Abstract Thermal conductivity controls heat transfer through materials, so accurate assessment of thermal conductivity is necessary when modeling the thermal behavior of a material. In this study, the thermal conductivities of a silty clay specimen, a sand specimen, and six types of mortar specimens with various mixing ratios of sand as an additive, were measured using box, dual-needle, and single-needle probes, with and without thermal grease, under saturated and oven-dried conditions. The results obtained with the needle probes were compared to those measured using the box probe, given the high accuracy of the box probe method. After applying thermal grease to single- and dual-needle probes, the thermal contact resistance decreased, resulting in increased thermal-conductivity values for soil and mortar specimens under saturated (wet) and oven-dried conditions. The thermal-conductivity values measured via the single-needle probe were as accurate as those measured by the box probe, whereas those measured using the dual-needle probe underestimated the material's thermal conductivity. Further research is required regarding thermal-conductivity measurements and the design of the tests and equipment used. The results of this study provide useful information for future studies of thermal-property measurements and probe development.

中文翻译：

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使用盒式、双针和单针探针法测量和比较多孔材料的热导率-案例研究

摘要 导热系数控制通过材料的热传递，因此在对材料的热行为建模时需要准确评估导热系数。在这项研究中，使用箱式、双针和单针探头测量粉质粘土试样、砂试样和六种砂浆试样的热导率，其中砂作为添加剂的混合比例不同，分别具有和不含导热油脂，在饱和和烘箱干燥条件下。考虑到盒式探针方法的高精度，将使用针式探针获得的结果与使用盒式探针测量的结果进行了比较。在单针和双针探针上涂抹导热硅脂后，接触热阻降低，导致土壤和砂浆试样在饱和（湿）和烘箱干燥条件下的导热系数值增加。通过单针探针测量的热导率值与盒式探针测量的热导率值一样准确，而使用双针探针测量的热导率值低估了材料的热导率。需要进一步研究热导率测量以及所用测试和设备的设计。这项研究的结果为未来热性能测量和探头开发的研究提供了有用的信息。需要进一步研究热导率测量以及所用测试和设备的设计。这项研究的结果为未来热性能测量和探头开发的研究提供了有用的信息。需要进一步研究热导率测量以及所用测试和设备的设计。这项研究的结果为未来热性能测量和探头开发的研究提供了有用的信息。