EXIT FLOWFIELD OF AN EMBEDDED STATOR IN A MULTISTAGE AXIAL-FLOW COMPRESSOR

A complete area traverse downstream of the second stator of the Pennsy lvania State University Multistage Compressor Facility has been carrie d out at the peak efficiency and peak pressure ratio operating conditi ons using a miniature (1.07-mm-diam) five-hole probe and a thermocoupl e probe, Axial velocity, total pressure, and total temperature contour s are presented and discussed at both operating conditions, Blade-to-b lade profiles of total velocity and absolute flow angle presented at t hree representative radii show the effect of loading on the wake struc ture between the two operating conditions, The stator clearance flow a nd hub rotation result in flow underturning (from design), which persi sts up to 10% of the span from the hub, A region of low fluid momentum develops on the suction side of the stator blade endwall (casing regi on) corner at both operating conditions, The low fluid momentum region in the suction side casing endwall corner is identified as the domina nt source of now unsteadiness to the downstream rotor at both compress or operating conditions, This is seen in the distribution of apparent stresses, which are confined to the wake region along most of the span , with the exception of the low fluid momentum core in the endwall reg ion where significant levels are reached across a substantial portion of the passage at both operating conditions.