Application of a single step temporal imaging of magnetic induction tomography for metal flow visualisation

Magnetic induction tomography (MIT) is a new technique to image the electromagnetic properties of an object by mutual induction data of pairs of excitation and sensing coils. MIT has potential in visualisation of metal flow for continuous casting, mainly because of its potential to deliver images with high temporal resolution. A dynamic magnetic induction imaging technique is developed with the aid of a novel direct temporal imaging method. This paper proposes a new approach, which directly accounts for correlations between images in successive data frames. The forward problem in MIT is a general eddy current problem and is solved by an edge finite element method. The inverse problem is treated as a dynamic inverse problem, and the conductivity distribution is estimated with the aid of the direct temporal imaging method. Experimental tests illustrate the performances in the sense of spatio-temporal resolution using the real metal flow in continuous casting. Results are compared with reconstruction algorithms based on independent frames.