Effects of stator tip bifurcation on flow field structure and performance of a transonic compressor

Abstract This research introduces a novel structure, tip bifurcation, for compressor stators. Numerical simulations are conducted to explore how the stator tip bifurcation structure affects compressor performance and flow field structure under diverse operating conditions. All the findings indicate that the structure potently shifts the initial point of flow separation downstream and curtails the convergence of low-energy fluid around the suction corner under near-stall conditions. This adjustment further reduces the extent of corner separation in both the pitchwise and spanwise directions. As a result, this modification enhances the airflow capacity within the compressor passage, minimizes flow losses, and improves overall performance. However, it slightly decreases the peak efficiency by 0.23% and the stability margin of the compressor by 11%. The tip bifurcation enhances compressor efficiency and pressure ratio under near-stall conditions. A 4.7% increase in efficiency is observed at 169.4 kPa, corresponding to the stall point of ORI, which is adopted as the reference near-stall condition for comparison.