Abstract
The effect of aeration on the thermal stability of self-heating powder beds is mathematically discussed. Judging from the steady thermal characteristics of powder beds, aeration greatly improves the thermal stability. However, a consideration on the dynamic characteristics reveals that aeration without careful attention to the temperature distribution in the powder bed can make the thermal stability into a very critical situation.
To avoid the possible risk of a thermal catastrophe, the restorable limit of the temperature distribution for a given aeration condition is proposed, below which the thermal stability is ensured. Aeration should be controlled so that the temperature at any position in the powder bed is always below the restorable distribution.
