Analysis of extrapolation boundary conditions for the linearized Euler equations Original Research Article

The often-used practice of extrapolating all variables at a subsonic, outflow boundary is investigated. For steady state calculations, we show that the L2 error in a subdomain of fixed size decreases with the distance to the far field boundary. Thus, error reduction can be obtained by expanding the size of the computational domain. Numerical experiments using the Euler equations corroborate the theoretical prediction.