NAVIER-STOKES SOLUTION OF TRANSONIC CASCADE FLOWS USING NONPERIODIC C-TYPE GRIDS

A new kind of C-type grid is proposed for turbomachinery flow calculations. This grid is nonperiodic on the wake and results in minimum skewness for cascades with high turning and large camber. The Reynolds-averaged Navier-Stokes equations are discretized on this type of grid using a finite volume approach. The Baldwin-Lomax eddy-viscosity model is used for turbulence closure. Jameson's explicit Runge-Kutta scheme is adopted for the integration in time, and computational efficiency is achieved through accelerating strategies such as multigriding and residual smoothing. A detailed numerical study has been carried out for a turbine rotor and for a vane. A grid dependence analysis is presented and the effect of the artificial dissipation is also investigated. Comparison of calculations with experiments clearly demonstrate the advantage of the proposed grid.