CN106906350B - A kind of H profile steel base heating process temperature distribution calculation method - Google Patents
A kind of H profile steel base heating process temperature distribution calculation method Download PDFInfo
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- CN106906350B CN106906350B CN201710073877.7A CN201710073877A CN106906350B CN 106906350 B CN106906350 B CN 106906350B CN 201710073877 A CN201710073877 A CN 201710073877A CN 106906350 B CN106906350 B CN 106906350B
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/70—Furnaces for ingots, i.e. soaking pits
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D11/00—Process control or regulation for heat treatments
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Abstract
The invention discloses a kind of H profile steel base heating process temperature distribution calculation methods, belong to metallurgical automation process control field.The computational methods include:According to initial furnace temperature setting value, the furnace temperature of steel billet position in stove is determined;It chooses comprising the zoning including water beam, carries out mesh generation;Calculate the heat flow density of billet surface;Reach heating time and meet heating requirements and export steel billet temperature later, and draws slab heating-up curve.The present invention has fully considered between water beam and steel billet and by the heat exchange that water beam bridging effect generates, and keeps the slab heating-up curve of drafting and measured value closer, and when online production is energy-saving.
Description
Technical field
The present invention relates to metallurgical automation process control fields, specifically, more particularly to a kind of H profile steel base heating process temperature
Spend distribution calculation method.
Background technology
Industrial furnace is the rich and influential family of AND ENERGY RESOURCES CONSUMPTION IN CHINA, and the energy consumed accounts for about 25% or so of national total energy consumption.
Only just there are more than 5000 seat of various heater for rolling steel, energy consumption to account for about the 60~70% of metallurgy industry total energy consumption in metallurgical system.Closely
Nian Lai, as a result of integrated energy saving technology, the typical case such as heater for rolling steel, soaking pit, heat-treatment furnace and forge furnace achieves
Certain energy-saving benefit, but gap is still very big compared with foreign iron and steel enterprise.It can be seen that the potentiality of China's Energy-saving in Industrial Furnaces
Very big, the power-saving technology for promoting industrial furnace has a very important significance.
Radiation heat transfer of the H profile steel base in walking beam furnace burner hearth is the major way of heat transfer, the matter of H-type heating steel billet
Amount directly affects the quality and yield of steel, heats H profile steel base with rational heating cycle, reaches after so that H profile steel base is come out of the stove
The required Temperature Distribution of rolling is conducive to the quality for improving steel.It usually can not directly measure and show that H profile steel base adds in stove
The Temperature Distribution of thermal process, and the method for using mathematical simulation obtains.The mathematical model of Heat Transfer in Furnace research is generally used
One-dimensional long stove model, i.e., be divided into several stove sections by furnace superintendent, and the temperature of this section is replaced with average furnace gas temperature in each stove section
Distribution, will generally consider the radiation heat transfer between each stove section, without considering in stove between water beam sliding block and H profile steel base and by water
The heat exchange that beam bridging effect generates so that the H profile steel base that model is calculated heating curve in stove has very big with measured value
Deviation.
Invention content
In view of the foregoing, it is an object to a kind of H profile steel base heating process temperature distribution calculation method is provided, it will
Between water beam sliding block and H profile steel base and heat exchange caused by water beam bridging effect is taken into account, and is calculated with solving model
To H profile steel base have the problem of very large deviation in heating process in the stove heating curve and measured value.
To achieve the goals above, the present invention uses technical solution below:
H profile steel base heating process temperature distribution calculation method of the present invention, wherein activity is distributed in heating furnace
Beam is provided with water beam in walking beam, includes the following steps:
1) according to initial furnace temperature setting value, the furnace temperature of steel billet position in stove is determined;
2) zoning is chosen, and water beam is included in by zoning, and mesh generation is carried out to zoning;
3) heat flow density of billet surface is calculated;
4) judge whether to reach setting heating time, if not up to, continuing to calculate, if reaching, carrying out step 5);
5) judge whether to meet heating requirements, if not satisfied, step 1) is then back to, if satisfied, then carrying out step 6);
6) steel billet temperature is exported, and draws slab heating-up curve.
7) terminate.
Preferably, furnace temperature of heating furnace is the function along furnace superintendent directional spreding, according to the position of thermocouple in heating furnace, is used
The method of linear interpolation determines the furnace temperature of steel billet position in stove.
Preferably, in step 2), when carrying out mesh generation to zoning, at the positions Shui Liang and H profile steel base abdomen
Plate and wing plate junction use closeer mesh generation, other positions to be divided using proportional density.
Preferably, in step 2), the steel billet two-dimension unsteady heat conduction differential equation is established in mesh point, respectively in the x-direction
With y discrete--direction steel billets section, the Temperature Distribution at this moment is determined according to the Temperature Distribution of steel billet previous moment and furnace temperature, if
To calculate for the first time, then the Temperature Distribution at this moment is initial temperature.
Further, it is preferable to, steel billet upper surface is set as heat flow density boundary condition, and steel billet lower surface is contacted with water beam
Place is set as third boundary condition, and steel billet lower surface other positions are set as heat flow density boundary condition.
Further, in step 3), according between adjacent steel billet RADIATION ANGLE COEFFICIENT, furnace gas is to the heat convection of steel billet
Coefficient, furnace gas blackness, furnace gas absorptivity and furnace gas calculate the RADIATION ANGLE COEFFICIENT of steel billet on the heat flow density of billet surface, steel billet
The heat flow density of upper and lower surface is according to the following formula:
In formula, qTFor the heat flow density of steel billet upper surface, W/m2;qBFor the heat flow density of steel billet lower surface, W/m2;K is to repair
Positive coefficient;σgFor combined radiation coefficient, W/ (m2·K4);TfFor furnace temperature, DEG C;TsFor billet surface temperature, DEG C;TwFor in water beam
Water temperature, DEG C;H is convection transfer rate, W/ (m2·K);
The heat flow density of steel billet both sides is:
qL=α qT+(1-α)qB
In formula, qLFor the heat flow density of steel billet side, W/m2;α is coefficient, and 0 < α < 1.
Preferably, in step 6), the steel billet temperature of output is the disconnected of billet surface temperature, steel billet central temperature and steel billet
The face temperature difference.
Water beam is included in it by the computational domain of H profile steel base heating process temperature distribution calculation method of the present invention, selection
In, by between water beam sliding block and steel billet heat exchange and taken into account by heat exchange caused by water beam bridging effect so that
The slab heating-up curve and measured value being calculated are closer, and when online production can play energy-saving effect.
Description of the drawings
Fig. 1 is the flow chart of computational methods of the present invention;
Fig. 2 is the physical model schematic diagram of the present invention;
Fig. 3 is mesh generation schematic diagram of the present invention to H profile steel base.
Specific implementation mode
In conjunction with attached drawing, the present invention is described further, in order to which it is more clear and should be readily appreciated that.
Fig. 1 is the flow chart of computational methods of the present invention.As shown in Figure 1, walking beam is distributed in heating furnace, activity
It is provided with water beam in beam, when carrying out the distribution calculating of H profile steel base heating process temperature, includes the following steps:
1) the initial furnace temperature setting value of each section of heating furnace is inputted, drafts heating furnace in-furnace temperature by entering stove end to the temperature at end of coming out of the stove
Distribution curve is spent, position of the steel billet in stove is judged, determines the furnace temperature of position;
Wherein, about the calculating of furnace temperature of heating furnace, setting furnace temperature of heating furnace is the function along furnace superintendent directional spreding, according to adding
The position of thermocouple in hot stove, the furnace temperature of steel billet position in stove is determined using the method for linear interpolation, as entire meter
The basis of calculation.Each pre-buried 1~2 thermocouple of stove Duan Junhui in heating furnace.
2) zoning is chosen, and water beam is included in by zoning, and mesh generation is carried out to zoning;
3) by calculate the RADIATION ANGLE COEFFICIENT between adjacent steel billet, furnace gas to the convection transfer rate of steel billet, furnace gas blackness,
Furnace gas absorptivity and furnace gas calculate the heat flow density of billet surface to the RADIATION ANGLE COEFFICIENT of steel billet;
4) judge whether to reach setting heating time, if not up to, continuing to calculate, if reaching, carrying out step 5),
In, heating time of the steel billet in stove sets according to different steel grades and billet bloom size;
5) judge whether to meet heating requirements, if not satisfied, step 1) is then back to, if satisfied, then carrying out step 6);
6) steel billet temperature is exported, and draws slab heating-up curve, wherein the steel billet temperature of output is at steel billet critical positions
Temperature, include the section temperature difference of billet surface temperature, steel billet central temperature and steel billet.
7) terminate.
In step 2), when carrying out mesh generation to zoning, at the positions Shui Liang and H steel billets web and wing plate are handed over
Meeting place uses closeer mesh generation, other positions to be divided using proportional density.
Computation model is simplified, is made the following assumptions:
A) furnace does not change over time, it is believed that and medium temperature is uniform in being segmented in burner hearth, and
Ignore the radiation heat transfer between each stove section in furnace superintendent direction;
B) ignore the heat conduction along steel billet length direction, since steel billet gap is placed, can be close by the internal heat transfer of steel billet
Seemingly think the two-dimension unsteady heat conduction that endless base is upper and lower and both sides four sides is heated, and thinks that the heating condition of two sides is identical;
C) ignore influence of the iron scale to heat transfer of billet surface;
D) furnace wall inner surface and billet surface blackness are considered as constant.
Steel billet heats in walking beam furnace, billet surface by furnace gas, the radiant heat transfer of furnace wall and furnace gas convection current
Heat transfer, inside steel billet transmit heat in thermo-conducting manner.The two-dimension unsteady heat conduction of inside steel billet heat conduction is established in mesh point
The differential equation considers that inside steel billet temperature changes along width and short transverse, respectively in the x-direction with y discrete--direction steel billets
Section, as shown in Fig. 2, the Temperature Distribution at this moment is determined according to the Temperature Distribution of steel billet previous moment and furnace temperature, if first
Secondary calculating, then the Temperature Distribution at this moment is initial temperature.
The inside steel billet two-dimension unsteady heat conduction differential equation, is specifically expressed as follows:
In formula, ρ indicates the density of steel billet, unit K g/m3;Cp indicates the specific heat of steel billet, unit J/ (kg DEG C);T is indicated
Steel billet temperature, unit DEG C;τ indicates time, unit s;λ indicates steel billet thermal coefficient, unit W/ (m DEG C).
Boundary condition is assumed and setting is as follows:
A) assume that upper and lower burner hearth fictitious emissivity method is identical in same stove section;
B) steel billet upper surface uses comprehensive heat flow density boundary condition,
C) third boundary condition is used at steel billet lower surface and water beam shoe contact position,
Steel billet lower surface other positions use comprehensive heat flow density boundary condition,
In formula,For heat flow density, unit W/m2;σ is Boltzmann constant, 5.67 × 10-8W/(m2·K4);φCFIt is total
Include thermal absorptivity;H is the coefficient of heat transfer, unit W/ (m2·K);TfFor furnace temperature, unit K;TsFor billet surface temperature, unit K;Tw
For the water temperature in water beam, unit K;
To the above-mentioned inside steel billet two-dimension unsteady heat conduction differential equation, using Iterative alternate differential reduced equation, make its at
To be solved to triangular matrix and with chasing method.
By black box experiment measure upper and lower burner hearth fictitious emissivity method and steel billet and water beam contact when heat exchange
Coefficient.
As shown in Figures 2 and 3, qTAnd qBSteel billet heat flow density upper and lower surfaces of, q are indicated respectivelyLIndicate steel billet side
Heat flow density.H profile steel base includes web 1 and wing plate 2, when carrying out mesh generation, in the junction of web 1 and wing plate 2 to net
Lattice are encrypted.
Calculate the RADIATION ANGLE COEFFICIENT between adjacent steel billet, furnace gas inhales the convection transfer rate, furnace gas blackness, furnace gas of steel billet
Yield and furnace gas calculate according to above-mentioned result of calculation the heat flow density of billet surface to the RADIATION ANGLE COEFFICIENT of steel billet, press
Following formula calculate the heat flow density of steel billet upper and lower surface:
In formula, qTFor the heat flow density of steel billet upper surface, unit W/m2;qBFor the heat flow density of steel billet lower surface, unit W/
m2;K is correction factor;σgFor combined radiation coefficient, unit W/ (m2·K4);TfFor furnace temperature, unit DEG C;TsFor billet surface temperature
Degree, unit DEG C;TwFor the water temperature in water beam, unit DEG C;H is convection transfer rate, unit W/ (m2·K);εgFor furnace gas blackness system
Number;ε is billet surface coefficient of blackness, 0.8-0.85;It is furnace lining to billet surface ascent;LmFor steel billet length, unit m;
NmFor steel billet number of rows;H is furnace height, unit m;B is furnace width, unit m;
Wherein, the blackness ε of furnace gasgIt is calculated as follows:
In formula,For CO2Blackness;For H2The blackness of O;For CO2Partial pressure, unit atm;For H2O
Partial pressure, unit atm;S is mean beam length, unit m;
The heat flow density of steel billet both sides is:
qL=α qT+(1-α)qB
In formula, qLFor the heat flow density of steel billet side, unit W/m2;α is coefficient, and 0 < α < 1.
The foregoing is merely the preferred embodiment of the present invention, are not intended to restrict the invention, for those skilled in the art
For member, the invention may be variously modified and varied.Any modification made by all within the spirits and principles of the present invention,
Equivalent replacement, improvement etc., should all be included in the protection scope of the present invention.
Claims (7)
1. a kind of H profile steel base heating process temperature distribution calculation method, it is distributed with walking beam in heating furnace, in the walking beam
It is provided with water beam, which is characterized in that include the following steps:
1) according to initial furnace temperature setting value, the furnace temperature of steel billet position in stove is determined;
2) zoning is chosen, and the water beam is included in by the zoning, and net is carried out to the zoning
Lattice divide;
3) heat flow density of billet surface is calculated;
4) judge whether to reach setting heating time, if not up to, continuing to calculate, if reaching, carrying out step 5);
5) judge whether to meet heating requirements, if not satisfied, the step 1) is then back to, if satisfied, then carrying out step 6);
6) steel billet temperature is exported, and draws slab heating-up curve;
7) terminate.
2. computational methods according to claim 1, which is characterized in that in the step 1), furnace temperature of heating furnace is along stove
The function of length direction distribution is determined in stove using the method for linear interpolation where steel billet according to the position of thermocouple in heating furnace
Furnace temperature at position.
3. computational methods according to claim 1, which is characterized in that in the step 2), to the zoning into
When row mesh generation, at the positions Shui Liang and H profile steel base web and wing plate junction use closeer mesh generation, other positions
It sets and is divided using proportional density.
4. computational methods according to claim 1, which is characterized in that in the step 2), steel billet is established in mesh point
The two-dimension unsteady heat conduction differential equation, respectively in the x-direction with y discrete--direction steel billets section, according to the temperature of steel billet previous moment
Degree distribution and furnace temperature determine the Temperature Distribution at this moment, are calculated if first time, then the Temperature Distribution at this moment is initial temperature.
5. computational methods according to claim 4, which is characterized in that steel billet upper surface is set as heat flow density perimeter strip
Part, steel billet lower surface are set as third boundary condition with the contact positions Shui Liang, and it is close that steel billet lower surface other positions are set as hot-fluid
Spend boundary condition.
6. computational methods according to claim 1, which is characterized in that in the step 3), according between adjacent steel billet
The radiation to the convection transfer rate, furnace gas blackness, furnace gas absorptivity and furnace gas of steel billet to steel billet of RADIATION ANGLE COEFFICIENT, furnace gas
Ascent calculates the heat flow density of billet surface, and the heat flow density of steel billet upper and lower surface is according to the following formula:
In formula, qTFor the heat flow density of steel billet upper surface, W/m2;qBFor the heat flow density of steel billet lower surface, W/m2;K is to correct to be
Number;σgFor combined radiation coefficient, W/ (m2·K4);TfFor furnace temperature, DEG C;TsFor billet surface temperature, DEG C;TwFor the water in water beam
Temperature, DEG C;H is convection transfer rate, W/ (m2·K);
The heat flow density of steel billet both sides is:
qL=α qT+(1-α)qB
In formula, qLFor the heat flow density of steel billet side, W/m2;α is coefficient, and 0 < α < 1.
7. computational methods according to claim 1, which is characterized in that in the step 6), the steel billet temperature of output is
The section temperature difference of billet surface temperature, steel billet central temperature and steel billet.
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CN110307910B (en) * | 2019-05-24 | 2020-12-29 | 武汉钢铁有限公司 | Method and device for acquiring temperature of billet of walking beam heating furnace |
CN110231840B (en) * | 2019-06-05 | 2020-12-01 | 重庆赛迪热工环保工程技术有限公司 | Control method for black print temperature difference of water beam of steel billet in walking beam type heating furnace |
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CN114752753A (en) * | 2022-04-22 | 2022-07-15 | 浙江优燃节能科技有限公司 | Furnace temperature setting method suitable for H-shaped steel rolling heating furnace |
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