双辊连续铸轧工艺中流场、温度场和热应力场的数值计算

分析旋转状态铸辊内部传热过程特点的基础上,建立了熔池和铸辊混合区域的整体数学分析模型,并实现了整体模型的耦合求解.计算结果揭示了双辊法连续铸轧过程熔池内流场、凝固温度场及铸辊内温度场、热应力场的特点.     

NUMERICAL SIMULATION OF CASTING PROCESS

1.IntroductionThemodellingofcasting,whichmeansmostlycomputernumericalsimulationofcast...lug,isaimedatanalysingpracticalfoundryproceduresundercomputervirtualenvironment,includingfillingprocess,solidificationprocessandstressdistributionofcasting.Withthehelpofthespecialtechnique,itbecomeseasytoevaluatetheinfluenceofmajorfactorsandpredictcastingdefects.Therefore,thepowerfultoolcanbeadoptedtooptimizefoundrytechnologyandreducecastingdefects.Foundrynumericalsimulationresearchbeginsin1962,andhasagreat…     

SIMULATION OF THE TWIN ROLL STAINLESS STRIP CASTING PROCESS

1. IntroductionTwin roll stainless strip casting' process which can directly cast a thin strip with thickness less than 10mm from a molten metal pool is being researched by industrious workersall over the world. Compared with the conventional continuous casting, this process caneliminate the expansive and complex hot-rolling facilities, and can reduce both the capitalinvestmellt and the cost of production. Among various processes under development, thetwin-roll strip casting is revealed as the…     

铝带坯连续铸轧凝固过程的数值模拟

推导了二维传热的焓式有限元控制方程，开发了准三维有限元计算程序，并用该程序分析了太原铝厂双辊倾式铝带铸轧机在稳定生产条件下，各工艺参数间的关系及提高铸轧机生产能力的途径，本程序具有影响随时输出金属在铸轧区状态的功能，可用于生产过程中的动态跟踪。     

连铸中间包内钢液流动与传热耦合过程的计算机模拟

在开发描述中间包全内钢度流动与热三维耦合数学模型的基础上，对实际中间包内的流动和传热和过程进行了计算机模拟仿真研究，考察有了／无流动控制情况下，自然热对流对中间包内钢液流动行为的影响，对流动控制装置的功能进行了分析与讨论。     

EXPERIMENTAL RESEARCH AND NUMERICAL SIMULATION OF MOLD TEMPERATURE FIELD IN CONTINUOUS CASTING OF STEEL

Mold is the heart of the continuous casting machine. Heat transfer and solidification in a water cooled mold are the most important factors during the continuous casting of steel. For studying the temperature distribution of a mold wall, a simulated apparatus of mold was designed and experiments were performed by it. The measured results indicated that the mold wall temperature approaches the temperature of cooling-water. An equivalent thermal-conductivity coefficient was proposed and deduced on the basis of the conclusion of the experiments. This coefficient was applied to solve the heat transfer between the melt and cooling water, and to characterize the heat transfer capacity of the mold. By this equivalent thermal-conductivity coefficient, it is very easy and convenient to numerically simulate the solidification process of continuous casting. And the calculation results are in agreement with the experiments. The effects of casting speed and water flow rate on the mold temperature field were also discussed.     

电磁铸造大板坯半连铸过程温度场的数值模拟

Al的电磁铸造为半连续铸造过程，它的数学模型是空间非稳态非齐次热传输方程,提出并证明了以t时刻板坯占有的空间作为计算域，采用三维非稳态热传导方程，计算下一时刻（t＋△t）的温度场，并将温度场的位置随拉坯速度v的方向移动v△t，然后．将顶部空缺的v△t空间由浇注的金属熔液充满，此时的温度场即t＋△t时刻板坯行进位置的温度场.由于三维非稳态热传导方程具有稳定收敛的计算格式，所编制的软件可通用于三维非稳态热传输过程.模拟了1860mm×510mmAl合金大板坯，与文献已有的实测结果相比较，基本吻合.模拟结果表明，在板坯表面液柱高度相同的情况下．拉坯速度越大，液穴越深     

双辊薄带连铸熔池液面波动物理模拟

设计了一个双辊薄带连铸机动态物理模拟实验装置，利用超声波浪高仪对双辊熔池液面波动进行了实验测定。重点研究了不同水口结构、拉速（转速）、熔池高度以及插入深度等参数对熔池内液面波动的影响，从而为优选出满足双辊薄带连铸布流要求的水口结构尺寸提供依据。     

TIG焊接熔池中的流体流动及传热过程的数值模拟

本文建立了运动电弧作用下三维TIG焊接熔池中的流体流动及传热过程的数学模型。该模型同时考虑熔池内部液态金属的对流、传导和熔池外部的固体导热,克服了雷卡林公式和纯导热数值解将焊接热过程当作纯粹固体热传导问题的局限性,扩展了电弧固定时的二维熔池传热模型。根据该模型得出的计算结果和实验测试结果吻合程度良好。     

铝合金石膏型精密铸件凝固过程数值模拟与实验验证

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