The influence of excitation coil size on the eddy electric field and on overcoming slurry noise in electromagnetic flowmeter

Abstract

Abstract When the electromagnetic flowmeter (EMF) measures the slurry flow, the sensor signal of EMF will be disturbed by the intense slurry noise. How to use the eddy electric field more effectively to overcome the slurry noise is a problem worthy of further investigation. In this paper, the influence of the size change of the excitation coil in the conventional sensor of EMF on the overcoming of slurry noise by the eddy electric field was researched. Firstly, the strength of the eddy electric field in different sizes of rectangles was discussed by using the rectangular excitation coil model. The result of the analysis was that the eddy electric field intensity increases with the increase in coil size. Finally, the effect of the size change of the excitation coil on the slurry flow signal was researched. The experimental results show that the effect of overcoming slurry noise becomes better as the size of the excitation coil increases.