The hot-disk method is a transient method for the measurement of thermal properties. This method can measure both the thermal conductivity and thermal diffusivity in a short time for isotropic materials. To establish a method for measuring the thermal properties of wood by the hot-disk method, the relationship between the thermal properties of wood obtained by the hot-disk method and those obtained by the steady-state method was investigated. The thermal properties were measured by the hot-disk method using small pieces of kiri (Paulownia tomentosa), sugi (Cryptomeria japonica), hinoki (Chamaecyparis obtusa), yachidamo (Fraxinus mandshurica), and buna (Fagus crenata) when the hot-disk sensor was in contact with the cross section, radial section, and tangential section. The thermal conductivities in the longitudinal, radial, and tangential directions were also measured by the comparison method using the same specimen. The thermal properties obtained by the hot-disk method and the steady-state method were compared, based on the assumption that the thermal diffusivity measured by the hot-disk method was the geometric mean of that in the two main directions in the plane of the sensor, and the thermal conductivity measured by the hot-disk method was a power of that in three main directions. As a result, the thermal conductivity obtained by the hot-disk method was 10–20% higher than that obtained by the steady-state method; the thermal diffusivity measured by the hot-disk method was equal to that obtained by the steady-state method on average, while in the former thermal diffusivity varied widely. These results were found to be explainable in terms of the Dufour effect, which is the heat flow induced by the mass flow caused by the heating of the sensor, and the existing findings on the time dependence of the sensitivity coefficient in the hot-disk method. The present study proposed two methods for calculating the thermal properties of wood from the hot-disk method were proposed, and it was found that the errors between the obtained thermal properties and those obtained by the steady-state method differed depending on the calculation method.

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通过热盘法测量的木材的热性能：与通过稳态法测量的热性能的比较

热盘法是一种用于测量热性能的瞬态方法。该方法可以在短时间内测量各向同性材料的热导率和热扩散率。为了建立一种通过热盘法测量木材热性能的方法，研究了通过热盘法获得的木材的热性能与通过稳态法获得的木材的热性能之间的关系。热性能通过热盘法测量，当热盘使用时，使用小块的kiri（泡桐），sugi（柳杉），hinoki（Chamaecyparis obtusa），yachidamo（Fraxinus mandshurica）和buna（Fagus crenata）。传感器与横截面，径向部分和切线部分接触。纵向，径向，垂直方向的热导率 切线方向和切线方向也使用相同的试样通过比较方法进行测量。基于以下假设，比较了通过热盘法和稳态法获得的热特性：热盘法测得的热扩散率是在平面内两个主要方向上的热扩散率的几何平均值。传感器，并且通过热盘法测量的热导率是三个主要方向上的功率的乘方。结果，通过热盘法获得的热导率比通过稳态法获得的热导率高10-20％。热盘法测得的热扩散率平均等于稳态法测得的热扩散率，而前者的热扩散率变化很大。发现这些结果可以用杜福尔效应来解释，它是由传感器加热引起的质量流所引起的热流，以及在热盘法中现有的关于灵敏度系数的时间依赖性的发现。本研究提出了从热盘法计算木材热性能的两种方法，发现所获得的热性能与稳态方法所获得的热性能之间的误差因计算方法而异。