Shaft Revolution - an overview | ScienceDirect Topics
During the rotation of the compressor shaft, at one shaft revolution, the number of working volumes of the main screw lobes z 1 contribute towards the process, so that the total mass participating is m z 1. Hence the actual fluid mass flow m ̇ [kg/s] is m ̇ = mz 1 n / 60 where n is the number of revolutions per minute of the main rotor.