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瞬态平面热源法加厚探头的数值模拟研究

中国测试 2024年第7期50卷 138-146页

作者：胡铮程树森北京科技大学冶金与生态工程学院北京100083

瞬态平面热源法(TPS)的理论假设限制了该方法的使用场景,为此该文研究了加厚探头的导热系数测量精度并提出热容修正模型。利用COMSOL Multiphysics软件建立5501型探头的三维模型和增加镍丝厚度形成的加厚探头模型,根据模拟得出的温度历... 详细信息

瞬态平面热源法(TPS)的理论假设限制了该方法的使用场景,为此该文研究了加厚探头的导热系数测量精度并提出热容修正模型。利用COMSOL Multiphysics软件建立5501型探头的三维模型和增加镍丝厚度形成的加厚探头模型,根据模拟得出的温度历史数据绘制探头温升曲线,结合无量纲时间函数,迭代拟合得出待测样品的导热系数,并探讨加热功率及加热时间对加厚探头测量精度的影响。结果表明:由加厚模型得出的导热系数相对误差显著增大;随着加热功率的提高,材料导热系数测量误差减小;热容修正模型在测量不同材料时的修正幅度,与探头比热容相对待测材料比热容的大小呈正相关;使用热容修正模型后探头测量导热系数的相对误差在1.5%以内。研究证明提出的加厚探头结构及修正模型能够满足TPS法对导热系数测量精度的要求,同时提高探头强度使其适应较为复杂的使用环境。

关键词：瞬态平面热源法热传导导热系数数值模拟

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铝粒尺寸及入炉高度对运动轨迹的影响

炼钢 2024年第3期40卷 39-49页

作者：张勇刘勇彭集棚程树森北京科技大学冶金与生态工程学院北京100083

二次精炼过程中,铝是钢液进行脱氧及合金化的主要物料之一,但纯铝的密度小于钢液,能否穿越渣层与钢液接触及接触时间对铝的脱氧效果和钢中溶解铝的含量有直接影响。在忽略铝的熔化、溶解及化学反应的情况下,通过对铝粒运动过程受力分析... 详细信息

二次精炼过程中,铝是钢液进行脱氧及合金化的主要物料之一,但纯铝的密度小于钢液,能否穿越渣层与钢液接触及接触时间对铝的脱氧效果和钢中溶解铝的含量有直接影响。在忽略铝的熔化、溶解及化学反应的情况下,通过对铝粒运动过程受力分析,建立铝粒在气-渣-钢相内的三维运动数学模型,明晰铝粒尺寸及入炉高度对铝粒运动轨迹的影响。结果表明:在渣层厚度为70 mm且入炉高度为1~1.5 m的情况下,1 mm和5 mm的铝粒在渣钢界面处波动;入炉高度为1 m时,粒径为10 mm的铝粒停留在渣钢界面处,但在入炉高度为1.5 m及以上时可以进入钢液;20 mm及以上尺寸的铝粒可以进入钢液。在入炉高度为1 m时、30 mm尺寸的铝粒在钢液中的停留时间与深度相较于20 mm的基础上分别增加22.86%和50.00%;在铝粒尺寸为20 mm时、入炉高度为1.5 m时的铝粒在钢液中的停留时间与深度在1 m的基础上分别增加5.71%和10.00%。增加钢渣界面张力、减小钢铝界面张力或增加渣铝界面张力有利于铝粒进入钢液,而铝粒的尺寸大于20 mm,界面张力对铝块运动几乎没有影响;增大密度会使钢芯铝在钢液中停留更长时间,有利于钢液脱氧。

关键词：铝粒运动数学模型渣钢界面曳力模型界面张力

Optimization for the structure of BF hearth bottom and the arrangement of thermal couples

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Journal of University of Science and Technology Beijing 2006年第6期13卷 497-503页

作者： Hongbo Zhao shusen cheng Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijing 100083 China

The hearth of ＂heat transfer method＂ and the ceramic cup synthetic hearth bottom of ＂heart isolation method＂ are two most popular designs for blast furnace （BF）. Although there are successful real examples, some disadvantages, for instance large heat loss and high cost, still exist for these designs. According to the theory of heat transfer, based on the calculation of temperature distribution of the hearth bottom, it is elucidated that all brick layers at the hearth bottom may not be considered as the only reason why different structures exhibited different temperature distributions although total heat resistance is the same, and then based on the effect of hot metal and cold water on different temperature distribution ranges, the concepts of ＂heat resistance＂ and ＂cooling enhancement＂ are put forth. Based on this, the disadvantages and the factors affecting temperature distribution, of the two types of hearth bottoms were illustrated. On the basis of these analyses, a novel structure for BF hearth bottom designing that can easily form ＂self-protecting＂ slag layer stably, called ＂the method of gradient brick layout that has an optimum combination of cooling enhancement and heat resistance＂ was proposed; it can not only prolong the hearth bottom longevity but also reduce the cost and heat loss. Also, the optimum arrangement of thermal couples in hearth bottom was suggested based on the previous studies on erosion prediction carried out by the author.

关键词： blast furnace hearth bottom longevity design erosion

Mathematical model of flow characteristic in multi-strand continuous casting tundishes

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Acta Metallurgica Sinica(English Letters) 2009年第4期22卷 297-307页

作者： Hongwei PAN shusen cheng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

In this paper, the subject of mathematical model is a series of math expressions, which is used to calculate different regions＇ volume fraction and analyze flow characterization in multi-strand tundish. But research about mathematical model for multi-strand tundish is few, and so far, there has been no acknowledged math model for multi- strand tundish to describe its flow characteristic. If Sahai＇s model, which is originally proposed for the case of single-strand tundish （proposed in reference, and this model is widely used in the world）, is applied to describe flow feature in multi-strand tundish, the calculation results would be unreasonable. Based on the data of watermodel experiment results, the sum of each strand＇s dead region＇s volume fraction is bigger than 100%, and this obviously doesn＇T agree with reality; and the value of dead region＇s volume fraction is calculated to be minus according to mathematical simulation results data in another case. What＇s more, Sahai＇s model does not propose the standard of plotting the RTD-curve, and this makes scholars around the world can＇t achieve consensus of views about plotting RTD-curve. And the model doesn＇t consider the bypass flow and can＇t calculate its volume fraction, but bypass flow is critical to tundish metallurgy. And through Sahai＇s model, the calculation result of plug flow region＇s volume fraction is also not reasonable, because the model doesn＇t well describe the essence of plug flow. So these suggest that it is not reliable to apply Sahai＇s single-strand tundish model to multi-strand tundish case. Then a new model is attempted to propose in this paper for your discussion. In the new model, the standard of plotting RTD curve is definitely proposed, and relative calculation method is also proposed; and the feature of dead region is carefully studied and the model proposes a new method to calculate its volume fraction, and the calculation formula about its volume fraction can be adjustable according the actu

关键词： Tundish Residual time distribution (RTD) Bypass flow Dead region Water-model Mathematical simulation

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连铸过程长水口理论吹氩流量分析

中国冶金 2024年第3期34卷 75-83页

作者：张育萌程树森冯永平李积鹏北京科技大学冶金与生态工程学院北京100083 酒钢集团宏兴钢铁股份有限公司碳钢薄板厂甘肃嘉峪关735100

连铸过程水口间接缝容易吸入空气,使得钢液二次氧化。生产中采用长水口吹氩来防止空气吸入,但吹氩流量控制不当会导致铸坯缺陷。水口吸入空气是由于水口内部压力低于大气压,目前水口吹氩流量控制与工艺参数调整并未建立联系。基于连续... 详细信息

连铸过程水口间接缝容易吸入空气,使得钢液二次氧化。生产中采用长水口吹氩来防止空气吸入,但吹氩流量控制不当会导致铸坯缺陷。水口吸入空气是由于水口内部压力低于大气压,目前水口吹氩流量控制与工艺参数调整并未建立联系。基于连续性方程和伯努利方程建立钢包到中间包的质量-能量守恒数学物理模型,研究长水口钢液流动时水口内压力分布,总结不同出口条件及吹氩流量下水口内流体分布状态,同时计算不同条件下的理论吹氩流量;探究浇注时间、拉坯速度、滑动水口及长水口直径、长水口浸入深度、吹氩流量对水口内压力分布的影响。研究发现,提高拉速、增加长水口浸入深度、减小滑动水口和长水口直径以及提高水口吹氩流量有利于减小水口内负压;当提高拉速、增加长水口浸入深度或增大水口直径时应当加大吹氩流量;使用喇叭型长水口可以降低出口钢液速度,其内部压力小于直筒型长水口,吹氩时其水口出口钢液速度增加量比直筒型长水口小。研究结果为制定长水口吹氩量提供了理论基础。

关键词：长水口伯努利方程连续性方程压力分布吹氩流量

Mathematical simulation of hot metal desulfurization during KR process coupled with an unreacted core model

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International Journal of Minerals,Metallurgy and Materials 2022年第4期29卷 758-766页

作者： Yanyu Zhao Wei Chen shusen cheng Lifeng Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

A three-dimensional mathematical model was established to predict the multiphase flow,motion and dispersion of desulfurizer particles,and desulfurization of hot metal during the Kanbara reactor(KR)*** turbulent kinetic energy-turbulent dissipation rate(k-ε)turbulence model,volume-of-fluid multiphase model,discrete-phase model,and unreacted core model for the reaction between the hot metal and particles were *** measured sulfur content of the hot metal with time during the actual KR process was employed to validate the current mathematical *** distance from the lowest point of the liquid level to the bottom of the ladle decreased from 3170 to2191 mm when the rotation speed increased from 30 to 110 r/min,which had a great effect on the dispersion of desulfurizer *** critical rotation speed for the vortex to reach the upper edge of the stirring impeller was 70 r/min when the immersion depth was 1500 *** desulfurization rate increased with the increase in the impeller rotation speed,whereas the influence of the immersion depth was relatively *** for different rotation parameters on the desulfurization rate constant and turbulent energy dissipation rate were proposed to evaluate the variation in sulfur content over time.

关键词： desulfurization unreacted core model desulfurizer dispersion KR process fluid flow

Quantitative analysis of steel and iron by laser-induced breakdown spectroscopy using GA-KELM

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Plasma Science and Technology 2019年第3期21卷 167-173页

作者： Yaguang MEI shusen cheng Zhongqi HAO Lianbo GUO Xiangyou LI Xiaoyan ZENG Junliang GE School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Wuhan National Laboratory for Optoelectronics Laser and Tera-Hertz Technology Division Huazhong University of Science and Technology Institute for Science and Technology Information and Strategy Central Iron and Steel Research Institute

According to the multiple researches in the last couple of years, laser-induced breakdown spectroscopy(LIBS) has shown a great potential for rapid analysis in steel ***, the accuracy and precision may be limited by complex matrix effect and selfabsorption effect of LIBS seriously. A novel multivariate calibration method based on genetic algorithm-kernel extreme learning machine(GA-KELM) is proposed for quantitative analysis of multiple elements(Si, Mn, Cr, Ni, V, Ti, Cu, Mo) in forty-seven certified steel and iron ***, the standardized peak intensities of selected spectra lines are used as the input of ***, the genetic algorithm is adopted to optimize the model parameters due to its obvious capability in finding the global optimum solution. Based on these two steps above, the kernel method is introduced to create kernel matrix which is used to replace the hidden layer's output matrix. Finally, the least square is applied to calculate the model's output weight. In order to verify the predictive capability of the GA-KELM model, the R-square factor(R^2), Root-meansquare Errors of Calibration(RMSEC), Root-mean-square Errors of Prediction(RMSEP) of GAKELM model are compared with the traditional PLS algorithm, respectively. The results confirm that GA-KELM can reduce the interference from matrix effect and self-absorption effect and is suitable for multi-elements calibration of LIBS.

关键词： laser-induced breakdown spectroscopy(LIBS) alloy elements calibration genetic algorithm-kernel extreme learning machine(GA-KELM)

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柱流多旋顶燃式热风炉燃烧过程数值仿真

工业炉 2024年第4期46卷 1-7页

作者：彭集棚张勇程树森刘世聚刘力铭刘力源北京科技大学冶金与生态工程学院河南省豫兴热风炉工程技术有限公司

建立了柱流多旋顶燃式热风炉空煤气燃烧和NOx排放的三维物理数学模型，对炉内燃烧速度场、温度场、浓度场及NOx排放进行了仿真研究。结果表明：燃烧室出口截面速率分布均匀；通过设置不同倾斜角度的混合烧嘴，使得炉内O2和CO混合充分，... 详细信息

建立了柱流多旋顶燃式热风炉空煤气燃烧和NOx排放的三维物理数学模型，对炉内燃烧速度场、温度场、浓度场及NOx排放进行了仿真研究。结果表明：燃烧室出口截面速率分布均匀；通过设置不同倾斜角度的混合烧嘴，使得炉内O2和CO混合充分，燃烧效果好，燃烧室出口截面的最高CO浓度为33.2×10-6，最高O2浓度为19.4×10-6，最高NOx浓度为14.8×10-6；火焰在混合烧嘴内形成，在扩张段区域消失，火焰长度较短；燃烧室出口截面温度分布均匀，最大温差为16 K。

关键词：顶燃式热风炉流场浓度场温度场数值仿真

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顶燃式热风炉钢壳受力及变形分析

过程工程学报 2017年第4期17卷 771-778页

作者：颜坤程树森北京科技大学冶金与生态工程学院北京100083

通过建立顶燃式热风炉炉壳弹塑性模型,研究了盲板力作用下热风炉炉壳的受力状态及变形情况.结果表明,在内部气体压力作用下,热风炉炉壳及热风总管变形弯曲挤压热风支管,导致热风炉炉体、总管与支管相交线附近炉壳出现应力集中,送风期热... 详细信息

通过建立顶燃式热风炉炉壳弹塑性模型,研究了盲板力作用下热风炉炉壳的受力状态及变形情况.结果表明,在内部气体压力作用下,热风炉炉壳及热风总管变形弯曲挤压热风支管,导致热风炉炉体、总管与支管相交线附近炉壳出现应力集中,送风期热风炉热风出口顶部与底部发生塑性变形,热风炉出口附近钢壳在顶部、底部附近所受Z向拉应力及左右两侧附近所受Y向压应力的作用下向两侧拉伸并沿高度方向压缩,近似成椭圆形;送风期比燃烧期热风炉出口炉壳变形更明显,热风出口处钢壳在操作周期中的反复变形影响热风炉的寿命及稳定性.

关键词：顶燃式热风炉热风炉炉壳弹塑性应力模型受力分析操作周期