Effects of Tip Leakage Flow on the Aerodynamic Performance and Stability of an Axial-Flow Transonic Compressor Stage

Abstract

To explain the effect of tip leakage flow on the performance of an axial-flow transonic compressor, the compressors with different rotor tip clearances were studied numerically. The results show that as the rotor tip clearance increases, the leakage flow intensity is increased, the shock wave position is moved backward, and the interaction between the tip leakage vortex and shock wave is intensified, while that between the boundary layer and shock wave is weakened. Most of all, the stall mechanisms of the compressors with varying rotor tip clearances are different. The clearance leakage flow is the main cause of the rotating stall under large rotor tip clearance. However, the stall form for the compressor with half of the designed tip clearance is caused by the joint action of the rotor tip stall caused by the leakage flow spillage at the blade leading edge and the whole blade span stall caused by the separation of the boundary layer of the rotor and the stator passage. Within the investigated varied range, when the rotor tip clearance size is half of the design, the compressor performance is improved best, and the peak efficiency and stall margin are increased by 0.2% and 3.5%, respectively.

Numerical investigation on the influence of nonuniform tip clearance on rotor tip-clearance flow field structure

“…20 ; the vortex structures are displayed in color with dimensionless helicity. The Q criterion [ 35 ] is defined to capture the vortex edge; the Q criterion and dimensionless helicity [ 31 ] are defined as follows (Eq. (6) and Eq.…”

“…8 displays the tangential velocity distribution in the section near the 33 %, 55 %, and 72 % chord lengths of the rotor under the peak efficiency conditions. The experimental data were measured by the laser Doppler velocimeter discussed in literature [ [31] , [32] , [33] ]. The comparison revealed that the shock wave positions obtained from the experiments and numerical calculations were consistent and the main TLF, and the shock location before and after the shock were accurately predicted.…”

Numerical Investigation of Unsteady Rotor–Stator Interaction Mechanism and Wake Transportation Characteristics in a Compressor with Non-Uniform Tip Clearance Rotor

“…The paper conducts a numerical investigation on the rotor blades using NASA Stage 35 [26][27][28] as the research subject. NASA Stage 35 consists of 36 rotor blades and 46 stator blades.…”