Fast Direct Solution of the Helmholtz Equation with a Perfectly Matched Layer/an Absorbing Boundary Condition
نویسندگان
چکیده
We consider efficient numerical solution of the Helmholtz equation in a rectangular domain with a perfectly matched layer (PML) or an absorbing boundary condition. Standard bilinear (trilinear) finite element discretization on an orthogonal mesh leads to a separable system of linear equations for which we describe a cyclic reduction type fast direct solver. We present numerical studies to estimate the reflection of waves by an absorbing boundary and a PML, and we optimize certain parameters of the layer to minimize the reflection.
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تاریخ انتشار 2002