Determination of thermal properties in multilayer materials

GUILLERMO FEDERICO UMBRICHT; DIANA RUBIO; DOMINGO ALBERTO TARZIA

Cancún

Congreso; XXX International Materials Research Congress (IMRC); 2022

The objective of the work is to identify unknown materials composing a multilayered bar with solidsolidinterfaces. The thermal conductivity of each layer is determined based on simulated noisy dataa stationary heat transfer process in a material that is assumed to be fully insulated on its lateralsurface. A constant temperature is imposed at the left edge while heat dissipation by convection, isassumed at the other end. Assuming that the layers are perfectly assembly, the temperature on thebar is a piecewise polynomial that depends on the parameters of the layers (depth, thermalconductivity), the temperature at the edges and the room temperature. Under this assumption, thethermal conductivity values of the layer materials are obtained based on the available data. In realcases the layer interfaces present thermal resistance, or other anomalies, that can modify thematerial properties. The approach given here allows calculating the thermal conductivitiescorresponding to the behavior of the material. Hence, they will not be exactly that of the materialof each layer, but rather it will be modified according to the anomalies that occur at theinterfaces. In the case where all thermal properties of the multilayer material are known, theproposed estimation helps to quantify how imperfections in the interfaces affect these values.Numerical results are included and sensitivity and elasticity analyses are also perform to measurethe accuracy of the mathematical estimates based on data errors.