Estimation of Thermodynamic and Transport Properties of Metallic Materials

A three-layer apparatus for thermal property measurements (thermal conductivity k and volumetric heat capacity C) of high-conductivity materials where a thin electrical heater is sandwiched between two identical samples is investigated. In particular, the thin heater is modeled as a lumped body so that the heat conduction transient problem concerns a one-dimensional (1-D) finite single-layer rectangular body (sample) subject to a boundary condition of the fourth or sixth kind at the heated surface and insulated at the backside. Specifi-cally, a boundary condition of the fourth kind accounts for the heater heat ca-pacity, while the one of the sixth kind considers also the imperfect contact be-tween heater and sample. Once the thermal field within the sample is known and the sensitivity coefficients are computed, an optimal experiment is designed by applying the D-optimum criterion in order to estimate accurately and simul-taneously k and C. Then the standard deviations of the estimates are also com-puted.