CFD modelling and simulation for assessing temperature distribution inside flour mills during heat treatments for insect pest control

The heat treatment of the indoor environment of flour mills is an alternative to chemical fumigation for controlling insect pests. This method requires the increase of air temperatures between 45°C and 55°C, which should be maintained for a time interval of 36-48 hours to eliminate all the insect vital stages. However, some building components of the mill, such as floors, walls, and ceilings, can provide a refuge for insects from the heat, because their surface temperatures usually do not reach levels that are lethal to insects. Therefore, the objective of this research was to assess temperature distribution inside a flour mill during a heat treatment for insect pest control by computational fluid dynamics (CFD) modelling and simulation. The model was validated by means of experimental data acquired during a heat treatment carried out in a flour mill located in Sicily (Italy), representative of building materials and techniques used in the milling industry of South Italy.