Optimal Heating Method for Simultaneous Estimation of Thermal Conductivity and Diffusivity in Transient Hot-Strip Method

Abstract

This article presents an investigation on transient hot-strip (THS) method for simultaneous estimation of thermal conductivity ( $k$ ) and diffusivity ( $\alpha $ ) based on an inverse parameter estimation technique. Four different heating configurations, such as constant, power law, exponential, and periodic heating, are considered for energizing the THS. In each case, the sensitivity of $k$ and $\alpha $ is analyzed with regard to its magnitude and existence of correlations between $k$ and $\alpha $ . Based on the aforesaid criteria, it was found that periodic heating is the best heating configuration for simultaneous estimation of unknown $k$ and $\alpha $ . Then optimum variables of the best heating configuration were found out based on the D-optimal test. Furthermore, numerical estimations were carried out using pseudoexperimental data to study the applicability of this method for estimation of unknown properties for a wider range of materials. The estimation results of this study reveal that this method is more suited for materials with low-to-medium range thermal conductivity.