An Electromagnetic Flowmeter with Plural Pairs of Electrodes

Abstract

In order to reduce the flow profile effects on the electromagnetic flowmeters, this paper proposes an electromagnetic flowmeter with plural pairs of electrodes.
In case of a uniform magnetic field the optimum configuration for two pairs of electrodes has been determined to be the position 20deg. shifted from the conventional electrode axis. Numerical simulations for which the flow profile downstream of 90° bend has been applied, flow tests using the eccentric orifices have proved that two pair electrodes type is able to reduce the errors due to the non-axisymmetrical flow profile.
It has been also shown that the combined configuration of two pair electrodes and non-uniform magnetic field proved to make the required length downstream of bends and valves shorter than single pair electrodes.