We discuss measuring error caused by fabrication and measurement of a T-Type nano sensor with suspended sub-micrometer Pt hotfilm heater which have been developed to measure thermal property of individual nanowire materials. Comparing numerical simulation and 1-dimenshional analysis, it is appeared that thermal conductivity of nanowire material such as carbon nanotube is calculatied 17% lower. As example, thermal conductivity measuring result of SiC nanowire is reported and error caused by contact thermal resistance is depend on the contact length and it becomes as much as 20% sometimes. It can be said that future measuring has higher reliability by these error estimation.
A thermal microscope is a useful tool for investigating the spatial distribution of the thermal transport properties of materials. However, for materials with relatively high thermal effusivities, it is well known that the values calculated on the basis of the conventional one-dimensional heat flow solution are higher than the values provided in the literature. In this study, we developed a simple calibration procedure for a thermal microscope to measure the thermal effusivities of materials by using several reference materials whose thermal effusivities are known. It is expected that the temperature response will be influenced by not only the thermal effusivity but also the heat capacity per unit volume. However, reference samples with different heat capacities per unit volume were used. In comparison with the calculated values obtained with the conventional one-dimensional heat flow solution, the values for pure iron obtained with our calibration procedure, without considering the heat capacity per unit volume, were closer to the values provided in the literature. We found that this procedure is useful for calibrating a thermal microscope easily for measuring thermal effusivity.
The application of thermal microscope to the measurement of local thermal properties has drawn considerable scientific interest. We report the application of a thermal microscope to the measurement of thermal effusivity for films comprising alumina deposited on a substrate, which were fabricated by an electrophoretic deposition method. The measured data was analyzed to consider the undulations on the sample surface. For these samples, it is expected that unsteady heat flow conditions will affect the measurements. The thermal effusivity of these samples was about 1×10³ Js-0.5m-2K-1; this value is smaller than that for dense alumina because an alumina grain make contact with a point.
On a food heating process, the Joule heating system has been received keen attentions as a sophisticated heating system because of accurate heating, non-scorching and cleanness. In a previous paper, we developed the visualizing method to observe and record the internal temperature profile as a picture in a food material and compared the visualized results with the data which simulated by a numerical analysis. However, a combined material exists in the container generally. In this paper, the measurement of potential distribution and numerical analysis are proposed and heat generation for the combined material is clarified.