Eddy current sensor array processing

This paper presents a technique, based on the concept of eddy current, for imaging the extent of solidification of molten metal flowing in a pipe. We derive a mathematical model which relates the distribution of solidification to external measurements collected by a virtual array of sensors (solenoid) around the pipe. The distribution is approximated by a set of unknown parameters. The model is described by integral equations which are solved numerically using the moments method. An iterative algorithm is developed to estimate unknown parameters and hence determine the shape and the thickness of metal solidification. Results from simulations show that the iterative procedure converges very fast