Abstract:

The time delay affects directly the measurement accuracy when the thermal conductivity(TC) is measured by the transient plane heat source technique. To investigate this effect degree, an improved model was proposed for the temperature rise with time delay compensation based on the ideal model for the mean temperature rise of the probe surface in the transient planar heat source technique. The TC of the standardized material Pyroceram 9606 at normal temperature and pressure was measured using the developed model and the data acquisition system of the Hot Disk analyser with 2 sensors of different radius. The results indicated that the relative error of TC measurement caused by time delay was sensitive to different choices of the test parameters. The shorter measuring time may result in larger error of TC measurement. The time delay compensation to the ideal model may enhance the TC measurement accuracy.

Key words: material examination and analysis, thermal conductivity, transient plane heat source technique, thermo-physical property, hot disk analyser