共查询到20条相似文献,搜索用时 62 毫秒
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根据成都无缝钢管厂水平连铸的生产实践,建立了较大断面铸坯凝固传热过程数学模型。通过数学模拟仿真,找出铸坯在结晶器和喷水区内凝固传热过程的温度场变化,凝壳生长规律及液芯长度等与浇注参数(拉速,浇注温度)的关系。 相似文献
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结晶器内连铸小方坯凝固过程及应力分布的有限元数值模拟 总被引:8,自引:1,他引:7
建立了结晶器内连铸坯凝固传热及弹塑性应力分析有限元数学模型,模型中引入与气隙相关的传热边界条件修正平均热流量方程考虑了材料力学性能,屈服函数随温度和应变速率的变化,研究了角度气隙对坯壳凝固行为和力学行为的影响。 相似文献
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圆坯连铸温度场模拟 总被引:4,自引:0,他引:4
耦合温度场和流场 ,建立了圆坯连铸铸坯温度场的二维稳态柱坐标数学模型。用该模型模拟了国内某钢铁公司Φ178mm圆坯连铸铸坯内温度场分布 ,以渐变色形式模拟显示了圆坯连铸铸坯中心断面温度场分布 ;在温度场的基础上 ,模拟了铸坯凝固壳的厚度变化 ;模拟显示了结晶器内的钢液流动 ;采用铸坯传热数学模型在不同拉速及过热度下进行计算 ,系统分析了拉速及过热度对凝固末端位置、出结晶器坯壳厚度的影响。凝固末端位置的计算结果与现场实测结果一致 ,从而证明了模型的合理性。本研究模拟出的温度场分布和铸坯坯壳厚度 ,为优化工艺参数 ,提高铸坯质量提供了理论依据 相似文献
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ZHU Xianhua DONG Zengzhang SU Junyi Xi''''an Jiaotong University Xi''''an China 《金属学报(英文版)》1990,3(12):384-390
The solidification process of a horizontally continuously cast gray iron bar of 4.6cm in diame-ter was modelled.The function describing the distribution of heat flux at the internal surfaceof graphite sleeve,which was equal to that on the surface of the iron bar,was inversely derivedusing numerical calculation from the temperature distribution in the sleeve measured in realproduction.By using the distribution of heat flux as a boundary condition on the surface of theiron bar,the numerical simulation on solidification of the iron bar taking longitudinal heatconduction into account was made.The profile of solidification front obtained from the numer-ical simulation was approximately coincident with that in real production.In addition,thequantitative relationships of the thickness of solidified shell at the exit of the mold to the maintechnological parameters,including the temperature of liquid iron at the entrance of the mold,the moving speed of the bar and the intensity of water cooling,were obtained from the numeri-cal simulation. 相似文献
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应用自行开发的铸件充型及凝固模拟系统,对铝合金石膏型精密铸件的凝固过程进行了数值模拟。采用自行设计制备的多通道自动测温装置,对所模拟的铸件进行现场测温。为了提高模拟精度,对铸件铸型热物性参数进行了实测,并采用最小二乘法进行拟合。通过计算机模拟预测了铸件的缩孔区,分析了铸件缺陷产生的原因,提出了合理的工艺方案,消除了铸件内缩孔的发生。实验验证的结果表明,数值模拟结果与测试值拟合较好 相似文献
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COUPLED NUMERICAL SIMULATION OF STEEL FLOW AND SOLIDIFICATION IN SOFT-CONTACT BILLET MOLD 总被引:1,自引:0,他引:1
A.Y. Deng J.C. HeKey Laboratory for Electromagnetic Processing of Materials Ministry of Education Northeastern University Shenyang China 《金属学报(英文版)》2002,15(5):471-478
A coupled model including electromagnetic field, fluid dynamic, heat transfer and solidification, is developed and applied to the numerical simulation of steel flow and solidification in a 100mm×100mm soft-contact mold. In this study, the 3D finite difference method and non-staggered grid system for fluid flow with body fitted coordinate were employed. Numerical results show that the electromagnetic force mainly affects the steel flow at upper part of mold, especially in the vicinity of meniscus. There exist upward flows covering the surfaces of the billet due to the concentration of electromagnetic force on the upper part of the billet. This flows join together and form a downward flow near the SEN, so a distinct circulating flow zone is formed at upper part of mold. After applying electromagnetic force, the steel velocity is improved and the temperature is raised. The strong stirring of electromagnetic force on liquid steel makes the kinetic energy on free surface increase. It is clearly seen that the 相似文献
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镍基高温合金多叶片定向凝固过程数值模拟 总被引:2,自引:0,他引:2
建立了基于Monte Carlo法的射线追踪模型,并用来动态处理定向凝固抽拉过程中多叶片间以及叶片与加热炉间的辐射换热过程.模型中考虑了抽拉速度、加热炉几何尺寸等影响,研究了2种抽拉速度下的温度分布.得到的温度采样点冷却曲线与实际冷却曲线进行了对比并得到了较好的结果.多叶片条件下,冷却区叶片靠近炉壁的温度低于同一水平线上靠近炉腔中心部分的温度.抽拉速度为7.0 mm/min时等温线的斜率高于抽拉速度为4.5 mm/min时的斜率.炉腔的几何尺寸对凝固过程温度分布有重要影响. 相似文献
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垂直定向凝固条件下通道偏析形成过程的数值模拟 总被引:4,自引:0,他引:4
建立了描述合金凝固过程热-溶质对流和宏观偏析形成过程的数学模型。模型中耦合求解了凝固过程中质量、动量、能量和溶质守恒方程;同时,基于固液两相区中温度和成分的耦合关系建立了固相分数场的更新方法。利用该模型模拟了底部冷却的二维矩形区域内Fe-C合金凝固过程中通道偏析的形成和发展过程。模拟结果表明,垂直定向凝固条件下通道偏析形成于液相线前沿附近,而不是两相区内部。这一结果很好地支持了文献中基于实验观察提出的通道偏析形成机理。 相似文献
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J.X. Zhou R.X. Liu L.L. Chen D.M. Liao H. S. Wei 《金属学报(英文版)》2005,18(6):724-730
Numerical simulation of casting's mold filling process is the main and the most important aspect of the foundry CAE technology. But it is time-consuming; it may take dozens of hours or several days. While with the development of computer hardware, numerical simulation of casting' s mold filling process has made rapid progress. The simulation results, therefore, have become more and more practical. This study tries to find some clues of the computational time of mold filling process. Firstly, this paper introduces mathematic model and the basic route of numerical simulation of casting's mold filling process. Then the computational time of mold filling process has been carefully studied, and some new and useful results have been gained from the study of the computational time. Finally, this paper has given some real applications of numerical simulation of casting's mold filling process. 相似文献
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NUMERICAL SIMULATION OF CASTING''''S MOLD FILLING PROCESS 总被引:1,自引:0,他引:1
J.X. Zhou R.X. Liu L.L. Chen D.M. Liao H.S. Wei State Key Lab of Die Mold Technology Huazhong University of Science Technology Wuhan China 《金属学报(英文版)》2005,18(6)
1. Introduction Numerical simulation of casting's mold filling and solidification process is a technology to recon- struct and advance the traditional foundry industry by using computer technique, and it has an important effect on reducing the product cos… 相似文献
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NUMERICAL SIMULATION OF ROUND TO OVAL ROLLING PROCESS 总被引:5,自引:0,他引:5
Y. W. Wang Y. L. King D. H. Yuan S. G. Liu Z. Y. Yu ) University of Science Technology Beijing Beijing China ) Daye Special Steel Co. Huangshi China 《金属学报(英文版)》2000,13(2):428-433
1.IntroductionInthebarrollingprocess9ovalpassiswidelyused.Averycomplexthree--dimensionalInaterialflowtakesplaceinthepass.DuetothedifficLiltyofdevelopingtheoreticalanalysisforthree--dimensionalplasticdeformation,mosteffortsmadeonthissubjecthavebeeneitherempiricaloreXPerimental.Recently,withthedevelopmentofcomputers,thefiniteelementmethodhasbeenusedforthree--dimensionalrollingprocesssimulation.aam-etal.,simulatedsingleandmulti--passshaperollingusingfiniteandslabelementmethodll--3].Glowackietal… 相似文献