Wake behavior downstream of a transonic compressor rotor

Abstract

Measurements of the static pressure resolved in radial and axial directions downstream of a transonic compressor rotor have been harmonically analyzed. The investigation is part of a program addressing the behavior of disturbances in strongly swirling flows. There is evidence that the wakes are radially outward and carry static pressure disturbances with them. The harmonic analysis of the static pressure measured at the tip radius indicates a shift toward higher frequency of the peak in the power spectrum as the flow proceeds downstream. It is suggested that this increasing frequency associated with the power peak results from the wakes being convected downstream in a fluid which has increasing swirl velocity as it travels away from the rotor.