This paper provides an accurate, robust and efficient methodology for solving steady transonic turbomachinery flows. The Euler fluxes are discretized in space using a hybrid multidimensional upwind method, which, according to the local flow conditions, uses the most suitable Fluctuation Splitting (FS) scheme at each cell of the computational domain. The viscous terms are discretized using a standard Galerkin finite element scheme. The eddy viscosity is evaluated by means of the Spalart- Allmaras turbulence transport equation, which is discretized in space by means of a mixed FS-Galerkin approach. The equations are discretized in time using an implicit Euler scheme, the Jacobians being evaluated by two-point backward differences. The resulting large sparse linear systems are solved sequentially using a preconditioned GMRES strategy. The proposed methodology is employed to compute the 2D subsonic and transonic turbulent flows inside a high-turning turbine-rotor cascade, as well as a 3D subsonic turbulent flow inside the Stanitz elbow.
A GMRES fluctuation splitting method for steady viscous flows / Bonfiglioli, A.; De Palma, P.; Pascazio, G.; Napolitano, M.. - (2001). (Intervento presentato al convegno 15th AIAA Computational Fluid Dynamics Conference, Fluid Dynamics and Co-located Conferences tenutosi a Anaheim, CA nel 11-14 June 2001) [10.2514/6.2001-2624].
A GMRES fluctuation splitting method for steady viscous flows
De Palma, P.;Pascazio, G.;Napolitano, M.
2001-01-01
Abstract
This paper provides an accurate, robust and efficient methodology for solving steady transonic turbomachinery flows. The Euler fluxes are discretized in space using a hybrid multidimensional upwind method, which, according to the local flow conditions, uses the most suitable Fluctuation Splitting (FS) scheme at each cell of the computational domain. The viscous terms are discretized using a standard Galerkin finite element scheme. The eddy viscosity is evaluated by means of the Spalart- Allmaras turbulence transport equation, which is discretized in space by means of a mixed FS-Galerkin approach. The equations are discretized in time using an implicit Euler scheme, the Jacobians being evaluated by two-point backward differences. The resulting large sparse linear systems are solved sequentially using a preconditioned GMRES strategy. The proposed methodology is employed to compute the 2D subsonic and transonic turbulent flows inside a high-turning turbine-rotor cascade, as well as a 3D subsonic turbulent flow inside the Stanitz elbow.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.