TOWARD PERFECTLY ABSORBING BOUNDARY CONDITIONS FOR EULER EQUATIONS

摘要

We examine the effectiveness of absorbing layers as nonreflecting computational boundaries for the Euler equations. The absorbing-layer equations are simply obtained by splitting the governing equations in the coordinate directions and introducing absorption coefficients in each split equation. This methodology is similar to that used by Berenger for the numerical solutiona of Maxwell's equations. Specifically, we apply this methodology to three physical problems--shock-vortex interactions, a plane free shear flow, and an axisymmetric jet--with emphasis on acoustic wave propagation. Our numerical results indicate that the use of absorbing layers efectively minimizes numerical reflection in all three problems considered.