金属增材制造的多物理场物质点有限元法

Multi-physics finite element-material point method for metal additive manufacturing

金属增材制造过程涉及复杂的热-流-固强耦合问题,对数值模拟算法的精度和效率提出了巨大的挑战。针对该问题,本文提出了多物理场物质点有限元法。该方法采用结构化背景网格、有限单元和物质点离散求解各物理场,通过分区求解和界面耦合的方式实现热-流-固耦合求解。对于潜在熔化区域和未发生熔化的区域,分别采用物质点和有限元离散,结合了两者在求解材料特大变形和小变形问题上的各自优势,能够在保证计算精度的前提下有效提升计算效率。数值算例表明了本文算法的热-流-固多场耦合计算精度、相比于已有算法的高效性以及物质点和有限元离散区域界面处温度和应力的连续性。本文工作为金属增材制造过程多物理场耦合问题提供了一种高效的数值模拟方法。

The intricacies of thermo-fluid-solid interactions greatly challenge the numerical methods for metal additive manufacturing processes.We propose a multi-physics finite element-material point method to address this problem.The method employs a structured background grid,finite elements,and material points to discretised material domains and subsequently integrates them through a partitioned approach and interface coupling method.The material points and the finite elements are utilized for the potential melting region and the non-melting region,respectively,such that their respective advantages in solving extreme deformation and small deformation problems are incorporated into the method for enhancing efficiency without compromising accuracy.Numerical cases demonstrate the accuracy of the proposed method for the thermo-fluid-solid coupling problems,its superior efficiency compared with existing algorithms,and the continuity of temperature and stress at the finite element-material point interface.This study presents an efficient method for the multi-physics coupling problems in metal additive manufacturing.