提高低导热材料表面温度均匀性方法的研究

Research of Improving Surface Temperature Uniformity of Low Thermal Conductance Materials

比较了不同低导热材料的高温热导率测试装置特点,确定了在整体加热方式下试样表面温度均匀性差是限制测试准确度提高的一个原因,提出采用分区加热的方法改善试样表面温度均匀性。选取三种不同热导率范围的材料作为被测试样,分别做了试样整体加热和分区加热的模拟计算。结果表明,整体加热方式只能在试样表面中心有限区域形成均温区,而分区加热方式能显著改善试样表面温度均匀性。

The characteristics of thermal conductivity measurement apparatus for high temperature with different low thermal conductance were compared, and one of the reasons leading to low measurement accuracy was concluded, that is mainly caused by the poor temperature uniformity with whole heat- ing method. According to these analyses, the partition heating method was proposed for improving tem- perature uniformity of the specimen surface. Three materials with different thermal conductivity were used to experiment and simulation calculation through the whole heating and district heating method respective- ly. The experiment results show that a limited even surface temperature area can be formed on the center of the specimen with the whole heating method, and the entire surface temperature can be reached to a better uniformed state with the partition heating method.