Investigation on heat transfer between furnace atmosphere and hollow glass microspheres

To explore heat transfer process between the hollow glass microspheres and furnace atmosphere in fabricating hollow glass microspheres by the sol-gel technology, the effect of component percentage, temperature and total pressure of Ar/He gas mixture on the overall thermal resistance between microsphere and furnace atmosphere was studied. The influence of the diameter and the wall thickness of a microsphere on the overall thermal resistance was also investigated. The results show that, in the range of component percentage, temperature and pressure of Ar/He gas mixture commonly used in fabricating hollow glass microspheres by the sol-gel technology, an increase in the volume fraction of helium in the furnace atmosphere can significantly reduce the overall thermal resistance, but increasing t