摘要
The immersed boundary method is well-known,popular,and has had vast areas of applications due to its simplicity and robustness even though it is only first order accurate near the interface.In this paper,an immersed boundary-augmented method has been developed for linear elliptic boundary value problems on arbitrary domains(exterior or interior)with a Dirichlet boundary condition.The new method inherits the simplicity,robustness,and first order convergence of the IB method but also provides asymptotic first order convergence of partial derivatives.Numerical examples are provided to confirm the analysis.