Measurement of the spatio-temporal distribution of harmonic and transient eddy currents in a liquid metal

TL;DR

This paper presents a method to measure and analyze the spatio-temporal distribution of harmonic and transient eddy currents in liquid metals, validating analytical and numerical models for complex geometries.

Contribution

It introduces a measurement technique using voltage drops in a potential probe and compares results with analytical and numerical models, including non-conducting objects.

Findings

Measured eddy current distributions match analytical expressions for a conducting half-space.

Deformation of eddy currents due to a non-conducting torus is successfully measured and compared with numerical results.

The method can be extended to arbitrary geometries for non-destructive testing applications.

Abstract

Harmonic and transient eddy currents in a liquid metal positioned above an excitation coil are determined by measuring the voltage drop in a simple potential probe. The resulting spatio-temporal eddy current field is compared with the corresponding analytical expressions for a conducting half-space. Further, a deformation of the eddy current distribution due to a non-conducting torus immersed into the liquid metal is measured and compared with numerical results. The method can be generalized to arbitrary geometries, and might help to validate numerical models for non-destructive testing and magnetic inductance tomography.