Characteristics methods for transient analysis of wave propagation in unbounded media Original Research Article

A method based on characteristics was developed recently for the analysis of wave propagation in unbounded layered media [7]. In this paper, the method is extended to problems involving spherical and cylindrical computational boundaries. The procedure resulting from straightforward extension of the method meets with several difficulties in stability and accuracy. Modifications based on radial scaling and upwinding are applied to circumvent these difficulties. The resulting boundary conditions have all the properties desired in an artificial boundary condition. Numerical experiments are presented to illustrate the effectiveness of the procedure.