Effect of the tip clearance on the flow structure of rotating stall cell has been investigated experimentally in an axial flow compressor rotor. In the low-speed research compressor rotor tested, the number of multiple stall cells with short length-scale and the rotating speed change with the tip clearance. For two different tip clearances, the flow structure of rotating stall cell was analyzed by measuring the pressure distribution on the casing wall and the velocity distributions upstream and downstream of the rotor, using 'Synchronous Field Measurement' and 'Double Phase-Locked Averaging Technique'.
