Estimating Temperature-Dependent Thermal Properties

Parameter estimation techniques are applied to estimate temperature-dependent thermal properties from a series of transient experiments. Several experiments with 1D and 2D heat flow that cover a range from room temperature to 500 C are analyzed. Temperature-dependent thermal properties are estimated by connecting the independent experiments in the series during the analysis. The techniques are applied to estimate effective properties of carbon-carbon composite. The temperature dependence of two components of thermal conductivity and volumetric heat capacity are estimated to characterize the assumed orthotropic material. The techniques can be equally applied to other homogenous materials. Combining experiments during the analysis is referred to as a sequential analysis, which uses the concepts of regularization and prior information. Regularization controls variations in the estimated parameters. Prior information carries information from a previous analysis into a subsequent analysis. The functional dependence of the properties estimated with a sequential analysis show excellent agreement with previous analyses that considered the experiments independently. (Author)