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The electromagnetic flowmeter operates based on Faraday’s law of electromagnetic induction. When a conductor moves in a magnetic field and cuts through the magnetic field lines, an induced electromotive force e is generated at both ends of the conductor. The direction of this force is determined by the right-hand rule, while its magnitude is proportional to the magnetic field strength B, the length L of the conductor within the magnetic field, and the speed u at which the conductor moves. If B, L, and u are mutually perpendicular, then e = Blu. Similarly, in a uniform magnetic field with strength B, if a non-magnetic pipe with inner diameter D is placed perpendicular to the direction of the magnetic field, and a conductive fluid flows through this pipe at a speed u, the conductive fluid will cut through the magnetic field lines. By placing a pair of electrodes at the ends of a diameter in the pipe that is perpendicular to the magnetic field, it can be shown that as long as the flow velocity within the pipe is axially symmetric, an induced electromotive force will also be generated between the two electrodes: e = BD, where this value represents the average flow velocity across the pipe’s cross-section. From this, the volumetric flow rate can be calculated as qv = πDU. As can be seen from this equation, the volumetric flow rate qv is linearly related to the induced electromotive force e and the inner diameter D of the pipe; it is proportional to the magnetic field strength B, and it is independent of other physical parameters. This is the principle behind how an electromagnetic flowmeter functions. It should be noted that for this equation to hold true, certain assumptions must be met regarding the measurement conditions: ① The magnetic field must be a uniformly distributed and constant magnetic field； ②Axially symmetric diffusion of the flow velocity of the fluid under test ； ③The liquid being tested is non-magnetic ； ④The conductivity of the liquid being tested is uniform yet anisotropic. For more information, please visit the company’s official website at http://www.yb1518.com/. Please retain this link when reproducing the content! http://www.yb1518.com/UploadFiles/2012717174126829.jpg