遷音速多段軸流圧縮機の静翼列におけるハブ・コーナーはく離の抑制

抄録

The final goal of this study is to suppress hub-corner separation in a first stator cascade of a transonic 2-stage axial compressor. This study used an inverse design method based on meridional viscous flow analysis for designing first stator vane, and used large-scale detached eddy simulation (DES) in order to evaluate the flow field and the performance of the full stage of this axial compressor. The flow field in this compressor was analyzed by data mining techniques, which include a vortex identification based on the critical point theory and limiting streamlines visualized by the line integral convolution (LIC) method. In this study, chordwise blade loading distribution was modified to shift the peak load position from the front part to mid-chord, and give gently-sloping distribution profile at each span in order to suppress the hub-corner separation. As a result of modifying the chordwise blade loading distribution and redesigning the first stator vane, the hub-corner separation has been suppressed and the flow field in a first stator cascade has been also improved. For these reasons, total pressure loss coefficient in first stator has been decreased and the performance of full stage of the redesigned compressor has been enhanced by 0.53% in adiabatic efficiency compared with that of the original compressor. This paper describes how to suppress hub-corner separation and shows the flow field in a stator cascade in details.