The transient plane source (TPS) technique, also referred as the Hot Disk method, has been widely used due to its ability to measure the thermal properties of an extensive range of materials (solids, liquids, and powder). Recently, it has been recognized that typical Hot Disk sensors can influence TPS results of thermally insulating materials and lead to an overestimation of thermal conductivity. Although improvements have been proposed, they have not yet been implemented in the commercial TPS, leaving researchers with non-standardized modifications or options provided by a commercial Hot Disk apparatus. An empirical study of thermally insulating materials such as extruded polystyrene (XPS) and aerogel blanket is conducted in order to address the factors that affect the reliability of thermal conductivity k obtained using the commercial TPS apparatus. Sensor size, input power, duration of the measurements, applied pressure, and, in the case of anisotropic materials, heat capacity are investigated, and the results are compared with those using a Heat Flow Meter apparatus. The effect of sensor size on the k value is ascribed to heat loss through connecting leads and is more pronounced in smaller sensors and in materials with lower k values. In the case of XPS and aerogel, the effect becomes minimal for sensors with a radius r ≥ 6.4 mm. The low input power yields a high scattering of the results and should be avoided. Applied contact pressure and the tested region of the specimen play an important role in experiments with low-density fibrous materials due to the large percentage of heat being transferred by radiation and the heterogeneous nature of the samples, respectively. Additionally, the sensitivity of anisotropic measurements to the value of the material’s volumetric heat capacity (ρC_p) is shown, emphasizing the need for the precise determination.

瞬态平面源（TPS）技术，也称为热盘方法，由于其能够测量多种材料（固体，液体和粉末）的热性能而被广泛使用。最近，已经认识到典型的热盘传感器会影响热绝缘材料的TPS结果，并​​导致对导热率的高估。尽管已经提出了改进措施，但是它们尚未在商用TPS中实施，这给研究人员留下了由商用Hot Disk设备提供的非标准化修改或选项。为了研究影响导热系数k的因素，进行了热绝缘材料（如挤塑聚苯乙烯（XPS）和气凝胶毯）的实证研究。使用商业TPS设备获得。研究传感器尺寸，输入功率，测量持续时间，施加的压力，以及在使用各向异性材料的情况下的热容，并将结果与​​使用热流量计的设备进行比较。传感器尺寸对k值的影响归因于连接引线的热损失，在较小的传感器和k值较低的材料中尤为明显。对于XPS和气凝胶，半径为r的传感器的影响最小 ≥6.4毫米。低输入功率会导致结果的高度分散，应避免使用。施加的接触压力和样品的测试区域在低密度纤维材料的实验中起着重要作用，因为分别有很大比例的热量通过辐射传递和样品的异质性。此外，各向异性测量材料的体积热容量（的值的灵敏度ρC _p）所示，强调了精确测定的需要。