自然边界元与有限元的耦合及其应用

Coupling Method Between Natural Boundary Element and Finite Element and Its Application

为了提高计算速度和有效地减少计算量,基于无限平面弹性问题的自然边界元与普通有限元的耦合方法,提出了一种在工程分析软件ANSYS下的实现方式;详细介绍了耦合方法的理论依据及其在ANSYS下的具体实现步骤;用这种耦合方法研究了地下拱形巷道围岩应力的计算问题,并将耦合法计算结果与ANSYS软件计算所得到的结果进行对比分析.结果表明,耦合法计算稳定,计算结果准确可靠,在半径10 m的情况下使用耦合法计算的结果精度与在半径200 m的情况下单独使用ANSYS计算的结果精度相当;同时,耦合法较普通有限元算法收敛速度更快,计算量更小.

For the purpose of speeding up computing and reducing calculation amount,we propose a coupling method between natural boundary element and finite element for infinite plane elastic problem in ANSYS,describe the theoretical basis of the coupling method,and introduce the concrete steps in ANSYS.The problem about surrounding rock of tunnel is studied using the the coupling method.By comparing the results from different computational methods,the precision of results by using the coupling method when radius is 10 m is similar to the results by using ANSYS when radius is 200 m,showing that the results of coupling method are accurate and reliable.The analysis shows that the coupling method has a faster convergence and a smaller amount of calculation than finite element method.