Mathematical investigation of the flow profile sensitivity of the electromagnetic velocimeter for metallurgical fluid-flow measurements

Abstract

Velocity measurements probably represent the greatest challenge to the experimentalist or physical modeler because of the multidimensional, unsteady nature of many flows encountered in process metallurgy. The principle of electromagnetic velocity measurement has been widely used in metallurgical process industries for flow measurements. The effect of flow or velocity profile on the sensitivity of the electromagnetic flow meter has been investigated using analytical methods. The solution of electromagnetic flow meterequation del2phi = div(V over arrow pointing right x B over arrow pointing right) can be expressed as an integral containing the Green's function. From the integral solution it is shown precisely how the output signal of the electromagnetic flow meter depends on the velocity profile of the fluid. It is observed that practically it is not possible to eliminate the velocity profile dependence. It is concluded that elimination of flow profile dependence on the sensitivity of the flow meter cannot be completely achieved even with the shaping of the magnetic field.