3.2 Experimental Facility and Methodology
135
Fig. 3.8 a Statistical uncertainty of measured temperatures of α; b Effective thermal diffusivity
with error bar; c Effective thermal conductivity with error bar
Therefore, combining the above uncertainties, the standard uncertainty of λ is presented in Fig. (3.8c).
3.2.4 Short Summary
This section presents an overview of the full-radius-scale facility and experimental
process for measurements of effective thermal diffusivity and conductivity of pebble
bed under vacuum condition and temperature of pebble bed up to about 1,200
◦ C. The
temperature distribution reveals that this facility is exact enough to ensure symmetry
and stability and produce the desired temperature data. Also, the improved method
and the relationship between effective thermal diffusivity and conductivity are studied
in this section.
This section focuses on presenting the data processing method for effective thermal diffusivity and conductivity of a pebble bed. The availability, robustness, and
accuracy of this algorithm have been studied in the above sections. In terms of
this facility configuration, an inverse method is described and considered mainly