遷音速多段軸流圧縮機における非定常流れ場の大規模DES解析

抄録

The goal of this study is to elucidate complicated unsteady internal flow phenomena and their effects on aerodynamic characteristics in a transonic multi-stage axial compressor. The transonic flow field in the compressor, in which subsonic and supersonic regions coexist, takes on a knotty flow field. In the transonic axial compressor, the significance of highly accurate numerical analysis increases, because the experimental approach has some difficulties in measuring detailed internal flow. In this study, large-scale detached eddy simulations (DES) were conducted for the 2 stage transonic axial compressor on the K computer. The flow field at the design point was analyzed by data mining techniques to extract important fluid dynamic phenomena. The data mining techniques deal with vortex structures that are identified by the critical point theory and limiting streamlines that are visualized by the line integral convolution (LIC) method. This paper presents a comparison of full-annulus DES result and single passage RANS result, and describes unsteady effects of the bladerow interaction in the compressor.