A simple Chimera grid method is developed for complex flows with moving boundaries. Based on the interpolation condition, a coupling strategy is proposed where algebraic equations are reconstructed to couple different domains. With respect to other methods, the coupling of different domains can be accomplished with the employment of any discretization scheme and the iterative process or the iterative solver are avoided. The process of reconstruction is simple to be implemented by the node-by-node replacement, which makes little change on the original code. In addition, the reconstructed system matrix keeps symmetric and positive definite, hence the old solver is appliable. The developed method has a clear physical meaning, namely the transmission condition of Dirichlet/Neumann type. The interpolation condition makes the variable continuous across the interior boundaries, which is the Dirichlet condition, while the Neumann condition is imposed by the reconstruction of the system matrix and the right hand side. For the flows with moving boundaries, this method cannot be applied directly as the interpolation condition varies. The corresponding change on reconstruction of the right hand side is conducted to resolve moving boundaries. Finally, the reliability and the accuracy of the present method are validated by several benchmark problems. The simulation results show that the accuracy of the discretization scheme is not affected by the present coupling strategies.

为具有移动边界的复杂流开发了一种简单的 Chimera 网格方法。基于插值条件，提出了一种耦合策略，其中重构代数方程以耦合不同的域。对于其他方法，不同域的耦合可以通过采用任何离散化方案来完成，并且避免了迭代过程或迭代求解器。重构过程简单，通过逐节点替换的方式实现，对原代码改动不大。此外，重构的系统矩阵保持对称和正定，因此旧的求解器是适用的。所发展的方法具有明确的物理意义，即Dirichlet/Neumann型的传输条件。插值条件使变量在内部边界上连续，这就是狄利克雷条件，而诺依曼条件是由系统矩阵和右手边的重构所施加的。对于边界移动的流，由于插值条件的变化，这种方法不能直接应用。对右手边的重构进行相应的改变以解决移动边界。最后，通过几个基准问题验证了本方法的可靠性和准确性。仿真结果表明，离散化方案的精度不受当前耦合策略的影响。对于边界移动的流，由于插值条件的变化，这种方法不能直接应用。对右手边的重构进行相应的改变以解决移动边界。最后，通过几个基准问题验证了本方法的可靠性和准确性。仿真结果表明，离散化方案的精度不受当前耦合策略的影响。对于边界移动的流，由于插值条件的变化，这种方法不能直接应用。对右手边的重构进行相应的改变以解决移动边界。最后，通过几个基准问题验证了本方法的可靠性和准确性。仿真结果表明，离散化方案的精度不受当前耦合策略的影响。