Model-Based Cavity Shape Estimation in a Gas-Liquid System With Nonuniform Image Sampling

Abstract

A water model is studied to simulate physical phenomena in the Lintz-Donawitz steel converter. The depression in the liquid, due to the impinging gas jet, is measured by means of a video camera. Image processing tools are used to extract the edge of the surface indentation. The measured edge, sampled in a special way, is used together with a nonlinear mathematical model to obtain a description of the cavity profile. The parameters of the mathematical model are optimized to match the registered cavity edge in the image at a set of sampled points. Three ways of choosing sampling points for the optimization are proposed and compared on simulated as well as experimental data. An approach involving an observer decreases the computation time with an acceptable loss of accuracy of the estimates.