pockets of relatively stagnant air (referred to as stall cells) which, rather than moving in the flow direction, rotate around the circumference of the compressor. In part-span stall, the flow separation only occurs at the outermost portions of the blades, while in full-span stall, the flow has separated along the entire length of the blade.

The stall cells rotate with the rotor blades, but slower than the rotor's speed; in part-span stall, the stall cells rotate at typically 50 to 70% of their speed, while in full-span stall, the stall