Inverse method for simultaneously estimating multi-parameters of heat flux and of temperature-dependent thermal conductivities inside melting furnaces

Abstract

The purpose of this study is to predict the time-varying protective bank that coats the internal surface of the refractory brick walls of a melting furnace. An inverse heat transfer procedure is presented for predicting simultaneously operating and thermal parameters of a melting furnace. These parameters are the external heat transfer coefficient, the thermal conductivity of the phase change material (PCM) and the time-varying heat load of the furnace. Once these parameters are estimated, the time-varying protective PCM bank can be predicted. The melting and solidification of the PCM is modeled with the enthalpy method. The inverse problem is handled with the Levenberg-Marquardt Method (LMM) combined to the Broyden method (BM). The models are validated and the effect of the position of the temperature sensor embedded in the furnace wall, of the data capture frequency and of the measurement noise, is investigated. A statistical analysis for the parameter estimation is also carried out. Analysis of the results yielded recommendations concerning the location of the embedded sensor and the data capture frequency.