The bulk thermal conductivity is analyzed by the Finite Element Method (FEM) for the two phase material which consists of one dispersed phase and the other continuous phase. The effects of the spatial distributions and the shapes of the dispersed phase on the bulk thermal conductivity are quantitatively evaluated. The analyzed results reveal the parametric relationship of the bulk thermal conductivity with the configurations, volume fractions and thermal conductivity ratios of the dispersed phase, and indicate the applicable range of the Schulz calculation model on this subject.

View full abstract

Very few data on the specific heat capacity of thermocouple materials over a wide temperature range exist. We measured the specific heat capacities at constant pressure of chromel® and alumel® of K-type thermocouples with a power-compensated differential scanning calorimeter in the temperature range 304K-574K. First, we measured the specific heat capacity of synthetic sapphire as a standard reference material to determine the optimum heating rate. Next, we measured the specific heat capacity of high-purity copper as a standard reference material to determine the optimum heat capacity ratio of the specimen and an aluminium pan and to estimate the measurement accuracy of the present calorimeter. Lastly, we measured the specific heat capacities of chromel® and alumel® using the optimum heating rate and the optimum heat capacity ratio. The measured specific heat capacity was compared with the existing published data. The Curie temperature of alumel and the applicability of the Kopp-Neumann law for the measured specific heat capacity were also discussed.

View full abstract