Influence of hot spots on the evolution of temperature and humidity in an underground granary

Hot spots within grain piles can lead to condensation in underground storage, significantly impacting long-term storage security. Investigating the effects of hot spots on the evolution of temperature and humidity within grain piles is crucial for developing measures to mitigate the threat to grain storage from condensation. This study utilized small-scale storage experiments to examine the impact of the number, location, and temperature of hot spots on the dynamic evolution of temperature and humidity within grain piles under 24 different cases. Initially, the distribution of temperature and humidity in wheat grain piles during static storage was analyzed to identify regions prone to condensation. Subsequently, artificial internal heat sources were placed in these regions to explore the patterns of temperature and humidity evolution during localized heating and natural ventilation phases with single and dual hot spots. The results indicated that during the single localized heating phase, heating at the midpoint of the grain loading line could potentially trigger secondary hot spots below the localized heating region and in the upper-middle layer of the grain pile. During the dual localized heating phase, simultaneous heating at the midpoint of the grain loading line and 0.05 m from the bottom of the right sidewall can potentially trigger secondary hot spots in the lower-middle layer of the grain pile.