Characteristics of the Near Wake of a Compressor of a Fan Rotor Blade

Research reported in this paper covers an experimental investigation of the rotor wake. The experimental investigation included a study of the mean velocity, turbulence intensity, and Reynolds stress variations across the wake of a lightly loaded rotor blade at various axial and radial locations. Only the mean velocity data and their interpretation are presented in this paper. Measurements were carried out with a triaxial probe, rotating with the rotor and stationary behind the rotor. Also, measurements were made with a spherical head static pressure probe rotating with the rotor. Wakes were measured at various incidences to discern the effect of blade loading on the rotor wake. The wake is found to be three-dimensional in nature with appreciable radial velocity. The measurements close to the blade trailing edge indicate that the decay of the wake is rapid in this region. The wake data are correlated to derive expressions for the profile and decay of all the components.