Continued developments in the modeling of complex dimensions and orientation variation in split D differential eddy current probes

Abstract

In this paper, model benchmarking for differential eddy current probes is presented, addressing increasing probe complexity including asymmetry, positional, and orientation variations. In prior work, results were presented showing that current models are capable of modeling, with a high degree of accuracy, the variations that come from dimensional, position, and orientation variations; however, one challenge concerned addressing some inherent irregularity and uncertainty in the dimensions of commercial eddy current probes. This current effort addresses these challenges using larger differential coil assembly with coil construction that is more precise and accurate, and through improved model construction and increased mesh resolution. A model validation study is presented that verifies the capability of modeling software to accurately represent probes with varying angle and for different probe designs. Results are also presented highlighting efforts to reduce modeling error observed in prior work in hopes of identifying a metric for how angular variation along the scan direction affects the probe response.