精确成形制造中的高梯度特征与数值模拟的发展趋势

High - gradient Modeling and Typical Simulation Tech- nique in Net Shape Forming

精确成形制造是尽可能地精确控制材料的外部形状和内部组织结构,将材料加工成各种零部件及成品的新的工艺手段。其工艺过程的数值模拟表现出一系列复杂的特征,其中局部高梯度和多尺度耦合是最主要的问题。重点介绍处理这一问题的思路和方法,包括高梯度问题的函数描述、动点有限元方法、自适应有限元—无网格耦合方法。并指出处理高梯度问题的研究课题和技术关键。

Net shape processing through phase -change or deformation, which seeks to produce high quality products requiring minimal post -processing, can provide performance and cost benefits in manufacturing. The modeling and simulation of processes correctly for predictive capability of performance and producibility have become necessary. The process of netshape is characterized by local high gradient, coupling of multi -physical fields, large scale of computation, evolutive process of constitutive behaviors, high nonlinearity, multi - scale of size. The main purpose of this paper is to explore the strategy to treat this kind of characteristics mathematical expression of high gradient phenomenon, moving finite element method, adaptive FEM -Meshless method. Finally, the relative academic topics and key points are outlined.