A simulation study on the evolution of temperature field for bulk paddy rice in building warehouses in the Southwestern China

To investigate the temperature field variation patterns of rice stored in building warehouses in the Southwestern China, a case study was conducted on a bulk paddy rice building warehouse in Kunming. The COMSOL software was utilized to establish a temperature field model, and the data measured by temperature sensing cables in actual warehouse were compared to verify the reliability of numerical simulations. The temperature variation patterns of rice over a one-year static storage period were analyzed. The findings indicated that the temperature of the rice pile in building warehouses in the Southwestern China varied significantly within a 1.5 m range near the warehouse walls. Due to the respiration, the internal temperature variation within the rice pile was relatively small. There was a hysteresis effect between the internal temperature of the rice pile and the external environmental temperature, with a lag time of approximately 21 days during summer and autumn and about 15 days during spring and winter. During the transitions between spring and summer, as well as summer and autumn, the temperature variation of the rice pile fluctuated more significantly. The temperature trends of the rice piles on the standard floor and the top floor of the building warehouse were similar. However, due to direct sunlight exposure, the temperature difference between the top floor and standard floor was relatively large. The simulation results were consistent with the experimental results. The research methods and findings can provide technical support for the promotion of building warehouses in the Southwestern China.