Transient eddy current flow metering

TL;DR

This paper introduces a calibration-free method for measuring flow velocities in liquid metals and semiconductor melts using transient eddy currents induced by pulsed magnetic fields, validated through experiments with aluminum and liquid GaInSn.

Contribution

It presents a novel variant of eddy current flow measurement that is calibration-free and applicable to industrial liquid metal flows.

Findings

Validated with aluminum spinning disk

Initial tests with liquid GaInSn show promising results

Method effectively measures flow velocities without calibration

Abstract

Measuring local velocities or entire flow rates in liquid metals or semiconductor melts is a notorious problem in many industrial applications, including metal casting and silicon crystal growth. We present a new variant of an old technique which relies on the continuous tracking of a flow-advected transient eddy current that is induced by a pulsed external magnetic field. This calibration-free method is validated by applying it to the velocity of a spinning disk made of aluminum. First tests at a rig with a flow of liquid GaInSn are also presented.