Application of the time-inclined operator on the unsteady numerical simulation in centrifugal compressor

A numerical method for the calculation of unsteady stator/rotor interaction in turbomachinery stage of arbitrary pitch ratio using time-inclined operator is presented. It is developed on the basis of the program solving the three dimensional, viscous, steady flowfield in the centrifugal compressor. Dual time-stepping is adopted to realize the unsteady simulation; time-inclined operator is employed to transform the Navier-Stokes equations. It is realized without an approximation to a ratio of small integers or to scale geometry, the passages used for computation are minimum, and the computation time is also small. The results using time-inclined operator are also compared with the computation using NUMECA. It shows the program developed by the author can predict the flowfield in the centrifugal compressor accurately.