Magnetic circuit of electromagnetic flow meter with capacitive electrodes

This paper deals with analysis of magnetic circuit of electromagnetic flow meter with capacitive electrodes. There are several possibilities how to design magnetic circuit for creating preferably homogenous magnetic field with constant magnetic flux density. In the case of electromagnetic flow meter with capacitive electrodes, there is strong requirement to high level and homogeneity of magnetic flux density, because of very low level signal on the capacitive electrodes. One of possibilities how to create strong homogenous magnetic field is to use driving coil with ferrite magnetic circuit. There is analyzed shape and value of magnetic field flux density inside the pipe of designed magnetic circuit and simulated in ANSYS software in this paper. There are also compared characteristics of this design with ferrite circuit with characteristics of magnetic field with classical coils placed directly on the measuring pipe. Evaluated results from simulation software are compared with experimental measurement in final discussion.