Abstract:

Effects of upstream and downstream stators on the unsteady flow in the rotor tip region in a low-speed two-stage axial compressor under high loading operating condition are investigated by numerical method. The result shows that double leakage vortexes are the dominating flow behaviors in the rotor tip region. Downstream rotor-stator interaction increases the unsteady fluctuating intensities of the rotor tip clearance flow and the tip leakage loss. Upstream stator-rotor interaction reduces the double leakage flow intensity in the rotor tip region. Comparing with that of no upstream and downstream stator interactions, the total pressure loss has a 9.1% decrease in the rotor tip region with concurrent upstream and downstream stator interactions. The improvement of the rotor tip performance mainly comes from the upstream unsteady stator-rotor interaction.

Key words: unsteady flow, tip leakage vortex, rotor-stator interaction, compressor