Three-Dimensional Effect of the Unsteady Vortex Lift Mechanism

An Immersed Boundary (IB) method is employed to simulate the rotor/stator interaction flow for a low-speed compressor working at different axial stage gaps in this paper. The flow variation due to the unsteady-vortex mechanism induced by reducing the stage gap is investigated and the results reveal that one origin of the performance enhancement at a smaller gap is found to be the loading enhancement of the upstream rotor. This variation results in a higher intra-stage static pressure, which reduces the inversed pressure gradient around the hub of the stator and further suppresses the flow separation at this region. Therefore, both the pressure rise and efficiency of the compressor are found to be higher. © 2024 Science Press. All rights reserved.