CN110765623A - Two-dimensional rapid calculation method for erosion boundary of longitudinal section of blast furnace hearth - Google Patents
Two-dimensional rapid calculation method for erosion boundary of longitudinal section of blast furnace hearth Download PDFInfo
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- 230000003628 erosive effect Effects 0.000 title claims abstract description 70
- 238000004364 calculation method Methods 0.000 title claims abstract description 58
- 238000000034 method Methods 0.000 claims abstract description 22
- 238000013213 extrapolation Methods 0.000 claims description 2
- 230000009286 beneficial effect Effects 0.000 abstract description 3
- 238000001514 detection method Methods 0.000 abstract description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract 1
- 239000011449 brick Substances 0.000 abstract 1
- 229910052799 carbon Inorganic materials 0.000 abstract 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 18
- 229910052742 iron Inorganic materials 0.000 description 9
- 238000012937 correction Methods 0.000 description 4
- 238000012546 transfer Methods 0.000 description 4
- 238000013178 mathematical model Methods 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000015271 coagulation Effects 0.000 description 1
- 238000005345 coagulation Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000009851 ferrous metallurgy Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000009991 scouring Methods 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
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Abstract
The invention provides a two-dimensional rapid calculation method for a blast furnace hearth longitudinal section erosion boundary, which is used for reversely calculating the position of the hearth erosion boundary by acquiring a temperature value detected by a thermocouple group arranged in a hearth carbon brick. The method comprises the steps of firstly obtaining a temperature value of an outer boundary of a calculation area by adopting a method based on a fixed structured grid, determining the calculation area, then obtaining the calculation temperatures of all inner-ring thermocouples by taking a series of assumed erosion line positions, preliminarily calculating an initial inner-wall erosion line by utilizing a linear interpolation method, and then comparing and correcting the initial inner-wall erosion line with an actual inner-ring thermocouple temperature value for multiple times until an error range meets the requirement. The two-dimensional rapid calculation method for the vertical section of the blast furnace hearth erosion boundary under the fixed calculation domain grid provided by the invention is beneficial to relieving the technical problems that the erosion detection iteration method in the prior art is too long in time consumption, large in calculation amount, not beneficial to rapid estimation of the obtained result in engineering and common calculation hardware cannot meet the calculation requirement.
Description
Technical Field
The invention relates to the technical field of blast furnace hearth erosion detection, in particular to a two-dimensional rapid calculation method for an erosion boundary of a longitudinal section of a blast furnace hearth.
Background
The iron and steel industry is an important industry in China, and the iron and steel yield is always in the first place in the world for over a decade. The blast furnace is one of key equipment in the production of ferrous metallurgy and is a main equipment carrier in the iron-making process. The service life of the blast furnace determines the economic efficiency of blast furnace ironmaking due to the very high construction and maintenance costs. Among the many factors that affect the useful life of blast furnaces, lining erosion is one of the most important. The difficulty of erosion prediction is that molten iron can cover the erosion part of the hearth lining, so that the erosion state of the hearth lining cannot be directly observed. In order to prevent the blast furnace hearth from being burnt through, a mathematical model describing the thermal process of the blast furnace hearth needs to be established, and the erosion analysis calculation of the hearth lining is carried out. And judging the erosion appearance and thickness of the hearth lining in the middle and later service periods of the blast furnace, and reasonably arranging the furnace protection and overhaul periods to ensure the safety of the hearth structure. Meanwhile, the existing thermotechnical measurement condition parameters are required to be fully utilized as far as possible, the state is close to the real state to the maximum extent, and the working state of the hearth lining is correctly reflected.
Generally, mathematical models for erosion of blast furnace hearth linings are based on heat transfer science. Different mathematical models are established according to thermal parameters such as temperature, heat flow and the like, and are continuously developed. Studies on the problem of blast furnace hearth erosion are generally divided into forward solution models and inverse solution models. The forward solution model predicts the erosion position according to the erosion mechanism, but because the erosion mechanism of the hearth lining is very complex, and many aspects such as oxidation, thermal stress, mechanical scouring and the like are involved, the yield and medium are also very complex, so that the prediction of the position of the erosion line from the forward problem is very difficult. The inverse solution model directly utilizes the temperature, heat flow and other existing measurable thermal parameters of the blast furnace hearth in service to determine the corrosion state of the lining. Namely, under the condition of known parameters of the geometric boundary of the part, heat conductivity, temperature, heat flux density and the like, the geometric boundary of the unknown part is solved. Therefore, the inverse solution model has higher practicability than the forward solution model, and is the main method for analyzing the erosion problem of the blast furnace hearth at present.
To predict erosion boundaries, establishing an inverse solution by fourier's law in heat transfer is one of the reliable approaches. The traditional one-dimensional calculation model is easy to calculate and understand, but the calculation result has larger error and low precision; the three-dimensional model is too complicated and difficult. Therefore, compared with the prior art, the two-dimensional calculation model can greatly improve the analysis precision, has high practical application value and is the most practical method at present. The complexity and time consumption of the two-dimensional model are that a credible erosion boundary can not be obtained through one-time calculation, and the two-dimensional model can be obtained by iteration, search and approximation for multiple times of calculation. The conventional two-dimensional iteration method consumes too long time, and the grid division needs to be carried out again for each iteration, so that resources are greatly consumed, the rapid estimation of the obtained result in engineering is not facilitated, and meanwhile, common computing hardware cannot meet the computing requirement. Therefore, the two-dimensional rapid calculation method for the erosion boundary of the longitudinal section of the blast furnace hearth is provided.
Disclosure of Invention
In order to solve the technical problem, the embodiment of the invention provides a two-dimensional rapid calculation method for a blast furnace hearth erosion boundary longitudinal section under a fixed calculation domain grid, which specifically comprises the following steps:
the first step is as follows: the temperature of the outer boundary layer is determined.
The two-dimensional method of the invention aims at the longitudinal section of the blast furnace hearth. The existing thermocouple with known temperature is divided into an outer thermocouple and an inner parameter thermocouple, and the thermocouple close to the outer wall surface is called as an outer thermocouple and is marked as Pi,out(ii) a The thermocouple near the side of the iron-condensing layer is called inner-layer parameter thermocouple and is marked as Pi,in. According to the existing outer layer thermocouple Pi,outTemperature T by outer thermocouplei,outAnd coordinates, calculating and obtaining the temperature of the outer layer boundary by utilizing a linear interpolation method.
The second step is that: a structured grid of the initial computational domain is rendered. The coverage range of the calculation domain grid comprises a ferric gel layer and a solid wall surface. In order to save the calculation time and improve the calculation efficiency, the grid is fixed and only the position of the erosion line is changed along with the calculation. According to the blast furnace ironmaking characteristics, the calculation domain comprises two parts, namely, the solidified molten iron and the blast furnace wall, in the drawn grid, the boundary of the inner layer of the calculation domain is a solidified iron line with the temperature of 1150 ℃, and the outer layer is the blast furnace wall surface. The boundary position of the outer layer of the calculation domain is formed by an outer ring thermocouple Pi,outAnd determining the position. The calculation of the boundary position of the inner layer is based on the thermocouple P of the outer layeri,outThe position and the temperature are obtained by reverse extrapolation of a one-dimensional Fourier law. Thereby completing the determination of the computational domain grid.
The third step: and preliminarily determining the position of the erosion line. Selecting appropriate values and ranges, taking a series of hypothetical erosion linesAnd calculating, and artificially controlling to gradually advance from the inner boundary layer to the outer boundary layer in order to facilitate calculation and arrangement. According to different erosion line positions, different inner layer parameters of the thermocouple P can be obtained through calculation according to basic heat transfer science knowledgei,inThe calculated temperature corresponding to the position is recorded as Tical,in(ii) a Inner layer parameter thermocouple Pi,inThe actually measured temperature of the thermocouple corresponding to the position is recorded as Ti,in(ii) a Calculating to all T according to the stepsical,in>Ti,in. Mixing the above series of erosion lines and calculated value Tical,inAnd (4) finishing, and preliminarily estimating and conjecturing by a linear interpolation method to obtain an initial inner wall erosion line.
The fourth step: calculating a new set of T from the initial inner wall erosion lineical,inWill be compared with the actual Ti,inCalculating an error range, and when the numerical error of the temperature is within 1.5%, determining that the wall thickness is an actual value; and (3) performing correction calculation on the error range larger than 1.5%, wherein the correction method is the same as the third step, namely, firstly, assuming the positions of a plurality of erosion lines to obtain different temperature values corresponding to the positions of the thermocouples at the inner layer, and then estimating the estimated positions of the erosion lines by linear interpolation. And calculating the temperature of the inner-layer thermocouple according to the position of the erosion line, comparing the temperature with an actual value, judging that the temperature can be calculated within 1.5 percent, and otherwise, continuously repeating the calculation.
The fifth step: when all thermocouples P calculated from the erosion linei,inTemperature T corresponding to the positionical,inWith the actual value Ti,inWhen the error ranges of the two lines are within 1.5%, the line is considered as the required erosion line.
Has the advantages that: the invention can solve the technical problems that the erosion detection iteration method in the prior art is too long in time consumption, large in calculation amount, not beneficial to quick estimation of the obtained result in engineering and incapable of meeting the calculation requirements of common calculation hardware.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 is a schematic diagram of a computational domain grid of the present invention;
FIG. 2 is a schematic diagram of erosion line calculation and correction according to the present invention.
Detailed Description
Embodiments of the invention will be described in detail below with reference to the drawings, but the invention can be implemented in many different ways, which are defined and covered by the claims.
The computational domain structured grid is rendered as shown in fig. 1. The two-dimensional method of the invention aims at the longitudinal section of the blast furnace hearth. The method for calculating the fixed and unchangeable grid is adopted, and only the position of the erosion line changes along with calculation. According to the blast furnace ironmaking characteristic, the coverage area of the calculation domain grid comprises two parts, namely solidified molten iron and a blast furnace wall. In the drawn grid, the boundary of the inner layer is calculated to be a iron coagulation line with the temperature of 1150 ℃, and the outer layer is the wall surface of the blast furnace.
The two-dimensional method of the invention is aimed at the longitudinal section of the blast furnace hearth, and firstly, the temperature of the outer boundary layer is determined. The existing thermocouple with known temperature is divided into an outer thermocouple and an inner parameter thermocouple, and the thermocouple close to the outer wall surface is called as an outer thermocouple and is marked as Pi,out(ii) a The thermocouple near the side of the iron-condensing layer is called inner-layer parameter thermocouple and is marked as Pi,in. According to the existing outer layer thermocouple Pi,outTemperature T by outer thermocouplei,outAnd coordinates, calculating and obtaining the temperature of the outer layer boundary by utilizing a linear interpolation method.
A structured grid of the initial computational domain is rendered. The coverage range of the calculation domain grid comprises a ferric gel layer and a solid wall surface. In order to save the calculation time and improve the calculation efficiency, the grid is fixed and only the position of the erosion line is changed along with the calculation. According to the blast furnace ironmaking characteristics, the calculation domain comprises two parts, namely, the solidified molten iron and the blast furnace wall, in the drawn grid, the boundary of the inner layer of the calculation domain is a solidified iron line with the temperature of 1150 ℃, and the outer layer is the blast furnace wall surface. The boundary position of the outer layer of the calculation domain is formed by an outer ring thermocouple Pi,outAnd determining the position. The calculation of the boundary position of the inner layer is based on the thermocouple P of the outer layeri,outThe position and temperature are inverted by one-dimensional Fourier lawAnd (6) obtaining by pushing. Thereby completing the determination of the computational domain grid.
And preliminarily determining the position of the erosion line. And selecting proper values and ranges, taking a series of assumed erosion lines for calculation, and artificially controlling the erosion lines to gradually advance from the inner boundary layer to the outer boundary layer for the convenience of calculation and arrangement. According to different erosion line positions, different inner layer parameters of the thermocouple P can be obtained through calculation according to basic heat transfer science knowledgei,inThe calculated temperature corresponding to the position is recorded as Tical,in(ii) a Inner layer parameter thermocouple Pi,inThe actual temperature corresponding to the position is recorded as Ti,in(ii) a Calculating to all T according to the stepsical,in>Ti,in. Mixing the above series of erosion lines and calculated value Tical,inAnd (4) finishing, and preliminarily estimating and conjecturing by a linear interpolation method to obtain an initial inner wall erosion line.
Calculating a new set of T from the initial inner wall erosion lineical,inWill be compared with the actual Ti,inCalculating an error range, and when the numerical error of the temperature is within 1.5%, determining that the wall thickness is an actual value; and performing correction calculation on the error range larger than 1.5%.
As shown in fig. 2, the yellow line is a neighboring two calculated erosion lines that remain unchanged, and the red area is a two erosion line and a changed area of the outer boundary containing area.
When all thermocouples P calculated from the erosion linei,inTemperature T corresponding to the positionical,inWith the actual value Ti,inWhen the error ranges of the two lines are within 1.5%, the line is considered as the required erosion line.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (5)
1. A two-dimensional rapid calculation method for erosion boundaries of longitudinal sections of blast furnace hearths is characterized by comprising the following steps:
step 1: firstly, determining the temperature of an outer boundary layer;
step 2: drawing a structured grid of an initial calculation domain, wherein the boundary of the inner layer of the calculation domain is a ferrogel line, and the outer layer is the wall surface of the blast furnace;
and step 3: preliminarily determining the position of an inner wall erosion line;
and 4, step 4: calculating to obtain a group of inner layer parameter thermocouples P from the preliminarily determined inner wall erosion linesi,inTemperature T corresponding to the positionical,inCalculating Tical,inAnd inner layer parameter thermocouple Pi,inCorresponding actual temperature value Ti,inWhen all thermocouples P are presenti,inTemperature T corresponding to the positionical,inAnd the actual temperature value Ti,inWhen the errors are smaller than the threshold value, the preliminarily determined inner wall erosion line is the required inner wall erosion line; repeating steps 3 and 4 when the error is greater than the threshold.
2. The two-dimensional rapid calculation method for the erosion boundary of the longitudinal section of the blast furnace hearth according to claim 1, characterized in that in the step 1, the thermocouples with the known existing temperature are divided into outer layer thermocouples and inner layer parameter thermocouples, and the thermocouple at the side close to the outer wall surface is called as outer layer thermocouples and is marked as Pi,out(ii) a The thermocouple near the side of the iron-condensing layer is called inner-layer parameter thermocouple and is marked as Pi,in(ii) a According to the existing outer layer thermocouple Pi,outTemperature T by outer thermocouplei,outAnd coordinates, calculating and obtaining the temperature of the outer layer boundary by utilizing a linear interpolation method.
3. The two-dimensional rapid calculation method for erosion boundary of longitudinal section of blast furnace hearth according to claim 1, characterized in that in step 2, the calculation of the boundary position of inner layer is based on outer layer thermocouple Pi,outThe position and the temperature are obtained by reverse extrapolation of a one-dimensional Fourier law.
4. The two-dimensional rapid calculation method for the erosion boundary of the longitudinal section of the blast furnace hearth according to the claim 1, wherein in the step 3, the step of preliminarily determining the position of the erosion line comprises the following steps:
step 3.1: taking a series of assumed erosion lines, and gradually advancing the positions of the selected erosion lines from the inner boundary layer to the outer boundary layer;
step 3.2: calculating to obtain different inner layer parameters of the thermocouple P according to different erosion line positionsi,inThe temperature corresponding to the position is recorded as Tical,inUp to all Tical,in>Ti,in；
Step 3.3: mixing the above series of erosion lines and calculated value Tical,inAnd (4) obtaining an initial inner wall erosion line through preliminary prediction and conjecture of a linear interpolation method.
5. The method for rapidly calculating the erosion boundary of the longitudinal section of the blast furnace hearth according to the claim 1, wherein in the step 4, the threshold value is 1.5%.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111854668A (en) * | 2020-08-25 | 2020-10-30 | 中冶赛迪工程技术股份有限公司 | Blast furnace lining thickness calculation device and method based on distributed optical fiber temperature measurement |
| CN113111549A (en) * | 2021-03-31 | 2021-07-13 | 北京首钢股份有限公司 | Method and system for modeling erosion model after pouring and repairing blast furnace hearth |
| CN116362085A (en) * | 2023-03-31 | 2023-06-30 | 东北大学 | Hearth lining erosion morphology identification method based on cooling wall heat flow intensity |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111854668A (en) * | 2020-08-25 | 2020-10-30 | 中冶赛迪工程技术股份有限公司 | Blast furnace lining thickness calculation device and method based on distributed optical fiber temperature measurement |
| CN113111549A (en) * | 2021-03-31 | 2021-07-13 | 北京首钢股份有限公司 | Method and system for modeling erosion model after pouring and repairing blast furnace hearth |
| CN113111549B (en) * | 2021-03-31 | 2024-02-27 | 北京首钢股份有限公司 | Erosion model modeling method and modeling system for casting repaired blast furnace hearth |
| CN116362085A (en) * | 2023-03-31 | 2023-06-30 | 东北大学 | Hearth lining erosion morphology identification method based on cooling wall heat flow intensity |
| CN116362085B (en) * | 2023-03-31 | 2024-01-30 | 东北大学 | Hearth lining erosion morphology identification method based on cooling wall heat flow intensity |
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