铸件定向凝固过程的数值模拟

 本文探讨大温度梯度下铸件定向凝固过程数值模拟的一些规律性。 为了提高计算精度,讨论了在大温度梯度条件下热传导方程中项对计算结果的影响。对如何处理凝固潜热,铸件-铸型界面热性质和初始条件等问题也进行了分析。 对同一铸件,在初始条件、边界条件和热物理参数相同的情况下,采用有限差分和有限元两种方法进行计算,并比较其优缺点。

NUMERICAL SIMULATION OF THE DIRECTIONAL SOLIDIFICATION OF CASTINGS

Some rules of computer numerical simulation for the directional solidification with steep temperature gradient have been found out.In order to improve the accuracy in the numerical simulation for the directional solidification with steep temperature gradient, the effect ofin heat transfer equation on the computational results is discussed and how to treat the heat of fusion, thermal property of the casting/mould interface and initial conditions etc. are analyzed.Two computation methods-finite difference and finite element methods-are used for the same test ingot with the identical initial conditions, boundary conditions and thermophysical parameters. The advantages and shortcomings of the both methods are compared.