Is there analytical solutions for eigenvalue problem of Helmholtz equation with radiation boundary condition?

Consider the following problems: -Uxx - Uyy+k2U=0; ∂U/∂n - ikU=0, on boundary of [-1,1]x[-1,1]; where  ∂U/∂n means  outside normal derivativerespect to the boundary, and i=sqrt(-1). The question...

11 April 2016 3,451 2 View