Experiments with approximate radiation boundary conditions for computational aeroacoustics Original Research Article

We present a series of numerical experiments on the accuracy of approximate radiation boundary conditions for computational aeroacoustics based on Padé approximants. Our test problem is described by an infinite periodic array of pressure pulses, for which we can independently evaluate the exact solution by numerical quadrature. It is demonstrated that acceptable long time accuracy can be achieved, but only if conditions of high order are employed. As predicted by theory, the order required for a given accuracy is proportional to the time of the simulation.