Electromagnetic flowmeters in multiphase flows

摘要

The response of an Electromagnetic Flowmeter to a secondary, nonconductingphase in a continuous conducting phase is investigated. Experiments are carriedout on a commercial 2" Foxboro flowmeter with sinusoidal mains fieldexcitation and point electrodes. The main aspects which are looked for are thechange in flow signal and transformer signal. A mathematical model isdeveloped to simulate the effect of the nonconducting phase in. the form ofsingle spherical particles. The model also allows one to alter the electrodegeometry. A second flowmeter is designed to incorporate an improvedelectrode and coil geometry as well as a newly designed signal processing unit.In a series of experiments, the predictions of the theoretical model have beenmostly verified.