Application of a model to investigate the effective thermal conductivity of randomly packed fusion pebble beds

In our precious study, a prediction model, which calculates the effective thermal conductivity keff of mono-sized pebble beds, has been developed and validated. Based on this model, here the effects of these influencing factors such as pebble size, thermal radiation, contact area, filling gas, gas flow, gas pressure, etc. on the keff of randomly packed fusion pebble beds are studied and analyzed. The pebble beds investigated include Li4SiO4, Li2ZrO3, Li2TiO3, Li2O, Be and BeO pebble beds. In the current study, many important and meaningful conclusions are derived and some of them are similar to the existing research results. Particularly, some critters that under which conditions the effect of some influencing factors can be neglected or should be considered are also presented.