Numerical analysis of the 3D swirling flow in centrifugal compressor volutes

The improvement of centrifugal compressor performance and the control of the radial forces acting on the impeller due to the circumferential variation of the static pressure caused by the volute require a good understanding of the flow mechanisms and an accurate prediction of the pattern inside the volute. A 3D volute calculation method has been developed for this purpose. The volume is discretized by means of hexahedral elements. A cell vertex finite volume approach is used in combination with a time marching procedure. The numerical procedure makes use of a central space discretization and four step Runge-Kutta time stepping scheme. The artificial dissipation used in the solver is based on the fourth order differences of the conservative variables.