The aim of the present paper is the investigation of the influence of non-reflecting boundary conditions on the calculation of the three-dimensional inviscid steady rotational flow inside a high pressure ratio centrifugal impeller.
The space discretization of the Euler equations was done using the finite volume technique and the multistep Runge-Kutta scheme was used for the time integration. Nonreflecting boundary conditions using Fourier decomposition are applied at inflow and outflow boundaries.
Computations show that convergence to steady state is reached faster when non-reflecting boundary conditions are used compared to the reflecting boundary conditions. Studying the influence of the non-reflecting boundary conditions on the accuracy of the flowfield prediction, it is concluded that the location of the upstream boundary has a negligible influence on the solution even in the case where a shock is crossing the boundary.