Improving Speed and Precision of Using Guarded Heat Flow Technique to Measure Thin Specimens
The components and calculation formulas of guarded heat flow method (ASTM E1530) are simple,and at the same time this instrument is widely used to measure thermal resistance and conductivity of various materials.In contrast to other methods such as guarded hot plate technique,it is able to measure thin specimens.However,since thermal resistance of thin materials is small,the heat transfer through plates and specimen is very fast,which requires thermocouples of the instrument response rapidly.Also,the dynamic response delay of thermocouples extends the time to reach steady state.In the issue of measurement accuracy,on the other hand,the thermal contact resistance cannot be neglected and sometimes can even be many times larger than specimensthermal resistance.This paper introduces a compensation algorithm and a different-layers calibration method to respectively focus on temperature measurement speed and thermal resistance elimination for the instrument.The experimental results have shown us that the precision and measurement speed of the instrument has been greatly improved by these methods.
guarded heat flow technique contact resistance compensation algorithm different-layers calibration
Qian-Chao Nie Yan-Ning Li Jian Liu Zhi Chen Dante J.Dorantes-Gonzalez
Sate Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, China
国际会议
天津
英文
192-196
2012-10-16（万方平台首次上网日期，不代表论文的发表时间）