Hot disk建模及模型精度分析

为了对瞬态平面热源技术进行准确的评估,在简化Hot disk探头结构的基础上,基于瞬态点热源格林函数法给出了Hot disk瞬态平面热源表面平均温度的理想模型推导过程;基于此理想模型并应用Hotdisk数据采集系统,针对Pyroceram 9606标准材料在常温常压测量条件下的热导率进行了计算.结果显示,计算值与Hot disk测量值的相对误差为6.17%,实际测量探头热容的存在、测量时间的延迟以及四线电阻的散热影响等因素是造成热导率测量精度下降的主要原因.

Modeling and accuracy analysis of Hot disk thermal constants analyzer

The aim of the research presented in this paper is to enhance our understanding of the Hot disk thermal constants analyzer and to have an accurate evaluation of Hot disk thermal constants analyzer, the average temperature increase in the sensor surface was deduced by using Green＇s function method. Based on the simplified structure of the disk probe and the standardized material Pyroceram 9606, with a thermal conductivity of 4.05 W/（mK） at room temperature and under normal pressure was investigated and analyzed by using the data acquisition system of the Hot disk thermal constants analyzer and a new developed model. The calculation result shows that the model precision has a relative error of 6. 17% estimated for thermal conductivity compared with the measurement result of the Hot disk, and the effects of the heat capacity of the Hot disk probe, the time delay of the data acquisition system and the elimination of heat from the four wire resistance in actual measurement are the main influencing factors of accuracy decrease.