Three-dimensional flows in a transonic compressor rotor

This study involved an experimental and numerical investigation of the three-dimensional flow occurring in a transonic compressor rotor. A better understanding of the flow physics in a transonic rotor is needed for advanced design purposes. This research involved experimental measurements on Compressor Stage "67", which is a NASA designed stage, along with the use of computational fluid dynamics (CFD) analysis.;A variety of data which could be used in a complementary fashion to improve the understanding of the flow physics was acquired. Detailed radial survey data which consisted of total pressure, static pressure, total temperature, and flow angle were obtained at stations upstream and downstream of the rotor blade row. Detailed velocity and turbulence profiles were obtained upstream of the rotor and were used as boundary conditions for the CFD analysis. Calibrated flush-mounted hot film probes were used to measure wall shear stress on the hub and casing wall upstream of the rotor and on the casing wall downstream of the rotor. The blade-to-blade shear stress angle distributions were obtained at four axial locations on the rotor casing using flush-mounted hot film probes.;A computational fluid dynamics analysis was conducted using a three-dimensional Navier-Stokes computer code. Results from the CFD analysis were compared with the experimental measurements, and aided in the physical interpretation of the experimental results. The comparisons illustrated the following flow physics: a rapid increase in the axial distribution of static pressure over the tip of a transonic rotor is indicative of the location of the passage shock within the rotor blade in the vicinity of the rotor tip; the wall shear stress on the tip casing at the rotor inlet is insensitive to flow but increased 30% at stall conditions; the wall shear stress on the tip casing at the rotor exit showed an increase of 175% (above peak efficiency) at stall conditions; and the blade-to-blade variations of the magnitude of the shear stress over the rotor tips is relatively small but the angle variation is very large. Future turbomachinery research is needed for development of design correlations.