An adaptive finite element PML method for Helmholtz equations in periodic heterogeneous media

The paper concerns the numerical solution for the wave propagation problem in periodic heterogeneous media. The homogenization method is utilized for the solution in the bounded periodic structure with highly oscillating coefficients. The perfectly matched layer (PML) technique is adopted to truncate the unbounded physical domain into a bounded computational domain, and the exponential convergence of Cartesian PML is generalized to the Helmholtz transmission problem in periodic heterogeneous media. An efficient adaptive finite element algorithm based on reliable a posteriori error estimate is extended to solve the homogenized PML problem, and the reliability of the estimator is established. Numerical experiments are included to demonstrate the competitive behavior of the proposed method.