Experimental investigation of blade-tip leakage flow control in a low-speed axial compressor using natural aspiration through casing wall slot
Year: 2026
Type: article
Abstract: Mitigating rotor blade tip leakage flow in axial compressors is crucial for improving aerodynamic performance and extending the stable operating range. This study experimentally evaluates natural aspiration through a circumferential casing slot upstream of an isolated rotor blade row, with the configuration informed by previous numerical studies. The treatment passively admits ambient air without an external compressed-air supply. Experiments at 1600 rpm compared plain and treated casings using performance measurements, casing-wall static pressures, and single-wire hot-wire anemometry. Fourier-based spectral analysis was used to examine the measured flow unsteadiness. The performance curves indicated an approximately 1.2% increase in the pressure-rise coefficient. The reported operating points extended to an inlet-flow coefficient of 0.28 for the treated casing and 0.32 for the plain casing. Wall-pressure distributions and velocity spectra provided complementary information on the near-tip flow response, without independently establishing vortex weakening or a specific stall-inception mechanism. The admitted mass flow and overall efficiency were not quantified, limiting conclusions about rotor-throughflow-based stability improvement and efficiency. The results provide an experimental basis for evaluating passive air admission as a compressor casing treatment.
Source: Scientific Reports
Institution: Iran University of Science and Technology
Language: English
Subfield: Aerospace Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,690
OpenAlex ID: W7225456759