论文部分内容阅读
铸件凝固过程数值模拟是计算机在铸造中应用的重要内容之一,为优化铸造工艺设计,提高和确保铸件质量,降低生产成本,提高劳动生产率提供了科学的手段。本文应用有限元法,对铝合金铸件凝固数值模拟进行了初步的研究。本文的铝合金铸件凝固过程数值模拟采用了热传导模型,利用伽辽金加权余量法建立有限元格式。凝固潜热的处理采用了假想热流法(ficitiousheatflowmethod)。考虑了铸造中可能遇到的各种边界条件。为了提高研究起点,本程序的前后处理采用了美国SDRC公司的商品化软件IDEAS中的相应模块。该软件能够建立复杂形体的有限元模型,并输出相关的数据文件。利用自行开发的前处理接口程序实现与主程序的连接。最后,应用本软件对两种条件下的铝合金金属型铸件的凝固过程进行了数值模拟,得到了铸件凝固过程中温度场分布,并用多种判据对该条件下铸件是否会出现缩松(孔)缺陷进行了预测。通过数值模拟结果与有关文献给出的铸件指定部位的冷却测试曲线的对比,验证了本程序的准确度。
The numerical simulation of casting solidification process is one of the important applications of computer in casting. It provides a scientific method for optimizing casting process design, improving and ensuring casting quality, reducing production cost and improving labor productivity. In this paper, finite element method is used to study the numerical simulation of solidification of aluminum alloy castings. The numerical simulation of the solidification process of the aluminum alloy castings in this paper uses the heat conduction model, and the finite element method is established by using the Galerkin weighted residual method. The latent heat of solidification is treated by the ficitious heat flow method. Consider the various boundary conditions that may be encountered in casting. In order to improve the research starting point, the preprocessing of this program adopts the corresponding module in the software IDEAS of American SDRC Company. The software can create a complex body of the finite element model, and output related data files. Using self-developed pre-processing interface program to achieve the connection with the main program. Finally, the software was used to simulate the solidification process of the aluminum alloy metal castings under both conditions. The temperature field distribution during the solidification of the castings was obtained and the castings under this condition were subjected to the shrinkage ( Hole) defects were predicted. The accuracy of this program is verified by comparing the numerical simulation results with the cooling test curves of the designated parts of castings given in the literature.