Iterative radiation boundary conditions for finite element solutions of the scalar wave equation

New families of radiation boundary operators are proposed for finite element simulations of wave propagation problems characterized by the scalar wave equation. These operators have the form Bu(j+1) = Cu-(j), j = 1, 2,..., J, where B is the Dirichlet, Neumann, or the Robin operator, and G is an appropriately chosen local operator. Since B is a standard operator compatible with the wave equation, and C acts on the known iterate u((j)), the radiation operators can be easily incorporated into a typical finite element code. The proposed approaches are shown to produce very good results for the test cases considered. (C) 2001 Elsevier Science B.V. All rights reserved.