The Influence of Forces Due to Electromagnetic Pick-Ups on the Performance of Small Turbine Flowmeters

An analysis is presented of the influence of forces due to an electromagnetic pick-up on the calibration of small turbine flowmeters. The analysis shows how the forces can produce high starting flows. A comparison between the theory and the experimental results of calibrating a meter both with and without the electromagnetic pick-up suggests that the dominant effect of the pick-up is to produce an additional resisting torque which is almost independent of the rotational speed of the meter.