Three-dimensional turbulent flow field of axial compressor rotor passage

The 3-D turbulent flow at the exit of a single-stage axial compressor rotor passage was measured using both a hot-wire probe and a high frequency pressure probe, while the 3-D mean flow in the tip region of an isolated axial compressor rotor passage were surveyed using a conical five-hole pressure probe with the help of a rotating four-axis probe traverse mechanism on a low-speed large-scale axial compressor rig. The development of the tip leakage vortex and its mixing with the end-wall boundary layer are decisive for the flow characteristics in design condition. With the mass flow reducing, the blade boundary layer on the suction surface is getting thicker and even separates in near stall condition, while the radial migration of the blade boundary layer becomes stronger. A strong vortex forms at the casing-blade suction surface corner, and part of low-energy fluid is transported to the mid-passage, mixing with the thickened end-wall boundary layer, the tip leakage vortex, the blade scrape vortex and the main flow.