Apparent thermal conductivity measurement of anisotropic insulating materials at high temperature by the parallel hot-wire method

Influence of Radiation Heat Transfer on Parallel Hot-Wire Thermal Conductivity Measurements of Semi-Transparent Materials at High Temperature

“…The curves are in very good agreement and estimates made from the curves simulated with COMSOL Multiphysics ® using the ISO 8894-2:2007 method [2] lead to values of λ that differ by less than 0.5 % from the nominal value as shown in fig. 5b.…”

“…5b. The ISO 8894-2:2007 method [2] was detailed in a previous paper [1], it recommends the estimation for values of the ratio T (2t)/T (t) between 1.5 and 2.4, in the presented case the validity limit of the semi-infinite medium assumption reduces this interval to [1.7, 2.4]. The results obtained in the case where the extinction coefficient is very large are similar.…”

“…As previously pointed out in [1], knowledge of the thermal conductivity of high temperature insulating materials is of great importance for the control of industrial processes. It has also been stated that the parallel hot-wire method is one of the most suited method to measure the thermal conductivity at high temperature [1,2], moreover it is a standardized method [3]. Some recent developments in the modelling of this method have led to a better accuracy of the measurement [1,3].…”

“…Some recent developments in the modelling of this method have led to a better accuracy of the measurement [1,3]. Nevertheless, the estimation process is more often based on a purely conductive model, considering an equivalent thermal conductivity that is the sum of the thermal conductivity and of the radial conductivity [1,2,3,4,5,6]. This approximation holds true for optically thick media.…”

Thermal Conductivity Measurement of Flexible Composite Phase-Change Materials Based on the Steady-State Method

“…Xiao et al [ 20 ] found that the uncertainty of thermal conductivity measured by the laser flash method can be as large as 40% when the TCR on both sides of the measured sample is ignored by numerical investigations. Additionally, these methods are not suitable for measuring the thermal diffusivity of thermal insulation materials [ 21 ].…”