved by solver, post-treated realization calculated result is visual
Change, 2 d plane picture, 3 dimensional drawing, isogram, polar plot, deformation pattern, the streamline of each parameter are calculated needed for intuitively drawing
Figure and flue gas particles track figure；
(6) change different materials attribute, caloradiance and boundary condition, hindered under sunykatuib analysis difference tunnel fire hazard operating condition
Agent is fired to asphalt pavement structure distribution law of temperature field and heat and mass behavioral implications, and is carried out with cone calorimetry test result
Compare, the influence of asphalt heat and mass behavior when evaluating fire retardant to fire.
Claims (1)
1. the present invention be a kind of fire retardant to fire when asphalt heat and mass behavioral implications evaluation method, feature exists
In this method, specific step is as follows:
(1) SBS modified pitch and AC-13 gradation types are used, preparation length is 30cm, width 30cm, with a thickness of 5cm pitch
Mixture track plate test specimen two, one is not added fire retardant, and the fire retardant of another addition 8% is cooled to room temperature rear demoulding；
(2) cutting track plate preparation length is 10cm, width 10cm, with a thickness of the test specimen of 4cm, wraps up taper amount with aluminium-foil paper
Hot instrument test specimen bottom and side carry out cone calorimetry test, and the upper surface for retaining former track plate is upward, pitch when simulated fire
Road surface is by thermal condition；
(3) test specimen is lighted, measures the test parameters for multi- scenarios method numerical simulation, including is ignitor firing time, heat release rate, total
Discharge heat, mass loss rate, cigarette generating rate and active combustion heat；
(4) tunnel sheet pavement burning numerical model is established in Auto CAD, is imported in COMSOL multi- scenarios method analysis software,
Definition material attribute and boundary condition, setting heat transfer, heat are transmitted and the controlling equation group of heat radiation；
(5) grid dividing is carried out to model, each parameter is solved by solver, post-treated realization calculated result visualizes, directly
See 2 d plane picture, 3 dimensional drawing, isogram, polar plot, deformation pattern, motion pattern and the cigarette that each parameter is calculated needed for drawing
Gas particles track figure；
(6) change different materials attribute, caloradiance and boundary condition, fire retardant under sunykatuib analysis difference tunnel fire hazard operating condition
Compared to asphalt pavement structure distribution law of temperature field and heat and mass behavioral implications, and with cone calorimetry test result
Compared with the influence of asphalt heat and mass behavior when evaluating fire retardant to fire.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811006918.1A CN109100393A (en) | 2018-08-28 | 2018-08-28 | The evaluation method of asphalt heat and mass behavioral implications when fire retardant is to fire |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811006918.1A CN109100393A (en) | 2018-08-28 | 2018-08-28 | The evaluation method of asphalt heat and mass behavioral implications when fire retardant is to fire |
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| Publication Number | Publication Date |
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| CN109100393A true CN109100393A (en) | 2018-12-28 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811006918.1A Pending CN109100393A (en) | 2018-08-28 | 2018-08-28 | The evaluation method of asphalt heat and mass behavioral implications when fire retardant is to fire |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110728092A (en) * | 2019-10-22 | 2020-01-24 | 陕西铁路工程职业技术学院 | Method for establishing and using temperature coupling model of mixed asphalt pavement structure |
-
2018
- 2018-08-28 CN CN201811006918.1A patent/CN109100393A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110728092A (en) * | 2019-10-22 | 2020-01-24 | 陕西铁路工程职业技术学院 | Method for establishing and using temperature coupling model of mixed asphalt pavement structure |
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Application publication date: 20181228 |