Numerical calibration of a Lorentz force flowmeter

Abstract

Numerical simulation of complex-shaped devices for contactless electromagnetic flow measurement in metallurgy is a challenge for computational magnetohydrodynamics. We report a series of numerical simulations which demonstrate for the first time that it is possible to predict the calibration constant of a generic Lorentz force flowmeter (LFF) with an uncertainty close to the requirements of real-life industrial applications. Our simulations involve both magnetostatic computations of a complex-shaped magnet system and magnetohydrodynamic computations of the flow of a liquid metal in a nozzle under the influence of a predominantly transverse magnetic field. In order to assess the role of turbulence, the simulations have been performed both for laminar and for turbulent flows using Reynolds-averaged Navier–Stokes equations in the latter case. In addition to the numerical simulations we have measured the calibration constant of the considered LFF using room-temperature liquid metal instead of liquid aluminum. A comparison between the numerically predicted and the measured values of the calibration constant shows that they differ by only 3.4%. This result suggests that numerical calibration of a LFF may become an economic alternative to expensive full-scale experimental calibration.